Advanced carbon materials: electrochemical aspects

Resume : Graphene is a single-atom-thick sheet of hexagonally arranged, sp2-bonded carbon atoms that is not an integral part of a carbon material but is freely suspended or adhered on a foreign substrate, and has excellent properties, such as high mechanical strength and modulus, high thermal and electrical conductivities, very stable thermal and chemical stabilities, and unique electronic properties. Graphene films and membranes are expected to be used in various applications. Therefore, synthesis of graphene films and membranes in large area at reasonable cost is very important. Basically, graphene films and membranes can be synthesized by CVD and assembly from chemically exfoliated graphene sheets. We developed an ambient pressure CVD to synthesize large and small size single crystal graphene grains, and their continuous films [1,2,3,4]. Moreover, we invented an electrochemical bubbling method to efficiently transfer these grains and films [2]. Large area and continuous graphene transparent conductive films are produced by an integrated R2R process of CVD and bubbling transfer. Very recently, we have developed a green electrochemical water oxidation exfoliation process of graphite to produce high-quality graphene oxide in large quantity and high yield [5], and invented a continuous centrifugal casting process to rapidly produce high-quality graphene membranes in large area and tunable thickness from chemically exfoliated graphene sheets [6]. These graphene films and membranes may have wide applications in many fields, from electronics to optoelectronics, from sensors to wearable devices, and from separation to water treatment [7,8]. However, great efforts are highly needed for the research, development, commercialization and market explorations of graphene films and membranes. References [1] L. B. Gao, et al. Applied Physice Letters, 97, 183109 (2010). [2] L. B. Gao, et al, Nature Communications, 3, 699 (2012). [3] T. Ma, et al, PNAS, 110, 20386 (2013). [4] T. Ma, et al, Nature Communications, 8, 14486 (2017). [5] S. F. Pei, et al, Nature Communications, 9, 145 (2018). [6] J. Zhong, et al, Nature Communications, 9, 3484 (2018). [7] Z. K. Zhang, et al, Nature Communications, 8, 14560 (2017). [8] K. H. Thebo, et al, Nature Communications, 9, 1486 (2018).

Resume : In the past decade, lot of attention has been put on electrochemical double layer capacitors (EDLCs), also known as supercapacitors, for high power delivery or energy harvesting applications. The charge storage mechanism in supercapacitor electrodes relies on electrostatic attraction between the electrolyte ions and the charges at the electrode surface, leading to a charge separation at the electrolyte/electrode interface. During this presentation, we will show how the careful design of nanostructured carbons can help in preparing high energy density carbons for supercapacitor applications. The combination of several techniques like Electrochemical Quartz Crystal Microbalance (EQCM, in-situ NMR spectroscopy, and simulations has then been used for studying the ion confinement effect in carbon nanopores. These results helped in developing our basic understanding of the ions/carbon interactions in confined pores. From a practical point of view, they open new paths for designing high-energy density supercapacitors.

Resume : In this talk, I will summarize the recent research on synthesis and characterization of two-dimensional nanomaterials in my group, which include graphene-based composites, transition metal dichalcogenide (TMD)-based composites, single- or few-layer metal dichalcogenide nanosheets and hybrid nanomaterials, the large-amount, uniform, ultrathin metal sulfide and selenide nanocrystals, and other 2D nanomaterials, nanodots prepared from 2D nanomaterials, etc. Then I will demonstrate the applications of these novel 2D nanomaterials in water splitting, hydrogen evolution reaction, Li-ion batteries, supercapacitors, etc.

Resume : A plasma is a partially ionized gas, which is one of the four fundamental states of matter. The rich energetic species in plasmas enable them to be employed as a powerful tool for material synthesis, ranging from thin films to nanomaterials. The materials prepared with the plasma-enhanced techniques show some distinctive features, e.g., novel structure, improved efficiency, and defect control. Plasma technology may also facilitate reactions which are difficult for normal thermal approaches and reduce the growth temperatures. In this talk, the applications of microwave plasmas in the synthesis and modification of several nanomaterials such as diamond nanostructures, 3D vertical graphene arrays, and heterocrystalline and bicrystal ZnS nanowires, and their related properties, will first be introduced. Then some recent advances in the use of plasma technology in preparing nanomaterials for electrochemical energy conversion and storage applications will be discussed, e.g., a self-supported cathode comprising nickel nitride nanostructures enriched with nitrogen vacancies for hydrogen evolution reaction; hybrid porous nanosheet networks composed of cobalt-based nitride and oxide for hydrogen evolution reaction; and Cu-CuO-Ni hybrid structures as current collectors toward stable lithium metal anode.

Resume : Energy storage materials and devices are important and essential for the sustainable development, and the research and development in this field are very active and ever-increasing. Energy Storage Materials (EnSM) is an international multidisciplinary journal for communicating scientific and technological advances in the field of materials and their devices for advanced energy storage and relevant energy conversion (such as in metal-O2 battery). As an elite member of the family of journals ‘Materials Today’, it publishes comprehensive research articles including full papers and short communications, as well as topical feature articles/reviews by leading experts in the field. In this talk, we will briefly introduce the Editorial team, Aims and Scopes, publication policies, publication facts (acceptance ratio, citations and impact metrics, and editorial speed), and main topics of research reflected in the journal. Finally and more importantly we will try to identify future research and development trends of energy storage materials and devices based on the data collected from EnSM.

Resume : In the field of nanomedicine, nanoparticles with various functions are required for in vivo applications such as biomedical imaging and drug delivery. Therefore, chemical functionalization of nanoparticles has been extensively investigated. Herein, nanodiamond (ND) coated with polyglycerol (PG) and its derivatives is reported to impart good dispersibility in a physiological environment, a stealth nature to avoid nonspecific uptake, a targeting property to be taken up by a specific cell, and an acid-responsive drug release property to kill cancer cells [1-5]. ND is first grafted with PG and the resulting ND-PG has a high dispersibility in physiological media. Since a large number of hydroxyl groups in PG provide scaffolds for further surface functionalization, the targeting RGD peptide and Pt-based drug are immobilized to give ND-PG-RGD, ND-PG-Pt and ND-PG-RGD-Pt. The ND with intrinsic fluorescence is also functionalized by PG and RGD to confirm cellular uptake and intracellular localization fluorescently. The results of the cell experiments indicate that PG coating shielded fND from the uptake by HeLa and U87MG cells. In contrast, fND-PG-RGD is taken up by U87MG, not HeLa cells, exhibiting high targeting efficacy. When ND-PG-RGD-Pt is applied, U87MG is selectively killed against HeLa. The multi-functional ND is a promising prodrug in targeting chemotherapy. References 1. T.-F. Li??, K. Li, Q. Zhang, C. Wang, Y. Yue, Z. Chen??, S.-J. Yuan, X. Liu, Y. Wen??, M. Han?, N. Komatsu, Y.-H. Xu?, L. Zhao,* X. Chen,* "Dendritic cell-mediated delivery of doxorubicin-polyglycerol-nanodiamond composites elicits enhanced anti-cancer immune response in glioblastoma" Biomaterials, 181, 35-52 (2018). 2. L. Zhao, H. Yang, T. Amano, H. Qin, L. Zheng, A. Takahashi, S. Zhao, I. Tooyama, T. Murakami, N. Komatsu,* "Efficient Delivery of Chlorin e6 into Ovarian Cancer Cell with Octalysine Conjugated Superparamagnetic Iron Oxide Nanoparticle for Effective Photodynamic Therapy" J. Mater. Chem. B, 4(47), 7741-7748 (2016). 3. L. Zhao, Y.-H. Xu, H. Qin, S. Abe, T. Akasaka, T. Chano, F. Watari, T. Kimura, N. Komatsu,* and X. Chen* "Platinum on Nanodiamond: A Promising Prodrug Conjugated with Stealth Polyglycerol, Targeting Peptide, and Acid-Responsive Antitumor Drug" Adv. Funct. Mater., 24 (34), 5348-5357 (2014) [highlighted at the inside front cover]. 4. L. Zhao, Y.-H. Xu, T. Akasaka, S. Abe, N. Komatsu, F. Watari, and X. Chen* "Polyglycerol-coated Nanodiamond as a macrophage-evading platform for selective drug delivery in cancer cells" Biomaterials, 35 (20), 5393-5406 (2014). 5. L. Zhao, T. Takimoto, M. Ito, N. Kitagawa, T. Kimura, and N. Komatsu,* "Chromatographic Separation of Highly Soluble Diamond Nanoparticles Prepared by Polyglycerol Grafting" Angew. Chem. Int. Ed., 50 (6), 1388-1392 (2011) [highlighted at back cover].

Resume : Nitrogen-vacancy (NV) in diamond serves as a promising sensor for many applications ranging from condense matter physics to biomedicine. In the present work, we developed a new scheme to investigate the mechanical properties of soft materials using diamond nanoparticles as the quantum sensors. We showed proof-of-the-concept demonstration using polydimethylsiloxane (PDMS) film and gelatin microparticle. The excellent sensitivity and spatial resolution associated with such a technique enable the disclosure of heterostructured nature of the former, and effect of surface tension in the latter. This work has been carried out in collaboration with Renbao Liu, Kangwei Xia, Wenghang Leong, Manhin Kwok, Chufeng Liu, and Zhiyuan Yang. We acknowledge funding from CRF of RGC (Project No. C4006-17G); and CUHK Group Research Scheme (Project No. 31110126).

Resume : Over last few decades, designing efficient electrode materials is being of immense interest to fulfil the need of miniaturized portable energy storage (ES) equipments. In recent years, for ES applications especially electrical double layer capacitors (EDLC), sp2 carbon materials are used frequently due to their large specific capacitance (Cs). However, small overpotential in oxygen hydrogen evolution reaction limits their usage in aqueous solution (AS), whereas boron doped diamond (BDD) shows unmatched potential window in AS making them promising for electrochemical supercapacitor applications. In present work, the combined performance of both sp2 and sp3 carbon as SC has been demonstrated by preparing conductive BDD-multi-layered graphene (MLG) core-shell nanowalls (NWs) using microwave plasma enhanced chemical vapour deposition system. A promising Cs value of 208 μF/cm2 at a current density of 2.55 μA/cm2 has been recorded for the MLG-BDD electrode in 1M Na2SO4 AS with a loss of only 12.5% in Cs after 2000 charge discharge cycles. This high EDLC value with long lifetime is due to collective effect of the curled interconnected NW like morphology which facilitates electron conduction and microstructural arrangement of core-shell granular structure i.e. a BDD core encased by a MLG shell, revealed by the high-resolution transmission electron microscopy. These results indicate that fabrication of this hybrid material could be suitable for future ES devices.

Resume : Formation of hydroxyl, carbonyl and other termination bonds on the surface of boron-doped diamond (BDD) is an important process affecting hydrophobicity, electrolytic potential window, surface conductivity and reaction kinetics, also leading to electroanalytical selectivity of these electrodes. It is said that the transformation of hydrogenated to oxygenated BDD termination type is characterized by multistage mechanism, affected by conditions and length of the exposure to oxidizing agent, boron dopant concentration, sp2-C contamination, crystallographic texture and others. Studies utilizing novel multifrequency Nanoscale Impedance Microscopy technique revealed a large variation in local surface resistance of BDD electrodes previously subjected to different anodic polarization treatments. The observed behaviour of this characteristic feature was varying for individual crystallites, depending on their orientation. Furthermore, we have investigated various types of oxidation procedures proving significant differences in local homogeneity of surface oxidation but also the types of oxidized termination functional groups. We demonstrate that heterogeneous termination kinetics and resultant sub-microscopic distribution of electric properties noticeably affects the electrochemical response. The discussed feature holds partial responsibility for the unsatisfactory reproducibility in reported electrochemical studies. Acknowledgement: The authors gratefully acknowledge financial support from the National Science Centre Grant Sonata No. 2015/17/ST5/02571 and National Centre for Science and Development Grant Techmatstrateg No. 347324.

Resume : As an advanced carbon material, boron-doped diamond (BDD) based electrochemical advanced oxidation processes have attracted much attention in the field of environmet. However, few systematic studies about the radical mechanism at BDD anode has been published. In situ electron paramagnetic resonance (EPR) spectrometry was carried out with a customized Allendoerfer-type electrochemical cell with a saturated calomel reference electrode placed outside the space-limited electrolysis cavity and connected to the latter with a Luggin capillary. Confirmed by in situ EPR signal of DMPO•-OSO3H (fitted as g=2.0066, AN=1.375 mT, AHβ=1.015 mT, AHγ1=0.140 mT, and AHγ2=0.074 mT), sulfate radical anion was directly electro-generated from sulfate by direct electron transfer, then, surplus sulfate radical anion dimerized to form persulfate and accumulated in electrolyte. The formed persulfate was quantified by back titrimetry and characterized by wide-angle X-ray diffraction patterns after vacuum crystallization. However, no persulfate accumulated in alkaline solutions owing to sulfate radical anion rapidly transform to •OH, which has lower oxidation potential. Therefore, persulfate immediately disintegrated even if it formed. When the voltage was beyond the overpotential of water oxidation, the •OH electro-generated and cooperated with sulfate radical anion. In the power-off phase, the accumulated persulfate could be reactivated to sulfate radical anion via current thermal effect or quinones degradation intermediates. Thereby achieving sustainable degradation in the power-off phase. Dimethyl phthalate (DMP), a typical endocrine disruptor, was selected as a model contaminant to gain more insight. Surprisingly, 98.6% DMP (initial concentration of 1 mg L-1) was removed, given by an intermittent power supply strategy with periodic 15 min power-on phase at a duty ratio of 2:3, and more than 22% of electrical energy consumption (1.2 kWh m-3) was economized compared with continuous power supply. The feasible persulfate thermal reactivation mechanism was elucidated through in situ variable temperature EPR spectroscopy. Further studies investigated whether the •OH initiated intermediates may also act as persulfate activators once the electrochemical oxidation begins, and indicated a novel collaboration of •OH and sulfate radical anion. This work clarified the electro-generation, transformation and synergy of hydroxyl radicals and sulfate radical anions under different conditions and the continuous oxidation ability in the power-off phase, and these results provide a theoretical basis for efficient water treatmentwith BDD anodes.

Resume : Humidity sensing is of significant interest to monitor and control the moisture in humidity sensitive environments such as clean rooms, agricultural and industrial production, food storage units and glove boxes. In this work, a novel 3D printable composite consisting of boron doped diamond (BDD) (60 wt %) and LiCl (2 wt %) in acrylonitrile butadiene styrene (ABS) has been developed. The newly developed composite provided electrical conducting properties through conductive BDD powder and humidity sensing properties from the LiCl. The filler distribution and surface properties of the material was characterised using scanning electron microscopy (SEM) and electrical conductivity was determined by measuring current vs voltage plot. In comparison to traditional sensors consisting of multiple components e.g. humidity sensing film, coating support, and interdigital electrodes, the novel composite material allowed simple and quick (approx. 2 min) fabrication of single piece humidity sensor, BDD dispersed in the polymer matrix functioned as the electrodes, using low cost fused deposition modelling 3D printer. The humidity sensing properties of the sensor were investigated by measuring the change in resistance of the sensor over varying relative humidity levels. A significant change in the resistance of 3D printed humidity sensor, up to 2 orders of magnitude, was observed by varying the % relative humidity between 11 and 97 %. The response and recovery time (120±30 and 200±30 s respectively) obtained using 3D printed humidity sensor are in reasonable agreement with the reported values. The stability of the detector over long period was also investigated with relative standard deviation of less than 10 % for a period of 14 days.

Resume : Since heavy metal ions (HMIs) are considered to be one of the serious source to pollute the biosphere throughout the world, the challenge of heavy metal detection for environmental, industrial and medical purposes has led to the development of many analytical techniques. Sensitive and selective determination of toxic HMIs with a cost-effective and convenient procedure is of paramount importance. Anodic stripping voltammetry (ASV) is a very sensitive electrochemical method, capable of simultaneous detection of these HMIs with low detection limit. The major aim of our research is to design ecologically friendly electrodes for electrochemical (EC) detection of these HMIs. Doped (B-, N- and P-) diamond materials appear as an alternative over other carbon based materials due to their unique physical, chemical and EC properties. Here, we report the applicability of nitrogen-doped diamond nanorods (N-DNRs) as an EC sensor towards the detection of Pb2+ and Cd2+ ions. The limit of detection values are found to be 50 nano molar using ASV measurements of both these ions respectively. In addition, scanning transmission electron microscopy studies reveal that the formation of graphitic phases at the grain boundaries of N-DNRs is responsible for the enhanced electron transport kinetics and the EC sensing performance. The EC results suggest that environment friendly N-DNR is an excellent electrode material for the simultaneous detection of numerous HMIs.

Resume : Wearable energy storage devices are indispensable corner stones for future wearable electronics. Current energy storage technologies are based on materials and devices that are rigid, bulky, and heavy, making them difficult to wear. On the other hand, fibers are flexible and lightweight materials that can be assembled into different textiles and have been worn by human beings thousands of years. Different from conventional two-dimensional thin films and foils, the three-dimensional fibre and textile structures not only provide superior wearing ability, but also much larger surface areas. This talk will introduce how our research group makes use of the attributes of fibres for high-performance wearable energy storage devices. We will demonstrate the strategies and discuss the perspectives to modify fibers and textiles for making wearable capacitors and batteries with excellent mechanical durability, electrochemical stability, and high energy/power density.

Resume : Conductive porous carbons, which possess high specific surface area, have long dominated the field of electrical double layer capacitor. Semiconductive carbon is also one important player in carbon field, but very limited research focuses on its application in supercapacitor and corresponding mechanisms. In this talk, I will briefly introduce the background of semiconductive carbons, and show a few very recent progresses of our group about new methods towards semiconductive carbons, the unique optoelectronic properties of such semiconductive carbons, how to constructive semiconductive carbon based heterostructures for supercapacitors and understanding the mechanism for such new heterostructures by in situ synchrotron radiation. The energy conversion properties of as-developed semiconductive carbons will be also briefly introduced. Reference [1]. C. Lu, J. Yang, S. Wei, S. Bi, Y. Xia, M. Chen, Y. Hou,* M. Qiu,* C. Yuan, Y. Su, F. Zhang, H. Liang,* X. Zhuang*, Atomic Ni Anchored Covalent Triazine Framework as High Efficient Electrocatalyst for Carbon Dioxide Conversion, Adv. Funct. Mater. 2019, in press. [2]. J. Zhu, C. Yang, C. Lu, F. Zhang,* Z. Yuan,* X. Zhuang*, Two-Dimensional Porous Polymers: From Sandwich-Like Structure to Layered Skeleton, Acc. Chem. Res. 2018, 51, 3191-3202. [3]. F. Wang, H. Yang, J. Zhang, P. Zhang, G. Wang, X. Zhuang,* G. Cuniberti, X. Feng*, A Dual-Stimuli-Responsive Sodium Bromine Battery with Ultra-High Energy Density, Adv. Mater. 2018, 30, 1800028 [4]. P. Zhang, J. Wang, W. Sheng, F. Wang, J. Zhang, F. Zhu, X. Zhuang,* R. Jordan, O. Schmidt, X. Feng*, Thermoswitchable on-chip microsupercapacitors: One potential self-protection solution for electronic devices, Energy Environ. Sci. 2018, 11, 1717-1722. [5]. P. Zhang, F. Wang, M. Yu, X. Zhuang,* X. Feng*, Two-dimensional materials for miniaturized energy storage devices: from individual devices to smart integrated systems, Chem. Soc. Rev. 2018, 47, 7426-7451. [6]. C. Yang, K. Schellhammer, F. Ortmann, S. Sun, R. Dong, M. Karakus, Z. Mics, M. Löffler, F. Zhang, X. Zhuang,* E. Cánovas,* G. Cuniberti, M. Bonn, X. Feng*, Coordination Polymer Framework Based On-Chip Micro-supercapacitors with AC Line-Filting Performance, Angew. Chem. Int. Ed. 2017, 56, 3920-3924. [7]. P. Zhang, F. Zhu, F. Wang, J. Wang, R. Dong, X. Zhuang,* O. Schmidt, X. Feng*, Stimulus-Responsive Micro-Supercapacitors with Ultrahigh Energy Density and Reversible Electrochromic Window, Adv. Mater. 2017, 29, 1604491. [8]. T. Jin, C. Tian, X. Zhu,* C. Lu, S. Yang, X. Zhuang,* H. Liu,* S. Dai*, In Situ Coupling Strategy for the Preparation of FeCo Alloys and Co4N Hybrid for Highly Efficient Oxygen Evolution, Adv. Mater. 2017, 29, 1704091.

Resume : As a promising substituent for traditional lithium-ion batteries, lithium-sulfur (Li-S) batteries have attracted tremendous scientific attention owing to their superior energy density and low cost. However, the detrimental shuttling behavior due to the mobility of soluble polysulfide intermediates (LiPSs) and sluggish redox kinetics of active materials caused by sophisticated multielectron redox reactions significantly degrades the capacity, rate capability and cycling life of Li-S batteries. Previous works introducing compounds with only absorption ability towards LiPSs or only catalytic activity towards LiPSs conversion indicated insufficient performance improvement in Li-S batteries at high current density especially with high sulfur loading. Introducing electrocatalytically active components with collaborative interface properties offering both high LiPSs adsorption and conversion ability is an effective strategy to tackle the bottlenecks. However, precise design of catalytic component with strong adsorption towards LiPSs, high electrical conductivity and sufficient reactive sites for controllable precipitation of Li2S simultaneously are still challenging. Herein, we present a novel catalyst design to kinetically propel polysulfide-involving redox reactions with high efficiency by in-situ crafting a unique TiO2-MXene heterostructure. The uniformly distributed TiO2 nanocrystals on MXene sheets act as capturing centers to immobilize LiPSs, while the hetero-interface ensures rapid diffusion of anchored LiPSs from TiO2 to highly conductive MXene for fast conversion. The oxygen terminated MXene surface, oxidized during a hydrothermal treatment, is endowed with high catalytic activity towards LiPSs redox reaction. As a result, the Li-S batteries with an interlayer composed of TiO2-MXene heterostructures and graphenes deliver high sulfur utilization and stable cycling performance. Furthermore, to conqure the sluggish activation process and high charging over-potential of Li2S, we further design a bi-directional electrocatalyst by nitridation of binary transition-metal oxides (TMOs) in NH3 with optimized conditions, in the process of which a heterostructure consisting of metal nanoparticles and metal nitrides grown together was synthesized. On one hand, the homogeneously distributed and small sized metal nanoparticles can provide sufficient active sites for the rapid conversion of LiPSs to Li2S. On the other hand, the metal nitrides with good lithiophilicity and high electrical conductivity are essential for reducing the charging over-potential of formed Li2S, thus catalyzing its fast conversion to LiPSs and further to S. More importantly, the structure of metal nanoparticles incorporated in metal nitrides can effectively facilitate the transfer of active materials between them due to the reduced transfer barrier, further promoting the entire conversion efficiency. When used as a functional additive in S cathode, this unique heterostructure can bring about significant electrochemical performance improvement in term of rate capability and cycling stability, indicating its great potential for high-performance Li-S batteries. We believe that these two works open a new insight into the design of high-performance catalyst with manipulated chemical components, tailored surface chemistry and collaborative interface properties to regulate the kinetic behaviors of soluble LiPSs and Li2S and are also expected to be applied in other related energy storage and conversion systems, such as fuel cells and metal-air batteries.

Resume : Electrospray process is an inexpensive method for the production of particulate films for various applications. In particular, the electrospray of carbonaceous precursor sol (e.g., Resorcinol Formaldehyde) on the current collector, and subsequent curing and carbonization of the film in situ can be utilized for fabrication of supercapacitor electrodes. The presence of nitrogen in the carbonaceous precursor e.g., in the form of Melamine Formaldehyde, or as part of catalyst e.g., ethylenediamine can introduce pseudocapacitance that is of advantage, in the electrochemical cell. This presentation describes a process of preparing binder-free in situ grown nitrogen-enriched carbon nanoparticulate film electrodes by electrospray of polymeric precursor sol. The electrospray process utilizes a high voltage electric field at the tip of the needle to split the precursor sol into fine droplets by Coulombic fission, prior to the deposition on the current collector. The continuous deposition of droplets followed by in situ curing, drying, and carbonization results in a carbon film with interconnected pore network on the current collector. Carbon paper is used here as a current collector to ensure better adhesion with the deposited film during the post-deposition processing of the composite. The electrospray deposited layer of sol underwent gelation through addition and polycondensation reactions to form cross-link network. This gel layer was subjected to lyophilization, and carbonization to yield porous nitrogen-enriched carbon film. The lyophilization process enabled solvent removal without causing vapor-liquid interface induced stresses, thus retaining the pore space in the final film. The hierarchical pore structure was analyzed through nitrogen adsorption-desorption experiment on bulk carbons, produced by the identical protocol. The electrodes were studied under FE-SEM to identify the pores at different magnifications. Electrochemical measurements were performed to evaluate the capacitance of the film electrode, and extent of pseudocapacitance after charge-discharge cycles.

Resume : In this study, we have designed an oriented nanoporous carbon (ONPC) structure by directly growing metal-organic framework (ZIF-67) onto the surface of layered double hydroxide (CoAl-LDH) via solvent synthesis method, following by a subsequent pyrolysis process. The formation mechanism of LDH@ZIF is involved partial dissolution/coordinative interaction of LDH with ZIF-67 in a solution of 2-methylimidazole. TEM images and FE-SEM images of ONPC structure showed a honeycomb-like layered structure. Material characterizations were systematically obtained honeycomb-like layered structure by XPS, XRD, TGA, BET and FTIR. Note XRD showed the plane of LDH (003) at 2θ = 10.5° is matched with the plane of ZIF-67 (002) at 2θ = 10.4° in LDH@ZIF-67, indicative of that the MOF microstructure in-situ grew onto the surface of CoAl-LDH. The honeycomb ONPC exhibited a high specific capacitance (483 F．g-1 at 0.5 A．g-1) and excellent cycling stability (95.7 % after 5000 cycles) while evaluated as promising electrodes for battery-type supercapacitor. This MOF-driven strategy can be expanded to the preparation of other nanoporous carbon by ZIF stacking on LDH and open a window for potential application in high-performance supercapacitors.

Resume : As a rising star of carbon allotropes, graphynes (GYs) merely consist of spand sp2-hybridized carbon atoms, which endow them a large conjugated network and expanded 2D porous structure. With unique topological structure, GYs display unusual semiconducting properties, especially in the aspects of charge mobility and electron transport. Among the members of the GY family, only graphdiyne (GD) can be successfully synthesized in large quantities. The advanced properties of GD make it promising in various applications. Here, we report the recent progress in doping and composite of GD as well as their applications in photorelated and electrocatalytic applications. This new carbon allotrope, i.e., GD, has excellent intrinsic electrical, mechanical, and optical properties. When combined with metal nanoparticles, semiconductors or doped with other elements, it can greatly enhance the charge separation and transportation during the photorelated or electrocatalytic conversion processes, bridging the gaps between semiconductors or metal nanoparticles by providing good electrical contact and low interfacial resistance. Their excellent performance in photo- or electrochemical conversion areas suggests they are a cost-effective and superior alternative to the prevalent carbon materials. Reference: 1. Adv. Sci., 2018, 1800959. 2. Nature Chemistry, 2018, 10, 924 3. ACS Nano, 2013, 7, 1504-1512. 4. Small 2012, 8(2): 265-271. 5. Adv. Energy Mater. 2015, 5: 1500296.

Resume : Supercapacitors endowed with the features of high charge-discharge rate, high power density and high cycle stability, are promising for the most developed energy storage devices nowadays. Metal–organic framework (MOF), due to its high specific surface area and tunable porosity, is a good candidate material for electric double-layer energy storage in supercapacitors. However, the poor electrical conductivity of MOFs limited their applications. In general, strategies including carbonization and the induction of conductive additives are commonly utilized to enhance their conductivity. Furthermore, MOFs tended to aggregate during the fabrication process, resulting in a poor efficiency of diffusion for electrolyte and the disconnection between electrolyte and electrode.In this study, silk fibroin (SF), because of its excellent mechanical properties, easy to chelated with metal ions, and high conductivity/capacitance after carbonization, was suitably served as the template for the growth of MOFs crystalline. This as-prepared hierarchical SF hydrogel network effectively dispersed MOFs to boost the surface areas; moreover, it provided macroporosity/mesoporosity to promote diffusion and to facilitate the electrode/electrolyte interface affinity.An 5 times diluted pristine SF solution was mixed with cobalt nitrate to form a red metal ion-gelation colloidal solution,. Followed by freeze-drying, a 3D hierarchical Co-chelated SF aerogel is formed. Afterwards, in-situ growth of MOF crystallines was induced via a room temperature (RT) hydrothermal method. Finally, the MOF (ZIF-67) SF aerogel was carbonized into a 3D hierarchical porous carbon structure under 800℃. The SEM images showed the existence of ZIF-67 shaped with polygon geometries and the SF aerogel matrix with a 3D hierarchical network. X-ray diffraction (XRD) was used to confirm the crystal structure of MOF. For the BET analysis, the N2 absorption increased significantly at high pressure and a hysteresis loop was observed, indicating the introduction of enriched mesoporous and macroporous structure. Cyclic Voltammetry (CV) curve for ZIF-67 carbonized SF areogel performed a rectangular-like shape, showing a typical electric double layer storage mechanism. In addition, exhibited a high specific capacitance of 2452 mAh/g and remained 85% of its initial capacitance after 10000 cycles.In this study, the ZIF-67 carbonized SF aerogel with superior conductivity, versatile porosities, high capacity and applicable mechanical strength was successfully synthesized. The ZIF-67 carbonized SF aerogel shed the lights on the next generation of high performance supercapacitor.

Resume : Transition metals embedded nitrogen-doped carbon have spurred great potential in electrochemical energy storage. Here, we present a simple method to construct a cobalt nanoparticles embedded N-doped carbon matrix (Co@NC) exposed rhombic dodecahedron morphology. Uniform Zeolitic Imidazolate Framework-67 rhombic dodecahedrons are first manufactured as the precursor and thereafter readily converted into Co@NC rhombic dodecahedrons under the nitrogen atmosphere. Furthermore, as obtained material deposited onto the nickel form to use as an electrode for electrochemical supercapacitor, which shows a high specific capacitance along with long term cycling stability. Therefore, we believe that this work would be helpful and clear for the synthesis of transition metals and carbon composite structure for electrochemical energy storage.

Resume : We study the dissociative adsorption of methane at the surface of graphene. Free energy profiles, which include activation energies for different steps of the reaction, are computed from constrained ab initio molecular dynamics [1]. At 300 K, the reaction barriers are much lower than experimental bond dissociation energies of gaseous methane, strongly indicating that the graphene surface acts as a catalyst of methane decomposition. On the other hand, the barriers are still much higher than on the nickel surface. Methane dissociation therefore occurs at a higher rate on nickel than on graphene. This reaction is a prerequisite for graphene growth from a precursor gas. Thus, the growth of the first monolayer should be a fast and efficient process while subsequent layers grow at a diminished rate and in a more controllable manner. Defects may also influence reaction energetics. This is evident from our results, in which simple defects (Stone-Wales defect and nitrogen substitution) lead to different free energy landscapes at both dissociation and adsorption steps of the process. Our studies contribute to the presently actively developing field of non-metallic catalysts. [1] M. Wlaz?o and J. A. Majewski, J. Chem. Phys. 148, 094703 (2018) Acknowledgements: Support of NCN through the grant OPUS (UMO-2016/23/B/ST3/03567) is acknowledged.

Resume : Electrochemically driven green energy conversion (e.g. carbon dioxide reduction, oxygen reduction reaction, and water splitting, etc.) have been rising as an emergence research field due to the global warming and energy crisis. Development of efficiency catalysts to boost reaction is imperative and still an ongoing challenge. Herein, we present two facial in-situ strategies for fabricating porous carbon materials, which can be widely used in carbon dioxide reduction (CO2RR) and hydrogen evolution reaction (HER). Firstly, with the help of a convenient interfacial strategy, a new kind of Mo2C-embedded nitrogen-doped porous carbon nanosheets (Mo2C@2D-NPC) was successfully achieved. As HER electrocatalyst in alkaline solution, Mo2C@2D-NPC exhibited an extremely low onset potential of ~0 mV and a current density of 10 mA cm-2 at an overpotential of ~45 mV, outperforming the state-of-thr-art commercial Pt/C. Besides, we present a Ni porphyrin based covalent triazine framework (NiPor-CTF) with atomically dispersed NiN4 centers via ionothermal strategy as efficient electrocatalyst for CO2 reduction reaction. Typically, NiPor-CTF exhibits high selectivity toward CO2RR with a Faradaic efficiency of >90% over the range from -0.6 to -0.9 V for CO conversion and achieves a maximum faradaic efficiency of 97% at -0.9 V with a high current density of 52.9 mA cm-2, as well as good long-term stability.

Resume : Artificial photosynthesis refers to the conversion of water and CO2 into value-added chemicals powered by sunlight, and is the holy grail of a sustainable carbon cycle of chemicals. Since a big challenge facing this system is the conversion of stable CO2 into the desired chemicals, most studies have focused on the development of high-performing catalysts within well-refined and restricted test environments. However, such superior performances cannot guarantee their feasibilities in realistic conditions for future commercialization or practical application unless their durability issues are secured. Here, we report a one-step ahead approach to develop a more practical and advanced CO2 electroreduction catalyst with essential clues to overcome the obstacles from realistic conditions, based on the understanding of CO2 reduction deactivation phenomena. Our investigation firstly deals with the performance profile of an Ag electrode, selected as a standard catalyst for CO production, in real-life used tap water which is representative general purpose water. Screening and accompanying thorough analyses on various components in tap water ranging from alkali earth metals to transition/post-transition metals elucidated the types of impurities that can impede the catalytic activity by surface deposition, and consequentially cause the deactivation. Based on the findings involving Ag, a design strategy for a catalyst having excellent tolerance to the deactivation factors was suggested using a carbon-based material with heteroatom-doped active sites. A metal-free nitrogen-doped short carbon nanotube was prepared and showed stable performance in an unprecedented long-time of 120 hours in tap water media.

Resume : Atomically dispersed M-N-C catalysts with MNx moieties as active sites have emerged as a new frontier in electrocatalysis. In comparison with traditional heterogeneous catalysts comprising metallic particles with a broad size distribution, the single-metal-atom sites in model M-N-C catalysts possess well-defined structures with tunable coordination environments, leading to their superior activity, selectivity and maximum atom utilization efficiency. Thus, atomically dispersed M-N-C materials hold great potential as catalysts for clean energy storage and energy conversion reactions, including oxygen reduction reaction (ORR) and CO2 reduction reaction (CO2RR). Particularly, after decades of extensive efforts devoted to develop and understand Fe(Co)-N-C catalysts, substantial progress has been made in their catalytic activity toward ORR,1-3 bringing us closer to empowering precious metal-free cathodes in practical H2/air proton and/or anion exchange membrane fuel cells. Recently, M-N-C catalysts have been intensively investigated in CO2RR to lower the activation barrier needed to break the strong C=O bond in CO2, and suppress the HER side reaction, leading to reduced overpotential and enhanced selectivity.4 Significant progress has been achieved in synthetizing atomically dispersed M-N-C catalysts via high temperature pyrolysis, and stabilizing the obtained single-metal-atom sites against agglomeration. However, the exact structures of MNx moieties, especially under working conditions, are still unclear yet, impeding the rational advancements of their catalytic activity and/or stability. Operando x-ray absorption spectroscopy (XAS) is capable of probing the surface oxidation state and local atomic-structure transformation of active sites under electrochemical conditions.3,5,6 Herein, ex situ and operando XAS were utilized to unveil the structures of MNx active sites under CO2RR conditions in aqueous electrolyte. For some specific metals, drastic changes in oxidation state and structure of MNx sites (various 3d transition metals) with electrochemical potential have been observed, and the reversibility or not of those changes will be discussed, as a function of the nature of the metal. These results provide valuable insights on the structure-activity relationship of pyrolyzed M-N-C materials. Acknowledgement: The research leading to these results has received funding from the A-LEAF Project, which is funded by the European Union’s H2020 Programme under Grant Agreement No.732840 References 1. A. Zitolo et al. Nat. Mater. 2015, 14, 937. 2. H.T. Chung et al. Science 2017, 357, 479. 3. A. Zitolo et al. Nat. Comm. 2017, 8, 957. 4. W. Ju et al. Nat. Comm. 2017, 8, 944. 5. J. Li et al. Energy Environ. Sci. 2016, 9, 2418. 6. N. Leonard et al. Chem. Sci. 2018, 9, 5064.

Resume : Carbon dots exhibit outstanding physiochemical properties in aqueous dispersion, leading to various promising applications in photocatalysis and related fields. The electronic interaction between carbon dots and water molecules is, however, poorly understood. To shed light into this, we present the in-situ X-ray absorption spectroscopy characterization of carbon dots measured directly in aqueous dispersion. Three carbon dots dispersions with different core structures (amorphous vs. graphitic) and different compositions (with vs. without nitrogen doping) were investigated. By detecting the photocurrent generated by X-ray irradiation of the carbon dots dispersions at the carbon K-edge, the effect of the core structure of carbon dots on their charge transfer properties to the solvent is uncovered. In addition, by probing water molecules at the oxygen K-edge, the different hydrogen bond networks among three different carbon dots dispersions have been compared. The graphitization and the core nitrogen doping endow the carbon dots with facilitated electrons transfer and strong hydrogen bonding with surrounding water molecules, which may explain their enhanced photocatalytic performance. The deep mechanistic understanding based on the in-situ soft X-ray absorption spectroscopy will serve as a key guidance to improve the design of photocatalysts.

Resume : It is of utmost importance to investigate the multiple interactions among biological species in biology and medicine. However, the lack of analytical methods for the determination of multiple species at the same time and the same location is the bottleneck for understanding the corresponding physiological and pathological processes of biological species. Fluorescence sensing combined with molecular imaging provides a powerful methodology for studying cell biology in a noninvasive manner with high spatial and temporal resolution, and the mixed fluorescent probes or modifying different responsive molecules onto the same nanomaterial are powerful methods to achieve simultaneous detection and imaging of multiple substances. However, modifying different responsive molecules onto the same nanomaterial usually affected by the fluorescence resonance energy transfer (FRET) or cross-talk and the mixture of different probes generated different localizations, different concentration ratios, and altered metabolisms, making the scenario very complicated. Thus, real-time determination and simultaneous quantification of multitarget at the same localization remains challenging using a single probe to dissect their interplay in live cells, especially in subcellular structure. Herein, a single highly selective DNA nanoprobe was designed and created for the real-time imaging and simultaneous quantification of two kinds of biological species using Ca2 and pH; the molecules were selected as models because of their close relationship with cellular functions and diseases. A Ca2 fluorescent probe was synthesized and assembled onto a DNA nanostructure together with pH-responsive, inner-reference, and mitochondria-targeted molecules. This nanoprobe with high spatial resolution, together with long-term fluorescent and structural stability, powerfully tracked pH and Ca2 dynamics at the same localization in mitochondria in response to O2-- induced oxidative stress and aggregated amyloid β (Aβ) stimulation with a temporal resolution of milliseconds. Using this tool, we discovered that O2- and Aβ triggered transitory cytoplasmic acidosis and then activated acid-sensing ion channel 1a (ASIC1a) in the mitochondrial membrane, leading to mitochondrial Ca2 overload and pH abnormalities, which contribute to neuron death. Moreover, psalmotoxin 1 effectively protected against O2-- and Aβ-induced neuron injury.

Resume : Blood glucose concentration is a key factor of patients’ health, specifically for symptoms associated with diabetes mellitus. Electrochemically-sensing of glucose based on silver nanoparticles (Ag NPs) has been prominently used in the present of particular stabilizers for micro-sensor fabrication. Here, Ag NPs were electrodeposited on flexible carbon substrates where a laser-induced carbonization approach was employed to fabricate the highly-surface area patterns. Hierarchically-porous structure of carbon prevents further aggregation of Ag NPs and potentially improves the sensitivity of proposed electrodes based on amperometric responses. Indeed, the presence of Ag NPs with good electrocatalytic activity in cross-sectional regions causes a higher sensitivity and efficiency comparing to similar electrochemical sensing systems. Sensor fabrication was planned by immobilizing glucose oxidase on Ag NPs, and subsequently the practicability and analytical performance of hybrid electrodes were followed based on low detection and overpotential limits. Electrochemical responses to oxygen and sensing application to glucose were planned to analyze by cyclic voltammogram experiments. The proposed hybrid system could be also applied for fabrication of wearable glucose sensors and 3D-electrodes with other metal NPs.

Resume : Study on electrochemical properties of N-methyl-2-pyrrolidone exfoliation graphene tuned by salts -assisting Jian Shen, Piaopiao Wei, Kangbing Wu* Key Laboratory for Material Chemistry of Energy Conversion and Storage, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China First author. E-mail: jshen@hust.edu.cn * Corresponding author. E-mail address: kbwu@hust.edu.cn Solvent exfoliation is a convenient method to prepare high-quality graphene, developing methods with higher exfoliation efficiency is worthwhile and full of challenge. Hence, to improve the exfoliating efficiency of graphene, we prepared graphene by solvent exfoliation of graphite powder in N-methyl-2-pyrrolidone (NMP) with the assistance of three sodium salts, sodium citrate (Na3C6H5O7), sodium phosphate (Na3PO4) and sodium pyrophosphate (Na4P2O7), respectively. Uniform layer structure observed by scanning electron microscopy and transmission electron microscopy demonstrated graphite was successfully exfoliated into graphene. Through UV-Vis and Raman spectroscopies, it can be found that the three sodium salts can significantly improve the yield and defects of graphene, and Na4P2O7 has the best yield-increasing effect, which is about five times that of pure NMP. The electrochemical behavior of these graphene modified glassy carbon electrode (GCE) were systematically studied using a probe of K3[Fe(CN)6]. Through cyclic voltammetry and electrochemical impedance spectroscopy, it was confirmed that the salt-assisted solvent exfoliated graphene have larger electrochemical active area and stronger electron-transfer ability compared with the pure solvent exfoliated, and graphene prepared with Na4P2O7 (GS-4) shows the superior electrochemical performance. Further study using rotating disk electrode indicated that GS-4 has a highest standard heterogeneous rate constant (k0), means its high catalytic ability. The analytical application of the resulting graphene was studied. The modification of graphene, especially GS-4 greatly enhanced the oxidation currents of various analytes on GCE, such as small biomolecules (dopamine, urea, xanthine, hypoxanthine), phenolic pollutants (4-chlorophenol，4-nitrophenol), food colorants (ponceau 4R，rhodamine B), and dye (malachite green). Based on the signal amplification effect of graphene, a novel electrochemical sensor platform with high sensitivity of various substances was developed.

Resume : The research on carbon-based nanomaterials has received extensive attention. We designed and synthesized a range of carbon-based nanomaterials such as graphene, graphene quantum dots, functionalized carbon nanotubes, carbon nitride and their nanocomposites. We have constructed a series of electrochemical biosensors, colorimetric sensing platforms using the above carbon-based nanomaterials as electrode modification materials, signal carriers and catalytic materials, systematically studying the properties and performances of these carbon-based nanomaterials in the sensing field.

Resume : The accurate detection of multiple heavy metal ions holds a promising application in analyzing drinking water and it requires a low-cost, environmental-friendly and stable electrochemical sensor electrode. In this work, we controllably synthesize the undoped diamond(D)/graphite(G) nanoplatelet films as electrodes through manipulating microstructures and phase constituents, meanwhile, corresponding electrochemical properties have been successfully tailored from boron diamond feature to graphite feature. Investigated by high-resolution transmission electron microscopy and conductive atomic force microscopy, the D/G nanoplatelet is composed of insulated two-dimensional diamond nanoplatelet as a central stem and highly conductive graphite layers as shells. Attributing to the graphite edge planes with high electrochemical activity, the graphite shells establish a three-dimensional conductive and active network to accelerate the electrochemical reactions, however, which are also greatly influenced by adjacent diamond stem. It?s noteworthy that the undoped D/G-8% nanoplatelet film, with thick diamond stem encased into thin graphite shells (~ 4 nm), demonstrates wide potential window (3.18 V), low background capacitance (127.6 ?F cm-2) , which is much like boron doped diamond feature, nevertheless, it shows an improved electrochemical activity. Finally, arising from the widest working potential window and lowest background currents, the undoped D/G-8% nanoplatelet film is employed as the optimal platform for determination of Zn(II), Cd(II), Pb(II) and Cu(II) using differential pulse anodic stripping voltammetry method. Under the optimum conditions, wide linear ranges and high sensitivity are achieved. In the typical detection process, two linear working ranges are obtained due to the incomplete anodic removal and the limits of detection (LODs) are estimated to be 1.72 ?g L-1, 0.47 ?g L-1, 4.86 ?g L-1 and 0.45 ?g L-1 for Zn(II), Cd(II), Pb(II) and Cu(II), respectively. The simultaneous detections also verify the superior analytical performance with linear ranges from 10 ?g L-1 to 250 ?g L-1 and low LODs. The key results herein verify the D/G hybridized methodology is an effective undoped route towards structuring a nanocarbon electrode with good electrical conductivity, high electrochemical activity, as well as the merits of wide potential window, low background current and robust mechanical property, demonstrating the undoped D/G nanoplatelet electrode without any modification/functionalization has great potentials in the sensitive detection of trace heavy metal ions.

Resume : Wiley’s materials science portfolio boasts some of the top journals in this interdisciplinary field, including Advanced Materials (2017 impact factor 21.95), Advanced Energy Materials (2017 IF 21.87) and Small (2017 IF 9.59). Our in-house editorial staff are dedicated full time to handling your papers and providing high quality author services. This presentation will cover a little of what we can offer, as well as sharing some of our selection criteria to help you publish with us.

Resume : Carbon is usually used in energy storage and conversion devices due to their high electric conductivity, low cost, easy to control the structure and surface functionality. For example, graphite is a good anode material in lithium ion battery (LIB). Graphene is using for energy storage devices, but it is expensive and difficult to control its quality. We report here that natural graphite is processed to be graphene and anode material in LIB. Graphene may be used as new electrical conductive additives in cathode materials and also graphene based nano-composites with silicon or tin particles are high performance anode materials in LIB. We have proposed the nanostructured carbon concept, and report the low cost preparation graphene using natural graphite, and their applications of the nanostructured carbon in energy storage. Silicon particles were coated on graphene surface by CVD process and also mixed with nano-graphite sheet by air milling, content of silicon was around 30-40 wt.%, which was a very good candidate for anode application in LIB. If we mix it with graphite anode together at the ratio of 20-30 % (the mixture/graphite anode), the capacity could be 600-700 mAh/g and 500 cycles. Graphene was made from flake graphite by intercalation, exfoliation (at 200-300 oC in vaccum condition), and heat reduction. As prepared graphene was added into different cathode materials in LIB system, we found that it was only 20-50 wt.% used to replace current super P or carbon nanotubes, thus the volume energy density might be improved as 3-5% and enhanced the fast charge-discharge performance.

Resume : In order to prepare novel nanostructures with multi-functionalities and/or enhanced properties, one of the effective strategies is to adjust the electronic behavior in these nanomaterials, which could modify the binding energy, the d-band center and the charge distribution on the surface. Here, I will introduce our recent works in this field, from 2D noble metal to 2D carbon material: 1. Heterostructure fabrication in 2D Pd nanosheets. Ultrathin PdCu alloy nanosheets with various Cu/Pd atomic ratios were synthesized under mild experimental conditions. Meanwhile, the post-treatment of PdCu alloy nanosheets with ethylenediamine can dramatically enhance their electrocatalytic activity, exhibiting an excellent performance toward the formic acid oxidation compared to the previously reported Pd-based catalysts measured under similar conditions.[1] Moreover, the amorphous/crystalline Pd nanosheets are firstly synthesized and then used for enhancing the chemoselectivity.[2] 2. Site-defined doping in 2D graphdiyne. Breaking the bottleneck of random doping in 2D carbon nanomaterials, a new form of nitrogen atom, i.e., sp-hybridized nitrogen (sp-N) atoms, are site-defined doped into ultrathin graphdiyne for the first time by using the pericyclic reaction. The as-pre

Resume : Supramolecular assembly is a useful and powerful technique to tailor various ordered structures in nanometer length scales. Mesoporous silica is a representative material fabricated by utilizing the assembly of surfactant molecules as a soft template. The subsequent studies have developed a variety of mesoporous materials including mesoporous carbons. Recently, we have successfully prepared hierarchically porous resorcinol-formaldehyde (RF) resins embracing mesoporous nanorods with 2d-hexagonal periodicity by the one-pot sol?gel reaction using the soft-templating technique as well as phase separation. Several nanorods are connected to each other forming a macroporous network in submicron size, which is preserved through carbonization. In this study, we have applied the carbon monoliths with the abovementinoed pore hierarchy to an electrode for rechargeable Na-ion batteries. Effects of carbonization temperature on cyclic charge-discharge behaviors have been investigated. The electrochemical test results reveal that the carbon electrode heated at 1600 ºC delivers the highest reversible capacity higher than 360 mAh g?1 at 20 mA g?1. In addition, the corresponding electrode shows a fairly good cycle performance: the capacity retention at 200 mA g?1 after 200 cycles was determined as ~95%.

Resume : Energy storage devices are required not only to be lighter (mass-based energy density) and faster (rate performance), which nanotechnology have done very well, but also to be smaller (volume-based energy density), that is, storing more energy in a limited space, which the present nanotechnology rarely does well. In this talk, I will present how graphenes make energy storage devices smaller by densifying popcorn-like graphenes into hardtack-like porous carbons by a self-assembly technology, namely nano-densification of hydro-gelled graphene by interfacial capillary drying. I will talk about strategies, methods, materials, electrodes and devices in building compact energy storage devices including supercapacitors, lithium ion batteries and post-lithium ion batteries. (1) Y. Tao, Q.-H. Yang, et al. Sci Rep 2013, 3, 2975. (2) C. Zhang, Q.-H. Yang, et al. Energy Environ Sci 2015, 8, 1390. (3) Y. Xu, Q.-H. Yang, et al. Adv Mater 2015, 27, 8082. (4) H. Li, Q.-H. Yang, et al. Energy Environ Sci 2016, 9, 3135. (5) Y. Xu, Q.-H. Yang, et al. Nano Energy 2017, 36, 349. (6) H. Ma, Q.-H. Yang, et al. Small 2017, 13, 1701026. (7) L. Qin, J.-K. Kim, Q.-H. Yang, et al. Energy Storage Mater 2017, 9, 134. (8) H. Li, Q.-H. Yang, et al. Adv Energy Mater 2018, 1703438 (9) J. Zhang, D.-W. Wang, Q.-H. Yang, et al. Adv Energy Mater 2018, 8, 1702395. (10) J. Han, Q.-H. Yang, et al. Nature Commun 2018, 9, 402.

Resume : With the miniaturization of energy storage devices, volumetric energy density has become a critical parameter, but rarely emphasized in earlier studies of lithium-based batteries. The rise of noncarbon electrode (e.g. Sn and Si anode, S and O2 cathode) holds promise to improve the energy density of lithium batteries. However, the imprecise design of carbon cages to buffer noncarbon volume changes and block active material loss during cycling, which are the major obstacles to be overcome before the real applications, results in insufficient void space or much that cannot be used, greatly lowering the volumetric capacity. Here, we demonstrate a well-designed method to introduce an accurate amount of void space in three-dimensional graphene networks for noncarbons. In a typical synthesis using the capillary shrinkage of networked graphene hydrogels, flowable sulfur is used with the SnO2 nanoparticles inside the shrinking hydrogels, and the void space around SnO2 particles is precisely controlled by tuning the content of the surrounding and removable sulfur. This design fulfills the most stringent requirements for balancing the complete expansion of noncarbon anode and the high density of the graphene-caged noncarbon hybrids, and an ultrahigh high volumetric capacity (over 2100 mAh cm-3) is achieved. The precisely shrinking carbon cage also effectively blocks polysulfide dissolution in Li-S battery and accommodates the discharge products of oxygen in Li-O2 battery, and has been an ideal remedy for low volumetric energy density in post-lithium ion battery. 1. J. Han, Q.-H. Yang, et al. Nature Commun 2018, 9, 402. 2. H. Li, Q.-H. Yang, et al. Adv Energy Mater 2018, 1703438 3. L. Qin, Q.-H. Yang, et al. Energy Storage Mater 2017, 9, 134.

Resume : The primary phase of the light-molecule interaction is the photon energy absorption and deposition. Although the electron is much lighter than the nuclei, there is a strong electron-nuclear correlation for molecules exposed to strong laser fields. The photon energy deposits into the nuclei governs the succeeding dynamics and thus the fate of the molecules. Here, we experimentally reveal the correlated electron-nuclear dynamics by measuring the electrons and nuclear fragments ejected from a single molecule in coincidence. Our experimental results show that the electron and nuclei in a molecule share the absorbed multiphoton energy in a correlative manner [1,2]. The molecule as a whole absorbs the photon energy. The electron-nuclear energy sharing assisted by the rescattering lead to the observation of long-term predicted photon-energy spaced above threshold dissociation spectrum of breaking molecules [3], which is the interference of the periodically emitted electron-nuclear wave packet in the oscillating strong laser fields. Interestingly, for molecules in strong laser fields, a liberated electron can be recaptured by the ejected ionic fragments, leading to the formation of the excited Rydberg fragments. We real-time observe and further directionally control the dissociative frustrated double ionization of hydrogen molecules [4]. The frustrated double ionization of molecules can be generally understood in a multiphoton route by considering the correlated dynamics of electrons and nuclei of the molecule [5]. References [1] J. Wu et al., Phys. Rev. Lett. 111, 023002 (2013). [2] W. Zhang et al., Phys. Rev. Lett. 117, 103002 (2016). [3] P. Lu et al., PNAS 115, 2049 (2018). [4] W. Zhang et al., Phys. Rev. Lett. 119, 253202 (2017). [5] W. Zhang et al., Nature Communications 10, 757 (2019).

Resume : The printing technique is a method of printing a conductive ink on a general fabric to fabricate a fabric circuit, and is mainly printed on a conventional plastic substrate by a method of manufacturing metal such as carbon, copper, silver, nickel, and gold. If conductive ink is printed on textile, it can be applied to all kinds of textile without using weaving and knitting process by using conductive fiber and yarn. In addition, a flexible fabric circuit board can be developed. The development of a flexible fabric interface based on screen printing using a conductive material and the printing of the optimum viscosity of the binder, the number of printing times and the fabric thickness for the development of the clothing material for smart textiles. The optimum viscosity of binding solution was about 5600cP, and the printing was uniformly carried out while maintaining proper spreadability. As a result of an experiment according to the number of printing, it is found that as the number of printing is increased, the amount of conductive ink applied on the surface of the fabric increases, and consequently, the electric conductivity of the surface of the fabric increases. It was confirmed that maximum conductivity can be obtained by printing about 3 times. In printing by fabric thickness, the thinner fabric shows the lower the surface resistance value than that of thicker fabric. The developed conductive fabric exhibited a sheet resistance of about 0.2 ?. As a result of the durability test by washing and friction, it was confirmed that conductivity was maintained by washing and friction. Based on the results of this experiment, if the present study is successfully performed, the screen printing technology, which is mainly applied to the form of film and membrane, is applied to a fabric having voids to overcome limitations in application of fabrics, It is expected that the development of fabric interface for smart textiles with flexibility, light weight, durability and washability is expected to be possible.

Resume : Carbon sponge, a ground-breaking adsorbent with spatially controlled structure is demonstrated for targeting radiocesium and other radionuclides in agricultural soil. Three dimensionally porous carbon sponges originated from petroleum pitch exhibit high porosity and water permeability, resulting in highly efficient adsorbents for radionuclides in agricultural soil. It is also possible to enhance binding affinity and selectivity to radionuclide targets by decoration of carbon sponge surfaces with Prussian blue (PB) nanoparticles, and synthesized PB nanoparticles reveal low toxicity with potential advantages over eco-friendly applications. As a concept of the ?functionalized porous carbon?, the PB-decorated carbon sponges offer useful implications in the separation science of radioactive materials and important insight for designing novel materials for treatment of contaminated radioactive materials.

Resume : The corrosion resistance of silicon nitride-doped diamond-like carbon coatings has been examined using electrochemical and surface analyses techniques in Hank?s solution (pH 7.4 at 37 °C) used as the electrolyte to simulate the corrosive environment of body fluid. X-ray photoelectron spectroscopy performs shows that diamond-like carbon coatings doped with silicon nitride shows lower oxygen and higher carbon content, indicating that the deposited diamond-like carbon is likely more graphitic. Additionally, atomic force microscopy indicates that the surface become smoother and defects vanished with an increase of silicon nitride content. Furthermore, the electrochemical measurements shows that the diamond-like carbon coating doped with silicon nitride could improve the corrosion resistance in a simulated body fluid environment due to higher pitting corrosion resistance, coating and charge transfer resistance.

Resume : Improvement of anode chamber of molten sodium hydroxide direct carbon fuel cell (MHDCFC) of fuel utilization is a kind of currently the most effective and cheapest chemical process research method by CFD simulation. However, Anode chamber of MHDCFC suffers a large activation polarization loss because of the sluggish kinetics of the electrochemical oxidation of carbon. So I design a anode chamber of MHDCFC used in power plants to produce electricity. By comparing different types of carbon materials, the effect of carbon particles on the flow path of molten sodium hydroxide direct carbon fuel cells was found by CFD simulation, including hard coal, brown coal, carbonized biomass, graphite, carbon black etc. Because different carbon materials behave in different specific surface area, density, and particle size, these physical parameters have a huge impact on the electrochemical performance of anode chamber of molten sodium hydroxide direct carbon fuel cell. According to Reynolds's law and Einstein's equation, different carbon materials have an effect on the mass transfer of the entire anode chamber channel. Through simulation calculation, the influence of the size of the anode fuel carbon particles on the convective diffusion in the flow directly affects the electrochemical performance of the anode. The distribution of carbon particles on the surface of the current collector directly affects the utilization of the anode carbon particles and reduces the concentration polarization.

Resume : CNWs(Carbon Nanowalls) have wide surface and wall structure-based dual detection as catalyst-free 2-Dimension carbon material with multi-layer vertical graphene. CNWs widely were utilized to biosensor, gas sensor and sensor having electrochemical method due to these properties. However, 2-Dimension carbon nano materials like CNWs has disadvantage being absented of functional group on surface. For solving this limitation, activation of functional group with modifying surface became fundamental. We focused on modifying surface to CONWs(Carbon Oxide Nanowalls) and rCONWs(Reduced Carbon Oxide Nanowalls). And we researched to detect liquid organic solvent such as acetone, ethanol, methanol and toluene by using CONWs and rCONWs. The morphology of CONWs and rCONWs were identified through FE-SEM(Field Effect Scanning Electron Microscopy). The XPS(X-ray Photoelectron Spectroscopy) and FT-IR(Fourier Transform Infrared Spectroscopy) were used to verify component and binding properties by functional group of CONWs and rCONWs. Additionally, we studied electrical change property and sensor performance according to liquid organic solvent on surface of CONWs and rCONWs.

Resume : The employment of an epitaxial cubic SiC film as a photocathode is proposed for photoelectrochemical water splitting. Under visible light irradiation, high current density and superior incident photo to current conversion efficiency for water splitting(hydrogen evolution) is achieved on this photocathode. Such performance results from the high phase purity, low resistance, and negative conduction band energy level of this SiC film level as well as its strong capacity of visible light absorption.

Resume : Many types of modern electrochemical applications use thin flexible conductive films. Carbon nanotube (CNT) films have satisfactory optical and electrical parameters, as well high mechanical and thermal stability. The addition of a conductive polymer to a CNT film can significantly reduce the contact resistance between individual CNT?s and increase the transparency - surface resistance ratio. The possibility of layer-by-layer formation of composite films with enhanced conductivity based on the system of CNT?s - conducting polymer using the in-print method is demonstrated. The main advantage of the films obtained is the mechanical stability to bending deformations. The impedance characteristics of functionalized materials based on modified CNT films were studied. A numerical method is proposed, which makes it possible to approximate the distribution functions of the relaxation times of active R, reactive C and L elements of samples directly from the experimentally obtained frequency dependence of the real and imaginary components of the impedance. The films obtained are characterized by a combination of low surface resistance (156 ohms/sq.) and low optical transparency (~ 32 %). It is shown that with increasing concentration of CNT?s, an increase in the electrical conductivity of the samples under study is observed.

Resume : Monolithic carbon xerogel(MCX) with co-continuous hierarchical porosity was prepared via one-step, template-free and catalyst-free hydrothermal polycondensation reaction with resorcinol(R) and formaldehyde(F), and subsequent pyrolysis and CO2 activation. The reaction was carried out in a pressurized Teflon mold at 100 °C for 6 h, while the F/R (2.2, 2.4, 2.6, 2.8) and R/W ratios (40, 45) were varied to afford co-continuous pore structure with interconnected carbon particles. Then, the gels were dried at 60 °C for 36 h and then 100 °C for 12 h, generating xerogels which were subjected to pyrolysis at 900 °C for 2 h and CO2 activation at 1000 °C for 2, 4 or 6 h. Among the gels, co-continuous pore structure with interconnected particles was observed only from those with F/R=2.4 and 2.6 at R/W=40 as well as R/F=2.2 at R/W=45, but the gel with F/R=2.4 at R/W=40 was only one with no crack generation upon 6 h CO2 activation. Thus, this gel was subjected to N2 sorption study, providing specific surface area(SSA) of 1418, 2489 and 3418 m2/g for 2, 4 and 6 h activation, respectively, being attributed to introduction of micro-pores via the activation which also generated meso- and macro-pores, forming hierarchical porosity. Electrochemical property of these gels were also evaluated.

Resume : Recently, the use of three-dimensional (3-D) graphene networks in polymer matrices has attracted a great deal of interest as a new strategy for fabricating highly flexible and conductive graphene-based polymer nanocomposites. In the present work we?ve investigated 3-D continuous network structures based on graphene ellipsoids and the effects of their pore morphology on the electrochemical properties of their polymer composites. For that matter, the hollow graphene ellipsoids and the free-standing graphene films based on 3-D continuous structures of hollow graphene ellipsoids were fabricated and their properties were examined in terms of the structural factor. In order to obtain graphene ellipsoids, positively charged polystyrene (PS) spheres were first wrapped with negatively charged graphene upon simple mixing, and the assembly of core-shell spheroids were transformed to ellipsoids by unidirectional stretching. Graphene-wrapped PS ellipsoids were assembled into films by simple jet-spray coating, and finally, careful calcination of the graphene-PS assembly film resulted in successful formation of 3-D network of hollow graphene ellipsoids. Due to their improved continuity, composites based on the ellipsoids have lower sheet resistances than those based on spherical nanoparticles. Upon folding and application of pressure, composites based on the hollow graphene ellipsoids exhibited superior electrical conductivity and structural stability owing to their high mechanical strength and effective electron transport pathway. The ability to control the face-contact structures of graphene in a polymer matrix by means of particle morphology represents an effective strategy for future nanomaterial-involved engineering.

Resume : Nanoscale carbon dots (CDs) have drawn increasing attention owing to their many merits including excellent optical, electric and photoelectric properties. In this work, a practical strategy is proposed to improve the photoelectrical response performance of CDs by taking advantages of the synergistic effect of nitrogen and sulfur co-doping and copper phthalocyanine non-covalent functionalization approaches, which rightly adjusts the energy level of CDs, optimization of intimate interfacial contact, extension of light absorption range, and enhancement of charge-transfer efficiency. This work demonstrates that heteroatom doping and chemical functionalization can endow CDs with various new and improved physicochemical, optical, and structural performances. This synergy contributes enormously to the molecular imprinting photoelectrochemical sensor for Ochratoxin A (OTA) detection.

Resume : An innovative material as anodic carbon fuel for molten hydroxide direct carbon fuel cell Xiaofeng Li,Yanfang Gao,* College of Chemical Engineering, Inner Mongolia University of Technology, Hohhot, 010051, P.R. China * E-mail:yf_gao@imut.edu.cn The direct carbon fuel cells (DCFCs) belong to new generation of energy conversion devices that are characterized by much higher efficiencies and lower emission of pollutants than conventional coal-fired power plants.[1]Over the past several decades fuel cell technologies have been treated as promising candidates for various utility applications.Today fuel cells are still considered an environmentally friendly and highly efficient electricity generating systems and extensive research has been conducted worldwide to improve this technology.The direct carbon fuel cell (DCFC) is a unique type of fuel cell able to convert efficiently the chemical energy of solid carbonaceous fuels directly into electricity without the combustion of the fuels. The theoretical maximum efficiency of carbon conversion in the DCFC is 100%,but practical efficiencies have been demonstrated at roughly 80% [2]. The molten hydroxide direct carbon fuel cell uses molten hydroxide (NaOH or KOH) as the electrolyte which is contained within a metallic container which also acts as a cathode. A carbon rod made from graphite or coal derived carbon is dipped into the electrolyte and used as both the fuel and anode of the cell.Such a system was considered to have a number of advantages over the molten carbonate electrolyte DCFC. The advantages of using sodium hydroxide electrolyte include high ionic conductivity (especially when associated with water) [3,4], high reactivity towards carbon [5] and a low melting point [6]. Nanostructured Ceria-Silver is a rice-ball nanostructure,[7]that is an innovative catalyst concept with a configuration that is inverted relative to that of a conventional supported catalyst, which has a ?sushi?-type structure.Carbon oxidation is supposed to be efficiently promoted by maximizing the silver-ceria interface to activate oxygen species, increasing the contact between ceria and carbon to facilitate spillover of active oxygen onto the carbon at large distances,and covering silver with ceria particles to prevent silver sintering.The nanocatalyst with special structure was mixed with lignite pyrolysis carbon to enhance the oxidation activity of anodic carbon fuel,and the mixture is acted anodic carbon fuel for molten hydroxide direct carbon fuel cell. References [1] Giddey S , Badwal S P S , Kulkarni A , et al. A comprehensive review of direct carbon fuel cell technology[J]. Progress in Energy and Combustion Science, 2012, 38(3):360-399. [2] J.F. Cooper, Presented in Direct Carbon Fuel Cell Workshop, NETL, Pittsburg, PA, USA, 30th July, 2003, Proceedings online: http://www.netl.doe.gov/publications/proceedings/03/dcfcw/Cooper.pdf. [3] Pesavento PV, Carbon-Air fuel cell. US Patent office, patent no. 6, 200, 697,2001. [4] Eberz A , Franck E U . High Pressure Electrolyte Conductivity of the Homogeneous, Fluid Water-Sodium Hydroxide System to 400°C and 3000 bar[J]. Berichte der Bunsengesellschaft für physikalische Chemie, 1995, 99(9):1091-1103. [5] Claire Hérold, Albert Hérold, Lagrange P . Ternary graphite intercalation compounds associating an alkali metal and an electronegative element or radical[J]. Solid State Sciences, 2004, 6(1):125-138. [6] FTsalteFACT Salt Phase Diagrams, Centre for Research in Computational Thermochemistry (CRCT), Facility for the Analysis of Chemical Thermodynamics FACT), 2012. http://www.crct.polymtl.ca/fact. [7] Kayama T , Yamazaki K , Shinjoh H . Nanostructured Ceria?Silver Synthesized in a One-Pot Redox Reaction Catalyzes Carbon Oxidation[J]. Journal of the American Chemical Society, 2010, 132(38):13154-13155. Biography Yanfang Gao has completed her PhD at the age of 30 years from Fukui University and postdoctoral studies from Tsinghua University of Chemistry. She is a professor at the department of Inner Mongolia University of Technology,a tutor of a phD student.She has published more than 20 papers in reputed journals. Presenting author details Full name: Xiaofeng Li Contact number: +86 13081512254 Session name/ number: European Materials Research Society Category: Poster presentation

Resume : High-volumetric-performance supercapacitors are increasingly in demand for compact devices in electric and electronic systems.[1] Activated carbons as promising supercapacitor materials are rich in porosity and well-established commercially, but their volumetric performance is significantly restricted by their low density. Recently, our group has developed a high density porous carbon resulting from the compact interlinking of 2 ~ 4 layered graphene nanosheets.[2] Inspired by the dense structure of irregular pomegranate grains, we propose a simple yet effective approach to pack activated carbons into a compact graphene network with graphene as the “peels”.[3] The capillary shrinkage of the graphene network sharply reduces the voids between the activated carbon particles through the microcosmic rearrangement while retaining their inner porosity. As a result, the electrode density increases to 1.9 times that of pure AC. Such a graphene-assisted densification strategy can be extended to the densification of other carbon or non-carbon particles for energy devices requiring a high volumetric performance. Furthermore, to our best knowledge, as the first densification strategy reported for commercial ACs, this method is simple and easily scalable (3L), promising to accelerate the development of industrial supercapacitors with higher volumetric energy densities. [1] H Li, Y Tao, J Luo*, Q-H Yang*, et al. Energy Environ. Sci. 2016, 9, 3135 [2] Y Tao, X Xie, W Lv, Q-H Yang*, et al. Sci. Rep. 2013, 3, 2975 [3] P Li, H Li, D Han, Y Tao*, Q-H Yang*, et al. Adv. Sci. 2018, Under Review

Resume : Adhesion between the two materials is changed by chemical and physical bonding and effects the electrical properties of materials. In this respect, it was confirmed that the adhesion between the carbon nanowall and the substrate was poor, and the electrical characteristics were changed by the external stress. Therefore, in this study, TCO (Transparent Conducting Oxide) was used as an intermediate layer to improve the adhesion of carbon nanowall. The 4-inch TCO targets such as ITO (Indium Tin Oxide), AZO (Aluminum Zinc Oxide), GZO (Gallium Zinc Oxide) and ZnO (Zinc Oxide) were used and the TCO-based interlayer was synthesized on substrate by using RF magnetron sputtering system. Carbon nanowalls were grown on the interlayer coated substrate by a microwave plasma enhanced chemical vapor deposition (MPECVD) system with a mixture of methane (CH4) and hydrogen (H2) gases. An ultrasonic cleaner was used to confirm adhesion between carbon nanowall and substrate in fabricated the carbon nanowall/interlayer/substrate structure. Afterward, the changes of the surface morphology according to the interlayer were confirmed by FE-SEM (Field Emission Scanning Electron Microscope), AFM (Atomic Force Microscope), and contact angle analysis, and then electrical and optical properties by the ultrasonic cleaning were investigated by using a Hall measurement and UV-visible, respectively.

Resume : Carbon materials have attracted intense interests as electrode materials for electrochemical capacitors, because of their high surface area, electrical conductivity, chemical stability and low cost. Activated carbons produced by different activation processes from various precursors are the most widely used electrodes. Recently, with the rapid growth of nanotechnology, nanostructured electrode materials, such as carbon nanotubes and template?synthesized porous carbons have been developed. Their unique electrical properties and well controlled pore sizes and structures facilitate fast ion and electron transportation [1]. Thus, building hierarchically porous architectures comprising of micropores, mesopores and macropores in carbon materials is regarded as an effective way to construct high-performance supercapacitors [2]. Chitosan contains a large number of amino groups, so nitrogen self-doped hierarchical porous carbon material were synthesized for supercapacitor electrode application by using chitosan as a precursor and montmorillonite as a template through a carefully controlled hydrogel formation-carbonization-activation process. Montmorillonite is a low-cost natural clay with layered structure and high surface area [3]. The main reasons for choosing it as a template are its low price, wide source, easy intercalation and environmental friendliness. The carbonized products without activation were tested by electrochemical method. According to the cyclic voltammetry curves, it can be seen that the material has obvious rectangular shape, which indicates that the material has good double layer behavior. According to the constant current charge-discharge curve, the specific capacitance is 137Fg-1 when the current density is 0.5Ag-1. Because the activation process can effectively improve the specific surface area and pore volume of carbon materials [4]-[5], so this material may have good electrochemical properties after activation. ????? [1]Zhai Y , Dou Y , Zhao D , et al. Carbon Materials for Chemical Capacitive Energy Storage[J]. Advanced materials (Deerfield Beach, Fla.), 2011, 23(42):4828-4850. [2]Li B , Cheng Y , Dong L , et al. Nitrogen doped and hierarchically porous carbons derived from chitosan hydrogel via rapid microwave carbonization for high-performance supercapacitors[J]. Carbon, 2017, 122:592-603. [3]Maiti S , Pramanik A , Chattopadhyay S , et al. Electrochemical energy storage in montmorillonite K10 clay based composite as supercapacitor using ionic liquid electrolyte[J]. Journal of Colloid and Interface Science, 2015, 464:73-82. [4]Ioannidou O , Zabaniotou A . Agricultural residues as precursors for activated carbon production?A review[J]. Renewable & Sustainable Energy Reviews, 2007, 11(9):1966-2005. [5]Liu D , Zhang W , Lin H , et al. A green technology for the preparation of high capacitance rice Husk-based activated carbon[J]. Journal of Cleaner Production, 2015, 112:1190-1198.

Resume : The electronic devices based on textiles (e?textile) have been attracted attention because the interest in portable and wearable electronic devices has been gradually growing. In particular, e-textiles for gas sensing can be applied in the various fields such as military, construction, and fire scene. Here, we report the flexible and portable toxic gas sensor based on e?textile using pyrolysis of graphene oxide (GO)-coated commercial silks. The GO on the surface of the e-textiles was reduced by thermal treatment at 400, 500, and 600 ? to endow electrical conductivity. The responses of sensors are about 10 % and 30 % under 5.0 and 10 ppm of NO2, respectively when thermal treated at 400 ? and 15% and 30 % when thermal treated at 500 ?. We also found that the 6 % of response to SO2 under 1.0 and 2.0 ppm of SO2 was achieved with the e-textile treated at 600 ?. Moreover, we synthesized the nanoparticle-embedded GO with copper, silver, tin, and zinc to increase the response of gas sensing property. Using these materials, we fabricated gas sensors and detected NO2 and SO2. We confirmed that response of sensors was increased compared with pristine GO.

Resume : Graphite carbonitride (g-C3N4) is considered to be a promising, widely used heterogeneous catalyst due to its good electrical conductivity and excellent catalytic performance. Incorporation of metals or non-metals can form new composite materials possessing the properties of each component with a synergistic effect that would greatly enhance their catalytic performance, which are of great importance in particular applications. In this work, we successfully synthesized a composite material Fe-g-C3N4 with peroxidase-like activities by an in situ growth method and used it for colorimetric detection of hydrogen peroxide. The limit of detection was calculated as low as 1.8 µM (S/N = 3). The powder X-ray diffraction (XRD), transmission electron microscopy(TEM) , X-ray photoelectron spectroscopy(XPS)?Fourier transform infrared spectroscopy(FT- IR) and atomic force microscopy (AFM) characterizations of the Fe doped carbon nitride nanocomposites suggest that a novel nanozyme has been successfully synthesized without changing the graphitic stacking structures. The nanoparticles can also act as mimicking enzymes including horseradish peroxidase and show higher affinity to the 3,3?,5,5?-tetramethylbenzidine (TMB)-hydrogen peroxide (TMB-H2O2) system than natural horseradish peroxidase or the reported molecule oxidase mimic. That is to say that it can be used to indirectly detect substances that can produce hydrogen peroxide, such as glucose and sarcosine. It is believed that due to their excellent catalytic performances and stability, they will greatly promote the practical applications of Fe-g-C3N4 as enzyme mimics in a variety of applications in the future.

Resume : A novel electrochemical assay based on graphene@ZIF-8 hybrids templated gold nanoclusters (AuNCs-GR@ZIF-8) and DNAzyme decorated cascade-like layered-branched hybridization chain reaction (LB-HCR) was constructed for ultrasensitive interferon-gamma (IFN-?) detection. The target-triggered cascade-like assembly of four hairpins in LB-HCR process caused the generation of dendritic DNA nanostructures with in-situ formed hemin/G-quadruplex DNAzymes as amplifying labels. This multiple-amplified strategy provided a new pattern for the construction of electrochemical platform with high sensitivity.

Resume : The carbon quantum dots derived from biological sources showed much interest in biomedical applications due to their biocompatibility. Eichhornia crassipes (water hyacinth) biomass is a sustainable resource, which has the potential to produce diverse applications. This paper reports for the first time the synthesis of carbon quantum dots (CQDs) from water hyacinth as a new carbon source via facile one-pot hydrothermal route in acetic acid. The CQDs are monodispersed and quasispherical in shape, with blue emission and quantum yield of 5.24%. Selective diffraction pattern confirmed the crystallinity of the CQDs while the infrared spectra showed the presence of aromatic carbon core and surface functionalities of hydroxyl and carbonyl groups. The CQDs were then tested for cellular imaging with freshly grown Allium cepa and E. coli cells, showing visible cell walls and nucleus compared to using reference dye. Cytotoxicity results indicate the biocompatibility of the CQDs for the living cells. More significantly, this method offers a possibility for large scale production and an opportunity to modify and tune the surface functionalities, sizes and photoluminescent characteristics of the carbon quantum dots by the biofunctionalization and conjugation techniques.

Resume : Carbon dioxyde should not be seen anymore as a waste but as an alternative carbon feedstock to produce platform chemicals and energy carriers. In this context, the carbon capture and recycling appears as a key challenge. Biocatalytic processes appear as promising alternatives, as they run on relatively mild conditions, are ecologically-friendly and highly selective. Few biocatalysts including enzymes and bacteria have been studied for the conversion of CO2. Amongst them, formate dehydrogenases (FDHs) have been widely used. Most FDHs require a loosely bound cofactor (NAD) in its active reduced form, 1,4-NADH. As NAD is relatively unstable and expensive, it has to be regenerated in situ. To do so, the direct electrochemical regeneration of 1,4-NADH, involving direct transfer of potentially cheap electrons from electrode surface to NAD, looks as challenging as promising. In this context, we developed a novel method to covalently immobilize NAD onto carbonaceous materials, in particular onto multi-walled carbon nanotubes. Such functional carbons were then employed as support for FDHs and tested for the bio-electrochemical reduction of CO2 into formate. In this communication, we will present and discuss our latest results regarding the enzymatic electrosynthesis of formate from CO2.

Resume : In our work, a single layer graphene was synthesized by chemical vapor deposition (CVD) at 1000 °C and n-doped by vapor phase molecular doping at 70 °C. Raman spectroscopy was used to analyse doping level, and electrical properties were measured by field effect transistors. To demonstrate a stable n-doped graphene and to find out how the molecular structure of the dopant affects its strength and stability, we selected linear aliphatic diamines and aromatic diamines as dopants. Selected linear aliphatic diamines are ethane-1,2-diamine (EDA), propane-1,3-diamine (PDA), butane-1,5-diamine (BDA) and Hexane-1,6-diamine (HDA). And Selected aromatic diamines are p-Phenylenediamine (PPD) and o-Phenylenediamine (OPD). There are several key variables in this model system. The longer carbon chain of a diamine molecule can reduce the electron transfer per unit area of graphene. The molecular geometry is also significant. Since these are linear aliphatic compounds, amine groups always face different orientations. The difference in orientations of amine groups depends on the length of a carbon chain. The results of this work on diamines and vapor phase doping system help to improve and stably maintain the electrical properties of graphene.

Resume : A fuel cell is a device that directly converts chemical energy into electrical energy. Because it is not limited by the Carnot cycle, its theoretical efficiency can reach 100%[1]. Fuel cells have attracted much attention due to a series of advantages such as high conversion efficiency, wide fuel sources, and no pollution[2]. The slow kinetics of the cathode oxygen reduction reaction of fuel cells seriously restricts its development. At present, platinum is the optimal choice for oxygen reduction catalysts, but because of its high price, it has become a bottleneck for the large-scale commercialization of fuel cells. It is seeking to reduce amount of platinum used to replace platinum catalysts is imminent. Cerium oxide is a wide range of rare earth materials with storage and a large amount of oxygen release. It is mainly determined by the lattice oxygen deficiency of CeO2, and its special properties are favored[3]. It has been pointed out in the literature that platinum and cerium oxide can improve the performance of the catalyst because Ce3+ in cerium oxide inhibits the formation of platinum oxide by conversion to Ce4+ and platinum and cerium oxide together constitute an electron transport leading to improve catalytic performance[4-5]. On this basis, 3d transition metal Co was introduced to further enhance the catalytic effect of the catalyst. The experimental results show that the Pt-Co-CeO2/CNT catalyst has a half-wave potential of 0.89V. Its electron transfer number is close to 4 and the cycle stability is also higher than that of Pt-CeO2/CNT. The formation of an alloy changes the d energy band of platinum, thereby changing the adsorption energy of the intermediate products which improve the catalytic performance of oxygen reduction. References [1]Kacprzak A, Koby?ecki R, W?odarczyk R, et al. Efficiency of non-optimized direct carbon fuel cell with molten alkaline electrolyte fueled by carbonized biomass[J]. Journal of Power Sources, 2016, 321:233-240. [2]Giddey S , Badwal S P S , Kulkarni A , et al. A comprehensive review of direct carbon fuel cell technology[J]. Cheminform, 2012, 38(3):360-399. [3]Chu Y Y , Cao J , Dai Z , et al. A novel Pt/CeO catalyst coated with nitrogen-doped carbon with excellent performance for DMFCs[J]. Journal of Materials Chemistry A, 2014, 2(11):4038-4044. [4]Masuda T, Fukumitsu H, Fugane K, et al. Role of Cerium Oxide in the Enhancement of Activity for the Oxygen Reduction Reaction at Pt?CeOx Nanocomposite Electrocatalyst : An in Situ Electrochemical X-ray Absorption Fine Structure Study[J]. Journal of Physical Chemistry C, 2012, 116(18):10098-10102. [5]Chu Y Y , Wang Z B , Jiang Z Z , et al. A Novel Structural Design of a Pt/C-CeO2 Catalyst with Improved Performance for Methanol Electro-Oxidation by ?-Cyclodextrin Carbonization[J]. Advanced Materials, 2011, 23(27):3100-3104.

Resume : The ability to monitor CO2 is crucial for personal safety and medical reasons because at levels above 5 % CO2 becomes toxic. We propose a RF gas sensor based on an EMBG (electromagnetic band gap) resonator working at 22 GHz covered in the center area with a 10 ?m thick multiwall carbon nanotube (MWCNTs) layer. The CNT-EMBG based resonator is able to detect carbon dioxide by changes in the resonance frequency. The EMBG structure was fabricated on a 500 nm SiO2/525 ?m /HR Si wafer and 500 nm gold metallization. MWCNTs from Nanolab US have the following proprieties: 30 nm average diameter, 5-20 ?m length, 95% purity and were used without any further purification, then they were dispersed at a concentration of 10 mg/ml in a solvent mixture based on dimethylformamide (99.8%, anhydrous, Sigma Aldrich) and cyclohexanone (99.8%, Sigma Aldrich) in a volume ratio of 2/1. In a successive step, the MWCNTs dispersion solutions were de-bundled by sonication at combined frequencies 25/45 kHz for one hour and let overnight to check the stability. The experimental results demonstrate a shift in the resonance frequency of about 209 MHz using MWCNTs for CO2 detection. The interaction between CO2 molecules and MWCNTs allows to obtain a very high value of sensitivity, i.e. 64.78% for 0.72% CO2. This result, together with the compact dimensions of the device, is a further proof of the CNTs high capabilities of gas sensing. Acknoledgements; We are grateful for financial support of H2020 project NANOSMART.

Resume : Sulfur-carbon bridged materials (sulfur-doped carbon and sulfurized carbon) show high excellent energy storage performance in both Na-ion battery system and Na-S battery system. However, the low preparation efficiency and unclear electrochemical energy storage behaviors have hampered more extensive study. Herein, we develop a one-step annealing strategy to achieve high covalent sulfur-carbon bridged complex (HCSC) through utilizing phenylphosphinic acid as the carbon-source/catalyst and sodium sulfate as the sulfur-precursor/salt template. Notably, most of the bridge bonds are electrochemically cleaved as the cycling voltage is lower than 0.6 V versus Na/Na . The in-situ and ex-situ techniques demonstrate that S2- is formed in the reduction process and the carbon skeleton is concomitantly and irreversibly isomerized. Inspired by these results, we further develop a novel strategy to prepare covalent sulfur-carbon complex (SC-BDSA) with high covalent-sulfur (40.1%) that relies on -SO3H and SO42- as the sulfur source rather than elemental sulfur. The C-Sx-C bridges could be electrochemically broken at lower potential (< 0.6 V versus Na/Na ) and then worked as a capacity sponsor. And the R-SO units can anchor the initially generated Sx2- to form insoluble surface-bound intermediates. Thus, the activated SC-BDSA exhibites a specific capacity of 1050 mAh g-1 at 250 mA g-1 and excellent cycling stability for 1000 cycles with 0.035% capacity decay per cycle at 2500 mA g-1. The analogous electrochemical phenomenon is also noticed at the different potential window versus Li/Li . These results avove provide novel strategies to prepared sulfur-carbon bridged complex, and reveal an improved enlightenment on the interfacial chemistry of electrode materials, which are beneficial for the design and manufacture of rechargeable RT Na-S battery system.

Resume : These days, many portable electronic devices are used widely. It makes secondary batteries important for future innovation. Li-ion battery which is most commonly used has problems with high price and possibility of explosion and also it reaches the limitations of energy density. So Li-S battery is becoming a one of the promising alternatives. It has high theoretical energy density and low cost. Also it is eco-friendly and safe. However, there is the primary problem to be commercialized. That one is called shuttle effect, which means dissolution of polysulfides into the electrolyte in the repetitive charging and discharging. It makes capacity decrease and internal resistance increase. To minimize the shuttle effect, we modified ordered mesoporous carbon(OMC) materials. Carbon materials which have good conductivity are used with sulfur since the sulfur is non-conductive. Especially the OMC has high thermal and chemical stability, high surface area and high pore volume. First, we synthesized the OMC materials with micropore by introducing silica nanoparticles. We expected that polysulfides with long chain could be blocked due to the small pore size. In the second place, we loaded metal nanoparticles on the OMC. Nanoparticles of platinum could catalyze the reaction of polysulfides so dissolved polysulfides could be trapped. The materials were characterized by X-ray diffraction(XRD), N2-sorption, scanning electron microscope(SEM), and energy dispersive X-ray(EDS).

Resume : The spontaneous collapse of large-diameter single carbon nanotubes (SWCNTs) generates a new class of low dimensional structures, known as collapsed ?dogbone? nanotubes. Several experimental works showed that the final configuration of collapsed tubes is composed by two flat nanoribbons, whose edges are closed forming chemical bonds like the standard carbon nanotubes. Our first-principle investigation based on the Density Functional Theory (DFT) revealed how these flattened tubes become more stable than its own cylindrical counterpart when a given diameter threshold is exceeded. A peculiarity of these hybrid systems between bilayer graphene and SWNTs due to their unique architecture is the possibility to fill the edge cavities with different molecules. The radial deformation of filled nanotubes is driven by changes in the charge transfer process between molecular species and surrounding carbon edge channels. The edge filling implies Coulomb interactions between molecules and molecules and CNT-like zone at the edges. The filled cavities induce doping effect on the collapsed nanotubes without the introduction of defects and/or scattering centres with really significant improvement of the electrical conductivity. Such innovative systems represent a rising star on the horizon of nanomaterials science, because of peculiar mechanical and electronic properties, opening the path to promising deformed graphene based on high-performance nanoscale devices.

Resume : Recent theoretical and experimental studies have suggested that heteroatom-doped graphene nanosheets as emerging materials with exceptional optoelectronic properties for applications including nanoelectronics, energy storage, fuel cells, and electrochemical sensing. Beside those applications, graphene-enhanced Raman scattering (GERS) is a new phenomenon and has attracted intense interest recently. Because of the unique 2D heteroatom-doped sp2 carbon structure, graphene provides particularly enhanced Raman signals for molecules adsorbed on its surface. However, current synthesis methods of heteroatom-doped graphene nanosheets usually involve complicated vacuum systems and time-consuming process, making it difficult to enable industrial-scale production. Consequently, the development of a facile and controllable synthesis of heteroatom-doped graphene nanosheets will lead to important advances in both scientific studies and innovation applications. Here we report the production of few-layered heteroatom-doped graphene nanosheets with varying dopant types and controlled concentration by an efficient solid phase mechanochemical exfoliation of graphites using ball milling. Ball milling has many advantages, such as time-saving, easy to operate, safe, non-polluting. The physical principle of the ball mill which is provided sufficient energy to weaken the van der Waals interactions and promoted the intercalation of solvent molecules into the graphene sheets within bulk graphites. At this moment, the foreign atom we added will change the graphene original structure and it will improve the optoelectrical properties and enhance the Raman signals. Detailed materials characterizations including transmission electron microscopy, UV-Vis spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and Atomic force microscopy suggest that boron-, nitrogen-, sulfur-, and phosphorus-doped few-layer graphene nanosheets with varying dopant concentrations were successfully prepared. In our work, we successfully confirm that the as-prepared heteroatom-doped graphene nanosheets process the GERS properties.

Resume : Carbon materials have received intensive attention due to their tunable electrochemical activity and charge-storage properties in terms to electrochemical applications, however, a versatile electrochemical platform for multi-purpose applications, such as catalysis, energy storage and sensing basing a functional carbon nanostructure is rarely reported until now. Herein, an in-situ self-growth NaCl-templated strategy is proposed to fabricate three-dimensionally (3D) honeycomb-like porous Ni, N-codoped carbon materials (Ni-N-C). The as-obtained 3D Ni-N-C demonstrates excellent electrocatalytic activity toward the reduction of oxygen with a high onset potential about 0.85 V vs the reversible hydrogen electrode (RHE) and large limiting diffusion current. A high specific capacity (~160 F/g at 0.25 A/g) and stability is also obtained as electrical double layer capacitor electrode material. Moreover, the 3D Ni-N-C also shows good sensitivity toward glucose and H2O2 detection. It is believed that the unique structural properties of 3D Ni-N-C (abundant N-doped and Ni-N coordinated active sites, large surface area, open micro-porous structure, and short diffusion paths) are conducive to the formation and exposure of highly catalytic centers and improvement of electron-transfer and charge-storage ability. This work is a successful case to make the most of the structure advantages of carbon material to achieve energy sustainable development and biosensing.

Resume : The biggest issue of hydrogen production via electrolysis is that how the noble metal catalysts to be replaced. One of the possible candidate materials is MoS2 because it has high active area and hydrogen adsorption Gibbs free energy. In this research, we developed electrode replacing noble metal by using graphene and MoS2. graphene was synthesized on stainless steel (SUS) substrate for electron transfer layer using CVD method. Then, MoS2 was synthesized on top of graphene layer. The graphene and MoS2 on SUS substrate was confirmed via Raman and X-ray photoelectron spectroscopy. Electrochemical experiments were carried out under three different electrolytes (KOH, NaCl, H2SO4). The results, indicate that MoS2/Graphene/SUS has an onset potential of -116mV, current density of 100 mA/m2, and Tafel slope of 62mV/dec. Moreover, hydrogen production was quantified by using GC-TCD, and it showed 80% of hydrogen production efficiency. This research was supported by the Nano·Material Technology Development Programthrough the National Research Foundation of Korea (NRF), funded by the Ministry of Science and ICT (2016M3A7B4904328).

Resume : Water electrolysis is one of the most reliable hydrogen production methods due to capability of producing high purity hydrogen. However, the biggest problem of water electrolysis is the high production cost of hydrogen, which can be improved by increasing the electrode surface area with synergistic effect of catalyst component. Among the electrode materials to replace this, carbon cloth is suitable for use due to its inherent characteristics. However, it is difficult to show good efficiency of the hydrogen evolution reaction only by the carbon cloth. In this study, MoS2 was used as a catalyst for hydrogen evolution of the carbon cloth electrode and MoO2 was added together to reduce the electrical resistance of MoS2 catalyst. The structure change of MoS2-MoO2 was confirmed by Raman and XRD analysis, and the MoS2 to MoO2 ratio was evaluated by XPS analysis. The hydrogen evolution reaction was conducted in 0.5 M H2SO4. The optimum MoS2 to MoO2 ratio increased the current density by increasing the active area of electrode. Further, we confirmed the decrease of electrical resistance as compared to carbon cloth only electrode. This research was supported by the Nano·Material Technology Development Programthrough the National Research Foundation of Korea (NRF), funded by the Ministry of Science and ICT (2016M3A7B4904328).

Resume : Metal nanoparticle doped graphene hydrogel has unique porous and 3D-networked structure. It has been received great attention because of their unique electronic and catalytic properties, large surface, and the synergistic properties resulted from the doped nanoparticles and graphene sheets as well 1-3. Herein, we prepared gold nanoparticle doped graphene hydrogel (AuNPs-GH) under various temperature (100, 120, 140, 160 and 180 ?) using hydrothermal treatment. The AuNPs-GHs were characterized by XRD, SEM, TEM and XPS. Results showed that AuNPs-GH can be successfully prepared. Temperature showed great effect on the formation of AuNPs-GHs and the particle size of AuNPs. Afterwards, a sensitivity amperometric sensor for detection of indole-3-acetic acid (IAA) and salicylic acid (SA) has been fabricated on AuNPs-GH modified glassy carbon electrode. Under optimum conditions, the sensor exhibited linear response to IAA and SA in range of 0.8-108 ?M and 0.8-230 ?M, with detection limits (S/N = 3) of 0.6 ?M (IAA) and 0.75 ?M (SA). This sensor showed good sensitivity and stability that it can be applied in the detection of IAA and SA in unknown samples with satisfactory results. 1. J. Zhang, R. Li, Z. Li, J. Liu, Z. Gu and G. Wang, Nanoscale, 2014, 6, 5458-5466. 2. A. M. Yu, Z. J. Liang, J. H. Cho and F. Caruso, Nano Letters, 2003, 3, 1203-1207. 3. Q. Zhu, J. Bao, D. Huo, M. Yang, C. Hou, J. Guo, M. Chen, H. Fa, X. Luo and Y. Ma, Sensors & Actuators B Chemical, 2017, 238, 1316-1323.

Resume : Early detection is proven to be the best chance for successful gynecological diseases and abortion treatment. Progesterone (P4), as ideal biomarkers, can identify abnormalities in the shortest time. Therefore, development of highly sensitive and easy operation methods for p4 is particularly critical. Here we report on a new disposable electrochemical sensor is a screen-printed reduced graphene oxide (RGO) electrode modified by 5-Amino-2-mercaptobenzimidazole (AMBI) and gold nanoparticles (AUNPS) to facilitate rapid detection of P4 levels, which has high bioaffinity for biological metabolites and greatly improves the sensitivity and accuracy of the electrode surface. Characterization was performed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and infrared spectroscopy (FT-IR). The properties of the resulting sensor were examined by cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). Under the optimum conditions of synergistic effects of various materials, the electrochemical reduction performance of P4 was greatly promoted when using square wave voltammetry (SWV) to determine P4.For the first time, AMBI have been applied for high-performance p4 sensing, with potential for development in further electrochemical sensing applications. Keywords: Reduced graphene oxide 5-Amino-2-mercaptobenzimidazole Progesterone Electrochemical sensor

Resume : Salmonella has been considered as one of the most common aetiological agent of foodborne pathogens, which can cause several human foodborne diseases 1, 2. Herein, we prepared polypyrrole functionalized reduced graphene oxide (PPy-rGO) under a mild condition and fabricated an ultrasensitive electrochemical biosensor for detection of Salmonella InvA gene sequences on PPy-rGO modified interface. The sensitive detection was due to the amplified reduction signal of H2O2 by using horseradish peroxidase-streptavidin functionalized gold nanoparticles (HRP-SA-AuNPs) and the facilitating electron transfer from PPy-rGO. Under the optimal conditions, there was a good linear relationship between the reduction current of H2O2 and logarithmic of InvA gene concentration ranging from 0.1 fM to 0.1 nM with a low limit of detection (LOD) of 15.8 aM (S/N = 3). Furthermore, the biosensor can apply in InvA gene detection in real samples. Results showed that the electrochemical signals of H2O2 related to InvA gene in PCR products from Salmonella were in good linear relationship with Salmonella cell concentrations ranging from 9.6 to 9.6×104 CFU mL-1 with a LOD of 8.82 CFU mL-1. It also exhibited good regenerability that it maintained 91.6% of its original response after 3 times regeneration. Refences 1. Y. Ye, Y. Liu, S. He, X. Xu, et al. Sens. Actuators B-Chem. 272 (2018) 53?59. 2. X. Liu, Y.X. Hu, S. Zheng, Y. Liu, et al. Sens. Actuators B-Chem. 230 (2016) 191?198.

Resume : Heavily p-type boron-doped diamond (BDD) has been utilized extensively as promising electrode material for supercapacitor applications, including electrical double layer capacitors (EDLCs) and pseudocapacitors (PCs). However, as another kind of conductive diamond, the electrochemical properties and applications of n-type doped diamond using for example phosphorus as the dopant have been rarely investigated. In this presentation, heavily phosphorus-doped diamond (P-NCD) was prepared with plasma enhanced chemical vapor deposition technique, and utilized for the first time as electrode material for the construction of EDLCs and PCs. By using the as-grown P-NCD as capacitor electrode, the related EDLC exhibits a capacitance of 11.40 ?F cm?2 in 1.0 M Na2SO4 aqueous solution at a scan rate of 10 mV s-1, while a semi-conducting behavior has been observed in redox-active electrolyte of 0.05 M Fe(CN)63-/4- + 1.0 M Na2SO4. Through a thermal post-treatment of these as-grown P-NCD films at high temperature in vacuum, the capacitances of EDLC and PC have been improved to be 2.01 mF cm-2 (at 10 mV s-1 in 1.0 M Na2SO4) and 63.56 mF cm-2 (at 20 mV s-1 in 0.05 M Fe(CN)63-/4- + 1.0 M Na2SO4), respectively. The variations of the properties, such as the surface morphology, surface chemical states, and conductivity, etc., of P-NCD films before and after annealing treatment have been studied by using different techniques like SEM, XPS, EIS, etc. The possible reasons regarding to the improved capacitances were discussed. The performance of P-NCD based supercapacitors was compared with those of BDD based supercapacitors, indicating that P-NCD is also a promising candidate for supercapacitor applications.

Resume : In recent years, core?shell structured nanomaterials with tunable functional properties have found their significance in various emerging applications including catalysis, adsorption, energy storage, sensing, etc.,Among them, the noble metal nanoparticles@metal?organic frameworks (NPs@MOFs) have recently received increasing attention due to the combination of electrical and catalytic properties of nanometals with the large internal surface area, tunable crystal porosity and unique chemical properties of MOFs. Furthermore, graphene oxide (GO) have also been developed to increase the electronic conductivity and hydrophilicity of ohter materials. As the derivative of graphene, it has large specific surface area, good suspension stability and a large number of edge sites, which can produce many electrochemically active sites for electron transfer during voltammetric measurements. Here, we explored the use of PVP?Au nanorods as nucleation seeds for zeolitic imidazolate framework?8 (ZIF?8) to synthesize AuNRs@ZIF?8 multi?core?shell structure by epitaxial growth or coalescence of nuclei. Subsequently, the AuNRs@ZIF?8 was assembled on GO nanosheets, which enables the core?shell structure to possess exceptional stability, superior electrical conductivity, eminent selectivity, and template effects. On this basis, a sensitive and stable electrochemical sensor was constructed for the detection of four pesticides including niclosamide, dichlorophen, carbendazim, and diuron. This nanocomposite holds great promise as catalysts for electrochemical sensor fabrication in terms of abundant multiple active sites, enhanced catalytic activity and remarkable stability.

Resume : We have developed an electrochemical device to evaluate deuterium concentration in aqueous samples. The sensitive material is based on palladium-functionalized carbon nanotubes (CNTs). Among custom metals, Pd shows the highest affinity towards hydrogen molecules [1] and CNTs are widely exploited in sensors and actuators [2]. Commercially available CNTs have been functionalized with 8-10 nm Pd nanoparticles using a micelle solution. The normal micelles were obtained from a microemulsion consisting of a mixture of ultrapure water, cyclohexane, isopropyl alcohol and a surfactant (Tween 20). Synthesis of the carbon nanocomposite was achieved through hydrazine reduction of Pd ions from the precursor. The morpho-structural properties of the carbon nanocomposite were investigated using TEM, EDX, SEM and Raman spectroscopy. TEM measurements confirmed the nano range of the Pd particles and showed the heterogeneous functionalization of the carbon nanotubes (Pd nanoparticles ?preferred? the hydroxylated positions onto the CNTs) [3]. The sensitive material was deposited onto a glassy carbon electrode and also on several screen-printed electrodes in order to perform electrochemical characterization and investigate the sensing behavior towards the analyte (2H) in a series of deuterium-enriched solutions ranging from 25 to 10.000 ppm. Dynamic impedance measurements were also performed to evaluate the interfacial electron transfer kinetics. The cyclic voltammetry has revealed a quasi-reversible behavior, with the oxidation peak having a lower intensity than the reduction peak. The analytical response of the composite to deuterium is given by the linear regression equation Ipc = 0.0042[D] + 38.7614, with R2 = 0.9237. Acknowledgments: Core Program PN-2019-OPTRONICA VI; Institutional Performance Programme-2019 [1] Ionete, E.I., et al., IEEE Sensors Applications Symposium, 2017. [2] M.Trefilov, A.Tiliakos, et al., Intl. J. Hydrogen Energy 42(15), 10448-10454, 2017. [3] L. Chen, H. Xie, W. Yu, pg. 213?232, chapter 9 in Carbon Nanotubes Applications on Electron Devices, Jose Mauricio Marulanda (Ed.), InTech, 2011.

Resume : Cu-TCPP/Graphene nanaosheets-based electrochemical sensing platform for rapid and simple determination of 5-Hydroxytryptamine Peng Hu, Liudi Ji* Hubei Collaboration Innovative Center for Nonpower Nuclear Technology, Hubei University of Science and Technology, Xianning 437100, China First author. E-mail: andy19860802@163.com * Corresponding author. E-mail address: jiliudi@126.com Metal-organic frameworks (MOFs), as a newly-developing multifunctional porous materials, has been widely used in many fields due to their unique advantages, such as large surface area, tunable morphology and pore size, varied structures and unsaturated coordination sites. However, reported MOFs systems to date still suffer from low mass permeability, poor conductivity and blockage of active metal centres by organic ligands, dramatically limiting their application in electrochemical sensor. Two-dimensional (2D) MOFs could be an effective strategy to acquire MOFs-based high-performance electrochemical sensors because the nanometre thicknesses to allow rapid mass transport, superior electron transfer and extremely high percentages of exposed catalytic active surfaces. Here, we used sonication exfoliation method to prepare Cu-TCPP (TCPP = etrakis (4-carboxyphenyl) porphyrin) nanosheets, then mixed with the exfoliation graphene to improve the conductivity and stability of Cu-TCPP nanosheets (Cu-TCPP/Graphene). Through X-ray diffraction, it can be found that Cu-TCPP/Graphene has been successfully prepared. The electrochemical sensing properties of the resulting compound was then studied using 5-Hydroxytryptamine (5-HT). It was found that the oxidation current of 5-HT on Cu-TCPP/Graphene modified GCE was highly increased, compared with GCE, Cu-TCPP/GCE and Graphene/GCE, owing to the synergistic effect of Cu-TCPP/Graphene. As a result, a new and highly sensitive electrochemical sensing plaform for 5-HT could be developed using Cu-TCPP/Graphene as the sensitive film.

Resume : Amorphous carbon, graphite, and diamond are three traditional members of the carbon family.[1] Depending on how the carbon atoms are arranged, carbon materials (e.g.,graphite, diamond) exhibit completely different properties. The recent addition of carbon nanomaterials, including CNTs and graphene, makes carbon family more diverse in the structure?property relationship, as the properties of CNTs and graphene vary with their sizes and structure symmetries even though they contain the same graphitic network at the molecular level.Having conjugated all-carbon structure with unusual molecular symmetries, CNTs and graphene possess interesting electronic,photonic, magnetic, electrocatalytic, thermal, and mechanical properties.[2] Doping carbon nanomaterials with heteroatoms(e.g., nitrogen, boron, phosphorus) can further cause electron modulation to tune their optoelectronic properties and/or chemical activities.These structure and property diversities make carbon materials, including carbon nanomaterials, attractive for a wide range of potential applications, including various key reactions involved in energy conversion and storage processes. The cathodic ORR is the key step in various sustainable and effcient energy conversion and storage techniques, including fuel cells and metal?air batteries. In this work, we report a spontaneous gas-foaming method to prepare nitrogen doped ultrathin carbon nanosheets (NCNs) by simply pyrolysing the mixture of citric acid and NH4Cl. NCN@GO gel-like hybrid is obtained by assembling intentionally exfoliated NCN sheets on graphene oxide(GO) sheets under a hydrothermal condition. Under the optimized pyrolysis temperature and mass ratio of precursors, the synthesized sample possesses ultrathin sheet structure, ultrahigh specific surface area, and rich edge defects, and exhibits low overpotential and robust stability for ORR.[3] References [1]Su D S , Perathoner S , Centi G . Nanocarbons for the development of advanced catalysts.[J]. Chemical Reviews, 2013, 113(8):5782-5816. [2]Wu Q , Yang L , Wang X , et al. From Carbon-Based Nanotubes to Nanocages for Advanced Energy Conversion and Storage[J]. Acc Chem Res, 2017, 50(2):435-444. [3]Jiang H , Gu J , Zheng X , et al. Defect-rich and ultrathin N doped carbon nanosheets as advanced trifunctional metal-free electrocatalysts for the ORR, OER and HER[J]. Energy & Environmental Science.

Resume : Clean and renewable energy technologies, such as fuel cells,batteries, water splitting, and carbon/nitrogen fxation, hold great promise toward solving current energy and environmental challenges[1].carbon-based materials have attracted considerable interest in many energy-related applications due to their abundance, chemical and thermal stability. A signifcant development in the design of g-C3N4 which features a stable structure with high nitrogen content and ample active sites for electrocatalysis and supercpacitor.In this work,we prepared g-C3N4 by thermal decomposition of urea which be used in supercapacitor and oxygen evolution reaction(OER) and have better electrochemical properties by the text. Firstly,in the positive material of supercapacitor. The unique g-C3N4 nanosheet electrode acquires high specifc capacity (600 F g?1 at 1 A g?1) and in the oxygen evolution reaction that exhibited low overpotential of 300 mV at the current density of 10 mA cm-2. After preliminary electrochemical testing , we can determinely that can be a good electrode material and catalyst In summary,the performance is attributed to the large surface area of C3N4 nanosheets not only served as a promising bridge for the integration of well-dispersed active materials but also delivered the composite structures with carbon- and nitrogen-rich active sites[2].So in the next work,we will prepare the carbon composites that can be used in many fields. [1] Sun M, Yan Q, Yan T, et al. Facile fabrication of 3D flower-like heterostructured g-C3N4/SnS2 composite with efficient photocatalytic activity under visible light[J]. Rsc Advances, 2014, 4(59):31019-31027. [2] Chen X , Liu Q , Wu Q , et al. Incorporating Graphitic Carbon Nitride (g-C\r, 3\r, N\r, 4\r, ) Quantum Dots into Bulk-Heterojunction Polymer Solar Cells Leads to Efficiency Enhancement[J]. Advanced Functional Materials, 2016, 26(11):1719-1728.

Resume : Micrometer scale polycrystalline born-doped diamond films were deposited on anodic aluminum oxide template with heat filament chemical vapor deposition (HFCVD). The BBD films with a surface of nano-array were obtained, which was characterized by SEM, TEM, AFM, XPS and Raman. The electrochemical properties, such as voltammetry curves were obtained under different scan velocity, to probe into the diffusion regime under standard seawater. The relationship between sensing properties and geometrical parameters of such BDD electrode was discussed.

Resume : With the rapid development of the world industrial economy, the search for efficient, cheap and green new energy has become the common goal of the majority of chemical researchers. Electrochemistry, as a science of mutual conversion of chemical energy and electrical energy, has received extensive attention. Traditional high-efficiency electrocatalysts are mainly concentrated on some scarce and expensive precious metal materials, so finding alternatives is a major challenge. As a new nanomaterial in the new century, carbon nanomaterials have excellent and unique physical, chemical and electronic conduction properties, so researchers have tried to apply it to the field of electrocatalysis. The sp2 hybrid carbon material has abundant free-moving ?-electrons, which makes it have certain application value in the reaction of electrons [1]. However, the undoped modified carbon material is in an electrically neutral state, and the inertness of these electrons makes it impossible to directly apply to the carbon dioxide reduction reaction. The capture of carbon dioxide by the catalyst depends on the defect sites of the catalyst itself. When a hetero atom such as oxygen (O), nitrogen (N), boron (B), phosphorus (P), sulfur (S), and iodine (I) is introduced into the carbon nanostructure, the carbon atom and these heteroatoms There are differences in atomic size and valence electrons, resulting in defects between adjacent carbon atoms, resulting in uneven charge distribution, destroying the electrical neutrality of carbon materials, and promoting the formation of CO2 adsorption and reduction active sites [2]. The current density of S, NCS (sulfur, nitrogen-nanocarbon) used in the electrocatalytic reduction of carbon dioxide to form formic acid is 25mA/cm-2.References [1]Gong J , Zhang L , Zhao Z J . Nanostructured Materials for Heterogeneous Electrocatalytic CO2 Reduction and Related Reaction Mechanisms[J]. Angewandte Chemie International Edition, 2017. [2]Lu L, Sun X, Ma J, et al. Selective electroreduction of carbon dioxide to formic acid on electrodeposited SnO_2@N-doped porous carbon catalysts[J]. Science China Chemistry, 2018(2):1-8.

Resume : In situ synthesis of Cu-BTC@ball-milled graphene composite and its electrochemical sensing properties Caoling Li, Xiaoyu Li, Kangbing Wu* Key Laboratory for Material Chemistry of Energy Conversion and Storage, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China First author. E-mail: caoling_li@hust.edu.cn * Corresponding author. E-mail address: kbwu@mail.hust.edu.cn Metal-organic frameworks (MOFs) have recently attracted considerable attention in the bio/chemical sensing for their large surface area, structure tunability and high porosity. However, the poor conductivity and stability of MOFs restrict their electrochemical application. According to recent researches, combination of MOFs with graphene to form a composite is a useful strategy to overcome this difficulty. Here, a simple and in situ method is developed to synthesize Cu-BTC(benzenetricarboxylic acid)@ball-milled graphene composite for electrochemical sensing. The morphology and structure of the obtained composite was comprehensive characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, Fourier transform infrared and Raman spectroscopies, X-ray photoelectron spectroscopy and nitrogen adsorption?desorption analyses. It was found that the composite of Cu-BTC@ball-milled graphene nanosheets was in situ synthesized using graphene as the support and regulator, Cu-BTC with nano-size loaded on the surface of ball-milled graphene nanosheets. Meanwhile, electrochemical properties including electrochemical catalytic, electrochemical adsorption capacity and reactivity were also studied. The results revealed that the combination of Cu-BTC and graphene can integrate the advantages, enabling the composite to possess improved stability, enhanced conductivity and increscent adsorption capacity. Owing to the synergistic effect of Cu-BTC@ball-milled graphene, the composite exhibits good electrochemical sensitivity towards various small organic molecules. Based on the Cu-BTC@ball-milled graphene composite, a series of sensing platforms were constructed to detect phenolic pollutants including bisphenol A and chlorophenol, and small biological molecules including xanthine and hypoxanthine. This new sensing system was used in real samples, and the results consisted with the values that obtained by high-performance liquid chromatography.

Resume : A new temperature-controlled electrochemical sensor for acetaminophen was first constructed. It consists of a triblock temperature-sensitive copolymer (type PS-PNIPAm-PS) and carbon nanocomposites (carbon nanotubes and graphene quantum dots). The electrochemical sensor exhibits different electrochemical behaviors at different temperatures. At low temperatures (less than 24 °C), the polymer on the glassy carbon electrode is stretched, the distance between the carbon nanocomposites is large, and the charge transfer resistance of the composite is also large. At this time, acetaminophen is almost impossible to exchange electrons on the electrode through the composite film, and exhibits the "closed" state. Conversely, at high temperatures (above 28 °C), the polymer is shrunk and acetaminophen is capable of undergoing a redox reaction on the electrode and is obtained to a redox current, exhibiting an "on" state. It is worth noting that this "on/off" state is sensitive and completely reversible. In addition, the sensor has a wide detection range (0.1 to 7.0 ?M and 7.0 to 103.0 ?M) and low LOD (66 nM) for acetaminophen. And the sensor exhibits excellent performance in the detection of actual samples (human serum and drugs). This switch sensor provides a novel idea for the combination and application of carbon nanomaterials and temperature-sensitive polymers.

Resume : We show that a stacking defect or a shift has a striking effect on carrier transport of bilayer graphene. Charge transport through a ballistic n?neutral?n junction of shifted bilayer graphene may result in minimal conductivity and shot noise anomalies which are found to be sensitive to the shift defect. Minimum conductivity and shot noise in shifted bilayer graphene exhibit an anisotropic beahavior as a function of the orientation of the electrodes. The minimum conductivity could be suppressed for somme specific value of twist defect while the shot noise takes the unit value. Our results provide a way to control transport properties in an undoped graphene bilayer structure by adjusting the layer stacking.

Resume : Copper is not only the one of the superior electrically conductive material, but also earth abundant metal. But copper is not used for the water electrolysis? electrodes in extreme electrolytes because of its weak corrosion resistance. For improvement of anticorrosion in extreme conditions, carbon coating and alloy is widely used. In this work, Ni-Cu alloy with graphene and carbon film was prepared via effective methods and evaluated for improving the HER performance. The role of carbon black film which exist between nickel and copper is to prevent the nickel and copper diffusion and the role of graphene is to increase the stability and electrical conductivity. The specific proportion of nickel and copper alloy with graphene has high electro-catalytic (onset potential: ~210 mV, tafel slope: 62 mV/dec) characteristics compared with copper and the long term stability in 3 types of electrolytes (pH 0, 7 and 14) were confirmed for 12hours respectively. This research was supported by the Nano?Material Technology Development Programthrough the National Research Foundation of Korea (NRF), funded by the Ministry of Science and ICT (2016M3A7B4904328).

Resume : There is currently intense research on sulfur/carbon composite materials as positive electrodes for rechargeable batteries. Such composites are commonly prepared by ball milling or (melt/solution) impregnation to achieve intimate contact between both elements with the hope to improve battery performance. Herein, we report that sulfur shows an unexpected ?spillover effect" when in contact with porous carbon materials under ambient conditions. When sulfur and porous carbon are gently mixed in a 1:1 mass ratio, complete surface coverage takes place within just a few days along with the loss of the sulfur bulk properties (crystallinity, melting point, Raman signals). Sulfur spillover also occurs in the presence of a liquid phase. Consequences of this phenomenon are discussed by considering a sodium-sulfur cell with a solid electrolyte membrane. L. Medenbach and P. Adelhelm; Cell Concepts of Metal-Sulfur Batteries (Metal = Li, Na, K, Mg): Strategies for Using Sulfur in Energy Storage Applications, Top Curr Chem., 2017, doi: 10.1007/s41061-017-0168-x L. Medenbach, I. Escher, N. Köwitsch, M. Armbrüster, L. Zedler, B. Dietzek, P. Adelhelm, Angew. Chemie Int. Ed. 2018, doi: 10.1002/ange.201807295

Resume : Platinum (Pt) is the most effective catalyst to hydrogen evolution reaction (HER), but it is rare and expensive. Recently, control of size and shape of Pt has been actively studied to solve its high cost and scarcity of Pt. In this study, highly distributed Pt nano-particle immobilized nanocellulose-carbon nanotube (CNT) foam composite was synthesized as effective electro-catalytic material for economical HER. Nanocellulose is an appropriate support of catalyst due to its light weight, stability, easy processibility and variety of chemical moieties. We synthesized nanocellulose foam by freeze dry technique and modify with polyethylene imine (PEI) for Pt immobilization. The immobilized amount of Pt nanoparticle on nanocellulose foam was varied by changing PEI density on the foam. The highly porous nanocellulose foam improves the dispersion of Pt nanoparticle. Furthermore, the CNTs were easily decorated to the Pt-nanocellulose foam by simply immersing the composite foam in CNT suspension, thereby creating percolation for electrical conductivity. The synthesized Pt immobilized nanocellulose-CNT foam was evaluated HER activity. Higher loading amount of Pt and highly developed electrical pathway of CNT coated Pt-CNF foam results in excellent HER activity.

Resume : CeO2 nanomaterials have exhibited extensive applications due to their superior physical and chemical properties, especially their morphology-dependent catalytic activity has been paid close attention very recently. In this presentation, we will show one-step hydrothermal deposition of CeO2 nanomaterials featuring various morphologies (i.e. nanorod, nanopolyhedra and nanocube). To obtain these CeO2 nanomaterials with expected properties, they were further composited with graphene nano platelets (GNP) with aid of ultrasonication. The characterization of the morphology and chemical composition of the prepared composites will be elucidated by TEM, XRD, Raman, and electrochemical techniques. Their applications towards electrocatalytic oxidation of tetrabromobisphenol A (TBBPA) will be shown. The electrocatalytic properties for the oxidation of TBBPA of these composites follow the order of CeO2 nanocube/GNP< CeO2 nanopolyhedra/GNP< CeO2 nanorod/GNP. Based on the enhancement of electrocatalytic activity of CeO2 nanorod/GNP, a novel sensing system with high sensitivity has been developed for TBBPA for example, the limit of detection as low as 1.8 nM. This new sensing system was also used in real samples with convincing performance.

Resume : Carbon nanofibers (CNFs), are promising additives for composite materials dedicated for high-end applications. High surface area, electrical/thermal conductivity, and mechanical properties of CNFs enable the realization of reinforced composites, sensors, energy conversion and storage devices. Electrospinning and post thermochemical treatment, enables a controlled, repeatable and cost effective fabrication and functionalisation approach for CNFs. Surface activation with photocatalytic, piezoelectric or magnetic moieties enhances electronic, thermal, mass and stress transport properties of a composite, enriching CNFs applicability. Herein we present a 3-step fabrication route for the generation of CNFs decorated with magnetic Fe3O4 nanoparticles (NPs). The presented methodology employs Fe3O4 activated electrospun cellulose nanofibers as Fe3O4/CNF precursors. Fabrication process includes: (i) Electrospining of cellulose acetate fibers (CAFs), (ii) transformation of CAFs into cellulose fibers via base hydrolysis, (iii) in situ generation and anchoring of Fe3O4 NPs onto the cellulose fiber surfaces. The magnetic fibrous polymer nanocomposites were subsequently transformed into magnetic Fe3O4/CNF by carbonization. The final product and its precursors were characterized by SEM, TEM/EDX, XRD and FTIR. These materials could be exploited as electrodes in supercapacitor technologies, adsorbents in water remediation processes and as high surface area photocatalytic substrates.

Resume : Proton Exchange Membrane Fuel Cells (PEMFCs) have achieved impressive power density, but the sluggish Oxygen Reduction Reaction kinetics today requires cathodes based on platinum, a rare and expensive metal. As an alternative, Fe-N-C catalysts prepared via NH3 pyrolysis have shown promising initial activity in PEMFC, but their poor in operando stability is a major drawback. Moreover, the lack of understanding of this instability has hitherto impeded identifying rational approaches to solve this issue. In this work, we compare activity and stability of Ar- or NH3-pyrolyzed Fe-N-C model catalysts (comprising only FeNx sites), both in acid and alkaline electrolytes. Fe leaching was measured online by mass spectroscopy coupled with a flow cell. In acid, we identify for the first time a specific demetallation kinetics, being potential-dependent and 10 times faster for NH3- vs. Ar-pyrolyzed Fe-N-C. In contrast, in alkaline medium, the Fe dissolution rate is slow and comparable between the two catalysts. Thus, in alkaline electrolyte, the outstanding activity of NH3-treated Fe-N-C is combined with high stability, while in acid medium, an antagonism exists between high activity and high stability. To identify dissimilarities between FeNx sites in operando, we used X-ray absorption spectroscopy, at pH 1 and 13. The NH3-treated Fe-N-C catalyst was then tested in anion-exchange membrane fuel cell, reaching a power density of 1 W cm-2, state-of-art result for this class of catalysts.

Resume : A simple and efficient hydrothermal approach using resorcinol, melamine and a commercial carbon black as carbon precursors has been successfully developed using a sacrificial polymer for the controlled development of porosity. Iron acetate was used for the incorporation in the carbon matrix of non-noble metal active centers. Further annealing of the particles in N2/NH3 atmosphere allowed the formation of a well-developed graphitic structure suitable for electrode applications. Scanning Electron Microscopy (SEM) shows the development of porosity which progresses after the annealing process. X-ray Diffraction (XRD) and Photoelectron Spectroscopy (XPS) were employed to investigate bulk and surface chemistry. Characterization methods show that iron particles are encapsulated in the carbon phase, while nitrogenated precursor compounds result in the formation of pyridinic and pyrrolic N-sites at the carbon surface. Thus obtained microspheres were tested as electrocatalysis for the oxygen reduction reaction (ORR) in alkaline solution using voltammetry and Rotating Disc Electrode (RDE) methods.

Resume : The development of flexible wearable electrochemical oxygen sensors is attractive for on-site monitoring of oxygen-related processes for applications such as biomedical assays. However, there are two technique bottlenecks to achieve this goal, e.g., the creation of large gas/electrolyte/electrode three-phase interfaces and the employment of solid or non-volatile electrolytes. Herein, a template filtration method for the scalable fabrication of carbon nanotube-based and paper-like electrochemical oxygen sensors is reported. This method employs photosensitive stamps to produce PDMS patterned PVDF membranes, which are then used for the filtration fabrication of self-designed and AuPt nanoalloy-doped single-walled carbon nanotube (SWNT) electrode arrays with high conductivity and favorable electrochemical behaviors. Taking advantages of the nanoporous structure of the SWNT electrode array coated PVDF membrane, large gas/electrolyte/electrode three-phase interfaces can be created at the back side of the composite membrane when either acidic ionic liquid (IL) or moisture activable solid-state electrolytes are modified on the front side. The produced paper-like electrochemical oxygen sensor shows a sensitive and rapid response towards the electrochemical reduction of oxygen in gas phases along with a high humidity resistance, which can be used for the real-time monitoring of oxygen concentrations in human respiratory gases.

Resume : We investigate the electrochemical properties of lipid structures interacting with CVD grown graphene layers for applications in electrochemical biosensors targeting membrane proteins. Due to its unique electrical properties, namely ultra-high electron mobility, wide electrochemical potential window, and low charge-transfer resistance, graphene offers many advantages in the development of biosensors with enhanced direct electron transfer between the electrode surface and electroactive proteins. However, in biosensors for membrane proteins a major problem is the denaturation of such proteins outside their native environment, the lipid bilayer of biological membranes, and therefore suitable lipid architectures need to be established on the electrode surface. In this work, we analyze graphene layers that were grown through chemical vapour deposition and subsequently treated by mild oxidation to improve their biocompatibility and interaction with supported lipid bilayers. The CVD graphene layers are characterized using scanning electron microscopy, Raman spectroscopy, and surface wettability before and after surface treatments. Electrochemical impedance spectroscopy is used to study the interaction of the modified CVD graphene with liposomes of different size and composition and the formation of supported lipid bilayers.

Resume : Nanoporous CMK-5 carbon consists of periodically arranged, cylindrical tubes of amorphous carbon. The voids between adjacent tubes form a continuous system of pores (inter-tubular), whereas the interior of the hollow tubes constitute another mode of pores (intra-tubular). The two pore systems can be addressed independently during the synthesis of CMK-5 (by using porous SBA-15 silica as a structural scaffold). It is possible to load only one of the two pore systems with guest species or to modify/functionalize the pore walls. We present CMK-5 carbon with selective functionalization of the intra-tubular pores: (i) Oxygen-containing functionalities at the pore walls were created by oxidative treatment with acidic persulfate solution. This leads to increased polarity, as investigated by water vapor physisorption analysis. The other (inter-tubular) pore system remains nonpolar, resulting in a bifunctional material. (ii) The intra-tubular pores were also individually filled with elemental sulfur, yielding a porous sulfur/carbon composite with promising properties for application as a cathode in lithium-sulfur cells. Since the inter-tubular pores are still empty, a dual function emerges; one pore system hosts the guest species (sulfur), while the other pore system may be used for efficient electrolyte penetration. (iii) Likewise, we have created SnO2 nanoparticles in the intra-tubular pores for potential application as an anode material in Li-based cells. The materials are characterized by a variety of techniques, including N2 and H2O physisorption analysis, Hg intrusion porosimetry, electron microscopy, and low-angle X-ray diffraction, including an in-depth study by theoretical simulation of low-angle X-ray data.

Resume : The studies of the peculiarities of the interaction of C70 with NMP solvent by optical absorption, fluorescence and fluorescence excitation were performed. The results of experiments on the spectroscopy showed a sharp decrease in the optical density of absorption in the region of electronic transitions and a significant decrease in the fluorescence quantum yield of N-methyl-2-pyrrolidone when adding C70. These facts indicate the effective electron capture of solvent molecules by fullerenes. The line shape and position of fluorescence bands indicate the aggregation of C70 complexes with NMP depending on the storage time of solution.

Resume : Porous nanocarbons have been established as main materials in the manufacturing of microporous layer (MPL), a main component of PEM fuel cells (FC). MPL has the role of enhance the water/gas management and facilitate electron transfer, thus influencing both FC cost and performance. However, with low quality carbon, the corrosion of the carbon material leads to mass loss and low durability ? one of the main causes which hinders large scale implementation of low-temperature fuel cells. Obtaining high quality nanocarbons at competitive yield-to cost ratio constitutes an important objective, with plasma or pyrolytic techniques having shown promise for the bulk production of nanocarbons. We present the first results of using plasma-grown carbon nanowalls as MPL in PEM FCs. The carbon nanowalls were synthesized by Radiofrequency Plasma Enhanced Chemical Vapor Deposition and grown directly on carbon paper, thus forming a durable gas diffusion layer (GDL). The GDL-MEA is tested on a BT-112 Single Cell Test System, showing power performance comparable to industrial quality membrane assemblies, with elevated working potential and impeccable fuel crossover for a low-cost system resulting from a highly scalable, inexpensive, and rapid manufacturing method. Keywords: nanocarbon, plasma, nanowalls, electrochemical conversion, microporous layer, PEM fuel cell

Resume : A pure graphene oxide film (GOM), which is known to have hydrophilicity, mechanical strength and high proton conductivity, was used as an electrolyte for a hydrogen membrane fuel cell (HMFC). Typical hydrogen permeable membrane fuel cells (HMFCs) consist of a Pd membrane as a hydrogen permeable layer, a perovskite-structured oxide electrolyte and a cathode. However, proton conducting perovskite has a serious problem of low crystallinity, a difficult deposition process, and low chemical stability. Therefore, we have studied several alternatives to the electrolyte materials of conventional HMFCs. That is, a thin metal hydrogen permeable membrane such as Pd or Ni64Zr36 was deposited on a pure GOM to reduce the fuel gas leakage and reduce the reduction reaction of hydrogen and graphene oxide. The GO-HM double layered electrolyte membrane (GOHM) was prepared by dc-magnetron sputtering on the GOM from the aqueous solution by drop casting by adjusting its thickness to about 12 ?m. Furthermore, the HM of the GO-HM bilayer electrolyte membrane (GOHM) enables the realization of a Pt-free anode fuel cell by performing an anodic catalyst reaction on hydrogen gas. For the fabricated GOHMFC using conventional Pt/C electrodes showed a maximum power density of 21 mW/ cm2 at 60 °C when H2/O2 gases are used. However, GOMFC without alloy thin film showed that of 3 mW/ cm2 under same condition. Furthermore, GOHMFC without Pt/C anode (that is, Pt-free anode GOHMFC) showed maximum power densities of 10.55 mW/ cm2 and 4.65 mW/cm2 for GOHM(Pd)FC and GOHM(Ni64Zr36)FC, respectively.

Resume : MoS2 nanoplates and Born-doped diamond film on Mo substrates were fabricated with chemical vapor deposition method in the same vaccum system, Au nanoparticles (AuNPs) were deposited on the surface of MoS2, obtaining BDD/MoS2/AuNPs Composite Electrodes. Heavy metal ion single and mixed solutions(Hg?Cd?As?Cr) with different concentration were used to evaluate the performance of the prepared electrode. The electrode will combine the electrochemical performance of AuNPs-MoS2 in heavy metal ion detection and the stability of BDD electrode to detect trace heavy metal ions in harsh environment.

Resume : As an important biomarker for early cancer diagnostics, microRNA-21 (miRNA-21) has attracted extensive attentions concerning its accurate detection. By combination of the T7 exonuclease (Exo)-assisted target recycling and electrochemical signal promotion at a vertically aligned single-walled carbon nanotubes (SWCNTs) modified electrode, this work successful develops an ultrasensitive biosensing method for the one-step detection of miRNA-21. The biosensor is constructed based on the covalent linking of terminal carboxyl-activated SWCNTs and PEG molecules at a diazonium salt-modified electrode. The ?-? stacking interaction enables the specific binding of the ferrocene (Fc)-labeled single-stranded signal DNA onto the SWCNT surface, and the PEG embedding well resists the non-specific adsorption. Based on the DNA hybridization with the target miRNA-21, a DNA/RNA hybridized duplex forms and releases from the electrode surface, resulting in the electrochemical signal decrease of the Fc labels. With the assistance of catalytic digestion of the signal DNA strand in the DNA/RNA duplexes from its 5? to 3? terminus by T7 Exo, the miRNA-21 will release and participate the biorecognition reaction again. This target recycling strategy great enhances the signal response along with the electron transfer promotion of the SWCNTs modified on electrode. It results in the successful development of a novel biosensing method for the ultrasensitive and convenient detection of the miRNA-21 biomarker.

Resume : Pt nanoparticles supported on high surface area SiC (Pt/SiC) were synthesized using a versatile cyclic voltammtric deposition method. As the electrocatalyst for methanol oxidation, the catalyst has a high electrochemical active surface area (ECSA) of 110.8 m2g-1, which is higher than that of Pt nanoparticles supported on carbon nanotubes (Pt/CNTs) (75.4 m2g-1), and that of commercial Pt/C (76.2 m2g-1). A strong interaction between Pt and SiC is observed, which makes Pt/SiC catalyst high activity and excellent stability even at Pt loading as low as ~1.7wt%. In addition, Pt/SiC catalyst shows a higher ratio of the forward anodic peak current (If) to the reverse anodic peak current (Ib), and thus effectively alleviates CO poisoning effect to Pt nanoparticles. These results suggest that high surface area SiC could be a promising supporting material for methanol electro-oxidation catalyst.

Resume : Demand for high-energy density lithium secondary batteries is rapidly increasing in large energy storage applications such as electric vehicles and grid storage systems. To achieve a high-energy density battery (> 250 wh kg-1), it is essential to design a new negative electrode with high capacity and low working potential. Recently, lithium metal anodes have attracted more attention than graphite and silicon anode materials due to their high specific capacity (3860 mAh g-1) and low working potential (SHE vs. -3.04 V). However, due to dendrite growth and dead lithium formation, it is urgent to address the safety and capacity loss problems of lithium metal electrodes. Designing an optimal host structure can be the best way to solve this problem through reversible lithium deposition / stripping. It is expected that large surface area can reduce effective areal current density while voids or pores can reduce the reversible capacity. In the present study, the carbon host was designed to have a large surface area with a non-porous structure. Carbon nanotube grafted-carbon nanofibers were synthesized by electrospinning, heat treatment and chemical vapor deposition. The morphological and structural characteristics of these carbon nanofibers were fully characterized by SEM, TEM, XRD and Raman spectra. Improved electrochemical performance achieved using the optimal host will be discussed in detail at the conference.

Resume : Efficient electrocatalysts for oxygen evolution are vitally important for regenerative fuel cells and metal-air batteries. Herein, 3D mesoporous and ultrathin array of CoN nanosheets are synthesized on the Ni foam viathermal transformation of Co3O4 nanowire arrays. This array imparts enhanced active sites, mass diffusion, andelectron transfer towards oxygen evolution reaction. The low overpotential of 323 mV at 30 mA cm?2, a Tafelslope of 74 mV dec?1, and a high potential conservation in a long process of electrolysis process are achieved. It is thus one robust and efficient electrocatalyst for OER.

Resume : Growing a simple, rapid, and sensitive electrochemical immunosensor for monitoring carcinoembryonic antigen (CEA) is vital for early determination and diagnosis of cancer. Herein, reliable detection of CEA platform was constructed based on reduced graphene oxides (rGO) and ZnO nanocomposites (ZnO@rGO) by in situ reduction of GO with Zn powders, combined magnetic beads-capture antibody (MBs-Ab1) and detection antibody-gold-alkaline phosphatase bioconjugates (Ab2-AuNPs-ALP). Through an external ?sandwich? reaction, the MBs-based bioconjugates were modified on the renewable surface of carbon paste electrode and the magnified signal can be achieved as follows: the ALP hydrolysis of the inactive substrate 1-naphthyl phosphate (1-NPP) to in situ generate an electroactive product 1-naphthol (1-NP); Meanwhile, 1-NP could be catalytic oxidized by ZnO@rGO nanocomposites and the introducing of cetyltrimethylammonium bromide (CTAB) obviously enhances accumulation efficiency for 1-NP, resulted in the facilitation of electron transfer and amplification of electrochemical signal. The corresponding immunosensor, achieved good linear in the range of 0.01-6.0 ng mL-1 with the detection limit of 4 pg mL-1 (S/N =3), which was successfully implemented to the determination of CEA in serum samples from both healthy people and cancer patients (commonly, colorectal cancer, breast cancer, lung cancer, gastric cancer and pancreatic cancer). Hence, the current work established a universal signal amplification strategy for the design of exclusively selective, highly sensitive, and instant-convenient electrochemical biosensors.

Resume : Dye-sensitized solar cells (DSSCs) are regarded as prospective solar cells due to its acceptable energy conversion efficiency, low-cost and simple production.The counter electrode (CE) plays a crucial role collects electrons from the external circuit and reduces the tri-iodide to iodide species by converting tri-iodide generated at the anode back to iodide, which has a significant influence on the photovoltaic performance. [1] platinum (Pt) is normally used as the CE for reducing the I3? redox species,and cobalt(II/III) electrolyte and zinc porphyrin dye achieved a highest power conversion efficiency of 12%.[2]However,Pt is an expensive and scarce material. Therefore, it is highly desired to seek for sustainable alternative materials for platinum group metals.[3] 2D transition metal dichalcogenides (TMDs) analogous structure like graphite,it structure is composed of three atomic layers, a W layer sandwiched between two S layers, and the triple layers are stacked by weak van der Waals interaction.[4]Wu et al,used commercial WS2 as a CE material for DSSCs. They demonstrated that WS2 was a good candidate to replace a Pt CE in DSSCs.WS2 is undoubtedly a hopeful material for catalyzing the reduction of I3.[5]
Metal-organic framework (MOF) synthesized by the assembly of metal nodes and organic linkers, have emerged as promising materials for diverse applications due to their high porosity and ultrahigh surface area.[6]Calcinate the MOF material at high temperature,get the N-doped hollow carbon nanocages.TMDs combined with MOF templating synthesis of few-layered WS2 Nanoplates confined in Metal-organic framework Nanocaqes for dye-sensitized solar cells as the counter electrode.[7] References [1]Jihuai Wu, Zhang Lan, Jianming Lin, et al. Counter electrodes in dye-sensitized solar cells[J]. Chemical Society Reviews, 46(2017)5975-6023. [2]Yella A, Lee HW, Tsao HN, Yi CY, Chandiran AK, Nazeeruddin MK, et al. Porphyrin-sensitized solar cells with cobalt (II/III)- based redox electrolyte exceed 12 percent efficiency. Science 2011;334:629?34. [3]Z. Jin,M.Zhang,M.Wang,C.Feng,Z.-S.Wang,Metal selenides as efficient counter electrodes for dye-sensitized solar cells,Acc. Chem. Res. 50 (2017)895-904. [4]Tenne R, Margulis L, Genut M, Hodes G. Polyhedral and cylindrical structures of tungsten disulphide. Nature 1992;360:444?6. [5]Wu MX, Wang YD, Lin X, Yu N, Wang L, Wang L, et al.Economical and effective sulfide catalysts for dye-sensitized solar cells as counter electrodes. Phys Chem Chem Phys 2011;13:19298?301. [6]H. Furukawa, K.E. Cordova,M.O?Keeffe,O.M.Yaghi,Science 2013,341, 1230444. [7]Xu C , Zhang J , Qian X , et al. Template synthesis of cobalt molybdenum sulfide hollow nanoboxes as enhanced bifunctional Pt-free electrocatalysts for dye-sensitized solar cells and alkaline hydrogen evolution[J]. Electrochimica Acta, 2018, 289:448-458. Biography Yanfang Gao has completed her PhD at the age of 30 years from Fukui University and postdoctoral studies from Tsinghua University of Chemistry. She is a professor at the department of Inner Mongolia University of Technology,a tutor of a phD student.She has published more than 20 papers in reputed journals. Presenting author details Full name: Xiaofeng Li Contact number: +86 13081512254 Session name/ number: European Materials Research Society Category: Poster presentation

Resume : Currently, environmentally friendly and low-cost electrode materials are being sought to meet the urgent demand of sustainable electrochemical energy storage system. Chitin, as the second most abundant biopolymer, can be obtained easily from the shells of crustaceans such as shrimps, crabs, and insects. Herein, we use nitrogen-doped amorphous carbon nanofibers (NACF) synthesized by direct pyrolysis of chitin as the anode material in sodium-ion batteries (SIBs) and potassium ion batteries (KIBs). Benefiting from the multiple synergistic effects of heteroatom doping and one dimensional mesoporous structure, the SIBs and KIBs deliver the high reversible capacity, excellent rate capability and long-term cycling stability. Therefore, our work will inspire the further exploration of other natural carbonaceous materials to be applied in the development of the green energy storage system.

Resume : In the dye-sensitized solar cells, carbon-based materials have attracted considerable interest in many energy-related applications due to their abundance, chemical and thermal stability, and processability.[1] Among them, graphene nanosheets with two-dimensional sp2- hybridized carbon structure have been widely used as one of the carbon-based materials for replace the Pt counter electrode materials due to their excellent electrical conductivity and optical transmittance, large surface area, good mechanical strength and chemical stability.[2] From a development perspective, optimizing the catalytic performance of carbon materials is a key factor in improving the optical performance of the entire DSSC. Because the oxygen-containing functional groups in the graphene nanosheets destroy the carbon network structure, thereby reducing its conductivity.[3] The hetero atom such as nitrogen can cause structural deformation by local strain in the carbon skeleton to modify the graphene, thereby improving the catalytic activity without lowering the electrical conductivity of the graphene. Other heteroatoms can synergistically enhance the electrocatalytic activity of graphene nanosheets by asymmetry increasing the different charge and spin densities. Here, we prepared S and N double-doped graphene (SNG) catalysts by one-step method by selecting highly active S and N atoms as doping elements, and combined them with NiS2 as counter electrode materials. Double doped graphene sheets are expected to replace the expensive Pt counter electrode in DSSC. References [1] Liang J , Jiao Y , Jaroniec M , et al. Sulfur and nitrogen dual-doped mesoporous graphene electrocatalyst for oxygen reduction with synergistically enhanced performance[J]. Angewandte Chemie International Edition, 2012, 51(46):11640-11640. [2] Ahn H J , Kim I H , Yoon J C , et al. P-Doped three-dimensional graphene nano-networks superior to platinum as a counter electrode for dye-sensitized solar cells[J]. Chemical Communications, 2014, 50(19):2412-2415. [3] Kannan A G , Zhao J , Jo S G , et al. Nitrogen and sulfur co-doped graphene counter electrodes with synergistically enhanced performance for dye-sensitized solar cells[J]. Journal of Materials Chemistry A, 2014, 2(31):12232-12239.

Resume : The surrounding air may contain volatile organic compound (VOC) vapours which can be harmful to human health. In the last few decades, different sensor materials are being extensively researched for detection of different VOC vapours. One of the promising materials for the VOC vapour detection is a polymer and electro-conductive nanoparticle composite, which is suitable to function in room temperature. In this work ethylene vinyl acetate copolymer (EVA) with vinyl acetate content 40 % was used as a polymer matrix and graphitized carbon black nanoparticles Printex XE-2 with an average particle size of 30 nm were used as a filler. The Printex XE-2 is a high-conductivity carbon, which is widely used for electro-conductive elastomers. The carbon black nanoparticles were arranged in EVA matrix using both AC and DC electric fields during the composite solution vaporization process. As a result, arranged nanoparticle composite was obtained and its anisotropy of conductivity was measured. Anisotropy for both compositions, which were made using AC and DC electric fields, was found to be similar, 3.00 for the AC mode and 3.39 for the DC mode, respectively. Although the anisotropy of conductivity was similar, the sensing measurement results in toluene vapours were different. In the case when samples were made using the AC field, increased sensing abilities were found. In the case of the DC field, sensing abilities were not increased compared to unarranged sample.

Resume : Cotton is established as an innovative foundation for smart wearable energy storage devices with appealing properties. The challenge is that the current approaches using either additional coating or direct carbonization mostly lead to mechanically fragile or electrochemically poor fabric. We demonstrate that metal oxide coating on the cotton and subsequent pyrolysis allows metal atoms to migrate into the resulting carbonized-cotton with graphite-like layers, which brings about considerable changes in microstructure and porosity of the cotton. This process yields carbonized cotton with simultaneously increased material toughness and supercapacitive properties. Our result could be potentially a model case for more general approach to simultaneously enhance both mechanical and electrochemical performance of any other omnipresent carbon based materials.

Resume : Starbon® and its derivatives have been highlighted as inexpensive biomass-derived highly mesoporous carbonaceous materials. Its production process, which consists in a direct thermal transformation of various polysaccharides without any template, greatly satisfies the main sustainability terms such as simplicity, cost effectiveness and most importantly, eco-friendliness. Recently, in the frame of the POROUS4APP project, we have shown the strong potential of Starbons® for the green synthesis and formulation of Li-ion battery electrodes. In a first approach, Starbons® were employed as highly efficient carbon additives for both negative (LTO) and positive Li-ion electrodes, even surpassing conventional carbon black additives (e.g. Super P). A synergistic effect was observed for a binary carbon additive system composed of Starbon® with Super P, improving both the initial capacity and the rate capability of LMO and NMC positive electrodes. In a second approach, alginic acid-derived Starbons® were employed as template for the synthesis of LTO/C and LMO/C nanocomposites. The presence of homogenously grafted and/or coated carbonaceous species around metal oxide nanoparticles has been demonstrated to ensure better electronical interconnection between particles. In this communication, we will present and discuss our latest results regarding the use of Starbon® materials as carbon additives and/or templates for the synthesis and formulation of Li-ion battery electrodes.

Resume : The functionalization of graphene with the preservation of the basal plane structure is essential for developing graphene-based materials. Usually, the functionalization of graphene is carried out by a combination of the pre-oxidation and exfoliation of graphite into graphene oxide (GO) and the post-reduction of GO into reduced GO (RGO). However, the as-prepared RGO exhibite poor electrochemical performance due to partial reduction of the defects. Selective functionalization at the edge of graphene can minimize the damage in the basal plane to receive much attention. We developed a method to the preparation of edge-selectively hydroxylated graphene nanosheets (EHGs) during the ball milling of graphite in the presence of persulfate as the co-milling agent. The as-prepared EHGs possess less basal-plane defects to show higher conductivity than previously reported EHGs by approximately 1 ~ 4 orders of magnitude.

Resume : Unique structure of graphene makes it possible to tune its properties via chemical functionalization. Doping heteroatoms into the structure of graphene is one of the main strategies in functionalization, nitrogen doping of graphene not only can alter its electronic properties, but also it can create sites that are electrochemically active. This makes N-doped graphene one of the best non-metallic candidates to replace Pt catalysts. Different C-N bonding configurations in these structures as well as the concentration of N atoms in the structure of graphene are crucial factors in potential applications of functionalized graphene as a fuel cell cathode for Oxygen Reduction Reaction (ORR). Despite significant improvements in the synthesis of N-doped graphene, there are still unsolved questions regarding the control of these factors in its honeycomb network. Here, we report synthesis of large area homogeneously doped graphene films. A cross-examination of core level spectroscopy and Raman spectroscopy findings as well as electronic structure mapping results are used to investigate about configuration of N atoms in samples with different dopant concentrations. It has found that the N amount is graphene thicknesses dependent while its configuration can be manipulated by heat treatment at mild temperatures. Rotating disc electrode measurements revealed that pyridinic and nitrilic N groups, which are dominant after heat treatment, have higher electrochemical activity in ORR compared to other N configurations.

Resume : Porous carbons have been extensively studied in supercapacitors. However, it remains a grand challenge for porous carbons to achieve a volumetric capacitance (Cv) of over 200 F cm-3 because of the low intrinsic density and limited capacitance. Herein, we propose a pomegranate-like carbon microsphere (PCS) constructed by monodisperse, submicron, N-doped microporous carbon spheres for high-volumetric-capacitance supercapacitors. The assembly of submicron carbon spheres into pomegranate-like structures significantly reduces the required binder amount (2.0 wt %) for electrode preparation, diminishes the interparticle resistance, and most importantly, endows the PCS with a high packing density (0.75 g cm-3). Benefited from the high surface area (1477 m2 g-1), N doping (3.0 wt. %), and high packing density, the PCS demonstrates a high Cv (254 F cm-3), four times that of unassembled monodisperse carbon spheres. This work opens a new avenue to enhance the Cv of porous carbons without compromising the rate capability or cyclability.

Resume : Nowadays lithium-ion supercapatteries by virtue of a higher energy density and longer cycle life by the electrical and electronic industry wide attention. Because lithium-ion supercapatteries special assembly method[1], it combines the lithium-ion battery and supercapacitor energy storage advantages. However lithium-ion supercapatteries still face many challenges, such as poor rate capability and lower power desity[2]. Lithium vanadium phosphate (Li3V2(PO4)3) is the one of has great potential in the future Electrode material[3]. In this work, we find that Li3V2(PO4)3 is the three-dimensional (3D) network, because of this special structure will make the phase body space of Li3V2(PO4)3 expand, reduce the resistance of the intercalation/de-intercalation of cations (e.g. Li+) in the bulk of active materials. However the phosphate family has been known to have poor lithium-ion diffusion coefficient[3]. We used a surfactant as a carbon source to prepare mesoporous nanosheets ordered structure using the modified sol-gel method. This composite electrode material has a very high specific capacity (166 mAh g-1) and a good rate performance (a specific capacity of 90 mAh g-1 at 20 C). With activated carbon as the negative electrode were assembled into lithium-ion supercapattery, the lithium-ion supercapattery delivers a discharge time of as long as 1369.24 s, a maximum energy density of 53.22 Wh kg-1 and a maximum power density of 3.01 kW kg-1. Such lithium-ion supercapatteries thus overcome the disadvantages of rapid energy density attenuation under high power density of existed lithium-ion supercapatteries. Reference [1] Sun F, Gao J, Zhu Y, et al. A high performance lithium ion capacitor achieved by the integration of a Sn-C anode and a biomass-derived microporous activated carbon cathode[J]. Scientific Reports, 2017, 7. [2] Ma Y, Chang H, Zhang M, et al. Graphene?Based Materials for Lithium?Ion Hybrid Supercapacitors[J]. Advanced Materials, 2015, 27(36): 5296-5308. [3] Rui X, Yan Q, Skyllas-Kazacos M, et al. Li3V2(PO4)3 cathode materials for lithium-ion batteries: a review[J]. Journal of Power Sources, 2014, 258: 19-38.

Resume : Recently, N-doped carbon materials have attracted much attention as a promising material because they could function as effective electrocatalysts for oxygen reduction reaction (ORR) which is a critical process in the energy conversion devices. The N-doped carbon materials have been synthesized by a combination process of CVD and thermal treatment under specific conditions. Solution plasma, which is a discharge in the liquid phase, also has the potential for a simple and easy synthesis of the N-doped carbon materials in liquid phase. In this presentation, we report synthesis of the N-doped carbon materials and estimation of the electrocatalytic activity for ORR of the carbon materials. The discharge system consisted of two wire-type metal electrodes placed in a glass vessel and driven by a bipolar DC pulse power supply. The pulse frequency and pulse width employed were 30 kHz and 2 µs, respectively. Benzene was used as solvent for all experiments. Pyrazine was used as a raw material to synthesize the nitrogen-containing carbon materials. The electrocatalytic activity for ORR of the synthesized sample was investigated in 0.1 M KOH solution by electrochemical measurements using rotating disk electrode (RDE). TEM-EDX revealed that the sample synthesized from pyrazine was composed of carbon and nitrogen. Cyclic voltammetric curve for the N-doped carbon materials synthesized by solution plasma showed that the reduction current density for ORR increased and the onset potential for ORR shifted to positive direction compared to those of carbon sample without nitrogen.

Resume : Electrical double layer capacitor (EDLC) is an important electrochemical energy storage device for its ultrahigh power density. Short in energy density, improving its capacity under fast charging has been a long-standing challenge. [1] While researchers have achieved superior capacity (> 200 F/g) under high current density (> 10 A/g) through rational porosity design on hierarchical porous activated carbon, [2] the connection sequence of multiscale pores, which shall be important and greatly editable, remains unattached. [3] Appropriate design of the interconnection of multiscale pores shall bring the performance of EDLC to a new height. In this work, we employed SiO2 templating method and KOH activation to fabricate hierarchically interconnected macro-meso-micro pores on chitosan aerogel based activated carbon, and used it as active materials for EDLC. The preliminary energy storage performance has showed superior rate capability of our product to those control samples with similar porosity but random pore connection, as well as commercial activated carbons. The improved power density is primarily ascribed to the enhancement of ion diffusion and easing of ion desolvation by the hierarchical interconnection of the multiscale pores. This work reveals the influences of pore size sequence to EDLC performance, and show guidance to future EDLC active material design. [1] Lee, J. A.; Shin, M. K.; Kim, S. H.; Cho, H. U.; Spinks, G. M.; Wallace, G. G.; Lima, M. D.; Lepro, X.; Kozlov, M. E.; Baughman, R. H.; Kim, S. J. Nat. Commun. 2013, 4, 1970 [2] Zhang, F.; Liu, T.; Li, M.; Yu, M.; Luo, Y.; Tong, Y.; Li, Y. Nano Letters 2017, 17, 3097 [3] Péan, C.; Merlet, C.; Rotenberg, B.; Madden, P.; Taberna, P.; Daffos, B.; Salanne, M.; Simon, P. ACS Nano 2014, 8, 1576

Resume : Transition metal disulfides, such as MoS2, possess layered structure analogous to graphite and have been widely applied in the fields of catalysis, transistors, hydrogen storage, solid lubricants, Li-ion batteries, and double-layer capacitors. Bulk MoS2 crystal has been demonstrated a semiconductor with the indirect bandgap of ~ 1.2 eV. As being exfoliated to form monolayer or a few-layer MoS2 nanosheets, it will be transformed to be a semiconductor with direct bandgap of ~1.8 eV. Thus, it will be an excellent photoactive material for photoelectrochemical sensing platform. However, the low photoelectric conversion efficiency often limits its photocurrent response, thus further limits the sensing performances of the prepared photoelectochemical sensors. Therefore, to incorporate conductor into MoS2 nanosheets to promote the photogenerated electron-hole pairs separation, thus to enhance the photocurrent response is a facile and efficient strategy. Herein, using cetyltrimethyl ammonium bromide (CTAB) as morphology control reagent and ammonium molybdate as molybdenum source, ultrathin-layered carbon intercalated MoS2 hollow nanospheres (C/MoS2) were prepared by a hydrothermal method coupled with high temperature annealing. Gold nanoparticles were integrated onto C/MoS2 surface through in-situ reduction of chloroauric acid without adding any reductant to produce an AuNPs/C/MoS2 nanocomposite. The as-prepared AuNPs/C/MoS2 nanocomposite was confirmed by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). Then, AuNPs/C/MoS2 nanocomposite was coated onto a glassy carbon electrode surface as a photosensing platform for immobilizing pro-gastrin releasing peptide antibody (anti-Pro-GRP) to fabricate an immunosensor for Pro-GRP. Experimental conditions for Pro-GRP determination were optimized. A sensitive, selective and accurate method has been developed for Pro-GRP assay.

Resume : Graphene quantum dots can be regarded as graphene with a lateral dimension of less than 100 nm. In contrast, graphene quantum dots not only have the excellent properties of graphene, but also have been proven to have better biocompatibility, low toxicity, high fluorescence stability and strong water solubility. We used sodium hydroxide and citric acid as raw materials, functionalized with binaphthol derivatives, and hydrothermally prepared a graphene quantum dot modified by binaphthol derivatives. The graphene quantum dots have blue fluorescence, stable state, good reducibility and high quantum yield. Comparing the N-doped graphene quantum dots without the binaphthyl groups prepared by the same method, the functionalized quantum dots of the binaphthol derivative exhibit strong responsiveness to Hg2+ in the phosphate buffer solution and the DNA solution. The phosphate buffer has the effect of adjusting the pH, and the complete, active substance can ensure that it participates in the biological reaction under the optimal conditions. The graphene quantum dots we prepared have strong responsiveness to Hg2+ in this environment. The results of this study provide a valuable reference for the application of graphene quantum dots in biological environments and the functional design of graphene quantum dots.

Resume : Abstract In this work, the niobium oxide and nitrogen-doped iron carbide nanotubes (Nb2O5-Fe3C@NCNTs) composites was successfully synthesized. The phase structure, morphology and component were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The XPS results implied that the valence state of iron was main Fe2+ and Fe3+ forms in Fe3C@NCNTs and Nb2O5-Fe3C@NCNTs samples. The electrocatalytic activity of the Nb2O5-Fe3C@NCNTs composites was performed in a 0.5 M KOH solution containing 1 M methanol and ethanol, respectively. The results implied that Nb2O5-Fe3C@NCNTs had good electrocatalytic activity toward methanol and ethanol oxidation in alkaline medium. 1. Introduction The use of fossil fuel comes serious environmental emission and human health problems. Fuel cells are considered to be the clean energy sources in 21st century. Direct alcohol fuel cells (DAFCs) have been attractive increasing due to their advantages (for example, high energy density, easy storage and facile transport) [1,2]. However, the commercialization of they has been limited because of use of high cost Pt-based catalysts toward alcohol oxidation. The metal oxides have been often served as electrode materials due to their specific catalytic and conduction. For example, Zhou et al. studied that Pt/CeO2 nanoparticles exhibited high electrocatalytic activity toward the oxidation of methanol in acid medium [3]. The Pd-NiO/MWCNTs supported on reduced graphene oxide electrocatalyst exhibit high catalytic activity for ethanol oxidation in alkaline medium [4]. Nb2O5 is a kind of stable metal-oxide in usual acid and alkaline medium. Therefore, it has potential application in electrode materials of fuel cells field. Such as, Justin et al. researched that Pt-Nb2O5/C had good electrocatalytic activity toward methanol oxidation in acid medium [5]. In addition, the low cost nonprecious metal catalysts exhibit attractive activity in fuel cells? electrode. For example, Jiang et al. reported that Fe/Fe3C nanoparticles had high activity toward oxygen reduction reaction [6]. Therefore, in here, we synthesized Nb2O5-Fe3C@NCNTs composites and studied their electrocatalytic activity toward the methanol and ethanol oxidation. 2. Experiments and Results The mixture of ferric chloride (FeCl3) and melamine was calcination under 800 ? for 2 h, then was rinsed several times with hydrochloric acid and water. The Fe3C@NCNTs particles were obtained after drying 12 h at 60 °C. Niobium oxalate and as-prepared Fe3C@NCNTs were dispersed in ethanol to form a uniform suspension. The suspension was hydrothemral for 12 h at 180 °C. Then, the mixture was cooled and centrifuged to obtain the black sediment. The black sediment was rinsed several times with doubly-distilled water and ethanol. This sediment obtained was dried under 60 °C for 12 h, then was calcined for 3 h at 700 °C. Last, the Nb2O5-Fe3C@NCNTs composite was obtained. The physical and chemical properties of samples were performed using XRD, SEM, TEM and XPS techniques. The XRD results indicated that pure Fe3C@NCNTs was successfully synthesized, and belonged to the unit of JCPDS 03-065-2413. From SEM images, we can be seen that the podiform Fe3C@NCNTs obtained with big specific surface area. The XPS performances implied that the valence state of iron element was main Fe2+ and Fe3+ forms on Fe3C@NCNTs and Nb2O5-Fe3C@NCNTs samples. The electrocatalytic activity of the Nb2O5-Fe3C@NCNTs composites was carried out by cyclic voltammetry (CV) in 0.5 M KOH aqueous containing 1 M methanol and ethanol, respectively. The CV results indicated that the Nb2O5-Fe3C@NCNTs composites modified Pt electrode had excellent electrocatalytic activity toward the oxidation of methanol and ethanol in alkaline medium. The enhanced electrocatalytic activity is due to the synergistic reaction between Nb2O5 and Fe3C@NCNTs and the big specific surface area. 3. Conclusions The Nb2O5-Fe3C@NCNTs composites with big specific surface area were successfully synthesized. The Nb2O5-Fe3C@NCNTs modified Pt electrode had excellent electrocatalytic activity toward the methanol and ethanol oxidation in alkaline medium. The synergistic reaction between Nb2O5 and Fe3C@NCNTs had an enhanced toward the electro-oxidation of methanol and ethanol. Acknowledgements The work is financially supported by the National Natural Science Foundation of China (21666024), the Natural Science Foundation of Inner Mongolia (2016MS0204) and Talent Development Foundation of Inner Mongolia. References? [1] Tan J.L., Jesus A.M.D., Chua S.L., Sanetuntikul J., Shanmugam S., Tobgol B.J.V., Kim H., Appl. Catal. A: General 2017, 531, 29-35. [2] Jiang Z., Zhang Q., Liang Z.X., Chen J.G., Appl. Catal. B: Environmental 2018, 234, 329-336. [3] Zhou Y., Y.F. Gao, Liu Y.C., Liu J.R., J. Power Sources 2010, 195, 1605-1609. [4] Rajesh D., Neel P.I., Pandurangan A., Mahendiran C., Applied Surface Science 2018, 442, 787-796. [5] Justin P., Charan P.H.K., Rao R.G., Appl. Cata. B: Environmental 2010, 100, 510-515. [6] Jiang W.-J., Gu L., Li L., Zhang Y., Zhang X., Zhang L.-J., Wang J.-Q., Hu J.-SW., Wei Z.-D., Wan L-J., J. Am. Chem. Soc. 2016, 138, 3570-3578.

Resume : Supercapacitors have attracted significant attention for energy storage due to their outstanding merits, including high power density, long cycle lifetime, and high reliability. Currently, cathode materials are being extensively studied; this has led to the development of high-performance cathodes for aqueous supercapacitors, and some of them have even achieved their theoretical capacitance. Energy density of asymmetric supercapacitors (ASCs) is greatly limited by the electrochemical performance, especially low specific capacitance and poor cycling stability, of anode materials. To achieve high performance ASCs, herein, we designed and synthesized a new anode material of Fe3+ modified V2O5@ graphene Quantum Dots (m-V2O5@GDQs). When applied as an electrode material for supercapacitors, hierarchical m-V2O5@GDQs hybrid shows an ultrahigh specifc capacitance (760 F g-1 at a current density of 2 A g-1) with exceptional rate capability, and admirable cycling performance (87 % capacitance retention after 10 000 cycles). Furthermore, a solid-state asymmetric supercapacitor device assembled with N-C@MnO2 as a cathode and m-V2O5@GDQs as an anode exhibits a high energy density of 99.2 W h kg-1 at 320 W kg-1 power density without compromising long cycle life (ca. 81 % retention after 10000 cycles). The highly efficient energy storage performance of this new class of heterostructures synthesized with earth-abundant materials enables commercial applications.

Resume : Two-dimensional (2D) materials, such as graphene, MXenes, transition metal oxides/hydroxides, have been extensively investigated recently as active materials in energy storage. Assembly of 2D nanosheets into a three-dimensional (3D) macroscopic architecture is important for many practical applications. Here, we demonstrate a universal gelation method of reduced graphene oxide and MXenes into 3D structured hydrogel. With the controllable drying processes, freeze-drying and capillary drying, reduced graphene oxide/MXenes (rGO/MX) hydrogels may transform into different monoliths in loosely organized aerogel and dense solid, respectively. The resulted 3D rGO/MX macroassembly in foam form exhibits a high adsorption performance to remove various classes of organic liquids and heavy metal ions and the one in dense form displays a high Young's modulus and hardness, demonstrating their potential applications in environmental remedy, mechanics and energy storage fields. For energy storage application, the self-restacking of rGO and MXenes nanosheets is effectively prevented, leading to a considerably accelerated diffusion of electrolyte ions. The fabrication of rGO/MX hydrogel was demonstrated for as a 3D ultrafast supercapacitor. The rGO/MX displays a high gravimetric capacity of 510 F/g at a current density of 0.5 A/g in H2SO4 electrolyte, an impressive rate capability with 56% capacitance retention at 100 A/g and long cycle life. Besides, we show the high efficacy of the 3D macroscopic scaffolds rGO/MX as cathode hosts for Li-S batteries. And the S@rGO/MX composites exhibit stable long-term cycling performance because of the rGO/MX composite enabling smooth trapping?diffusion?conversion of polysulfides. Capacity retention of 82% is achieved over 500 cycles at a 2C current rate. References 1. Li, H.; Tao, Y.; Zheng, X.; Luo, J.; Yang, Q. -H. et al, Energy Environ. Sci. 9, 3135 (2016) 2. Lukatskaya, M.; Kota, S.; Lin, Z.; Simon, P. et al, Nature Energy 6, 1 (2017) 3. Zhou, T.; Lv, W.; Li, J.; Zhou, G.; Yang, Q. -H. et al, Energy Environ. Sci. 10,1694 (2017)

Resume : Ni-particles in the range of 50nm to 2?m were electrodeposited on polished Born-Doped Diamond. The interspace between particles was controlled with the help of Anodic Aluminum Oxide Template. The influence of Ni-nanoparticles on the diffusion regime has been studied.

Resume : Carbon materials are ubiquitous in electrodes for lithium/sodium-ion batteries, acting as active material, functional additive, or both. Here we report on our work involving spray-drying for the preparation of composite powders of carbon with another inorganic material. Spray-drying [1] is a versatile technique which can handle both solutions and suspensions and offers good reproducibility and easy scaling-up of production. Here we report results on silicon/carbon [2] and (fluoro)phosphate/carbon [3-5] composites prepared by addition of a solid carbon source (such as carbon nanotubes) in the liquid feedstock and/or by addition of soluble precursors whose in situ formation of carbon is achieved by a heat treatment in inert atmosphere. This work relies on the characterization of the spray-dried precursors, heat-treated powders and electrode materials through compositional, structural, microstructural and electrochemical techniques. [1] Vertruyen et al., Materials 11 (2018) 1076; [2] Eshraghi et al., in preparation; [3] Brisbois et al., Sol. Energ. Mat. Sol. C. 148 (2016) 67; [4] Eshraghi et al., Electrochim. Acta 228 (2017) 319; [5] Mahmoud et al., J. Solid State Electrochem. 22 (2018) 103

Resume : Lithium metal is generally recognized as one of the most promising rechargeable battery anode for its high highest theoretical specific capacity and lowest reduction potential. However, the harmful formation of Li dendrite on lithium metal hinders its further application. Hence, we propose a graphene oxide (GO) modified Cu foil as the dendrite-free current collector for lithium metal battery. Due to the redox reaction between the immersing Cu foil and the GO solution, the GO film is directly grown and self-assembles on the Cu foil. Benefiting from the synergistic effect of enhanced lithiophilicity, coverage of the active nucleation sites on the Cu foil and regulation of metal Li deposition, the GO modified Cu current collector based anode exhibits improving cycle stability and high Columbic efficiency. As a result, facilely fabricated the GO modified Cu foil can be a potential candidate for the stable current collector of lithium metal battery.

Resume : Carbon structures, with 1D, 2D and/ or 3D morphologies carry with them the intrinsic advantages of availability, low carbon-footprint, economics and disposal-management. Therefore, they continue to be an integral and critical component of all economically viable energy storage systems. Carbon structures have also been found to facilitate transport of ions like Li+, Na+, etc. It is being envisaged that synergistic combination of Na-ion based cathode and carbon-based anode can make next generation Na-ion supecapacitors useful for large scale integration. In this work, it will shown that, combining the strategy of using high perfoeming hollow nanostructures of Na-based electrode material with carbon nanostructures, can lead to significant enhancedment in the electrochemical performance. The electrochemical values returned by hollow structures of NaFePO4 are more than 70% higher than those delivered by conventional solid, porous or other hieararchical nanostructures. In the full device configuration, NaFePO4 is combined with various synthesized carbon nanostructures ranging from quantum dots, microshperes, etc. These combinations have their advantages and disadvantages. But, one result is common ? ?the performance of Na-ion based supercapacitors become comparable to Li-ion or many other expensive metal oxides based supercapacitors?. For use in applications such as hybrid vehicles, temperature stability of the storage device is absolutely essential. Temperature dependent results of the fabricated device prove that NaFePO4 can be easily used upto 70oC, with practically no loss in the observed Columbic efficieny.

Resume : PEC oxidation technique is a promising advanced oxidation process for treating the low-centration pollutants in the waters. The external anode bias was used to guide photo-generated electrons (e-) moving to cathode through external electric circuit to inhibit the rapid recombination of e- and h+, so that an improved oxidation efficiency can be achieved. However, the addition of external anode bias will raise the total energy consumption in the PEC process, and the oxidation pathway of the contaminates together with the generation and conversion of reactive oxygen species may be affected. In this work, TiO2 nanotube arrays (TiO2 NTs) was fabricated. Atrazine (ATR) was selected as the target pollutant, which was a kind of pesticide and EEDs. Anode bias adjusted PEC oxidation of ATR on TiO2 NTs surface were investigated in detail. The results found that enhanced PEC oxidation of ATR could be achieved compared with PC oxidation. However, the removal efficiency was not increased linearly with the bias potential. The mechanism investigation revealed that in the PEC process, the external anodic bias can achieve rapid separation of e- and h+. With the bias increasing, although the apparent rate constant of ·OH generation was almost constant, but the ability of h+ directly oxidizing ATR was improved effectively. Besides the e- remained on the TiO2 NTs surface can also react with dissolved oxygen to form ·O2-, which can lead to the fast and enhanced oxidation ability towards ATR. This process was highly influenced by the pH value of the solution. This work was supported by the National Natural Science Foundation P.R. China (Project No. 21677110 and 21537003), and the Fundamental Research Funds for the Central Universities (22120180118).

Resume : To fabricate high-performance supercapacitors with both high power and energy densities, three-dimensional 3C-SiC/graphene hybrid nanolaminate films grown via a microwave plasma-assisted chemical vapor deposition technique have been employed as the capacitor electrodes. Such films consist of three-dimensional alternating structures of vertically aligned 3C-SiC and graphene layers, leading to high surface areas and excellent conductivity. Their uses of electrical double layer capacitors (EDLCs) and pseudocapacitors (PCs) in both aqueous and organic solutions revealed that the capacitance for an EDLC in aqueous solutions is up to 549.9 µF cm-2, more than 100 times higher than that of an epitaxial 3C-SiC film. In organic solution, it is 297.3 µF cm-2. The pseudocapacitance in redox-active species (0.05 Fe(CN)63-/4-) contained aqueous solutions is as high as 62.2 mF cm-2. The capacitance remains 98% of initial value after 2500 charging/discharging cycles, indicating excellent cyclic stability. In redox-active species (0.01 M ferrocene) contained organic solutions, it is 16.6 mF cm-2. Energy and power densities of a PC in aqueous solution are 11.6 W h kg-1 and 5.1 kW kg-1, respectively. The comparison of these values with those for individual SiC and graphene capacitor electrodes confirms that vertically aligned 3C-SiC/graphene hybrid nanolaminate films are thus promising electrode materials for energy storage applications.

Resume : 3,3'-([2,2'-bipyridine]-5,5'-diylbis(methylene))bis(1-(4-(methoxycarbonyl)benzyl)-1H-imidazol-3-ium) hexafluorophosphate [BDBMBIm(PF6)2] ionic liquid was used as functional monomer to coordinate with Zinc ions to synthesize metal-organic frameworks (Zn-MOFs) under a one-step solvothermal method. Ammonium molybdate and thiourea were introduced into the pores of the as-prepared Zn-MOFs under vacuum. After being filtered, Zn-MOFs were transferred to a ceramic vessel. Then, the mixture was heated to 220 oC in a tube furnace under the protection of nitrogen. Kept reacting for 3 h, the product was annealed at 700 oC for 3 h to produce carbon@MoS2/ZnS nanocomposite. Carbon@MoS2/ZnS nanocomposite was thoroughly characterized by FTIR, TEM, SEM, XPS and nitrogen-adsorption. Carbon@MoS2/ZnS nanocomposites were modified onto a glassy carbon electrode surface to construct a photosensitive platform for immobilizing antibody protein to fabricate a photoelectrochemical immunosensor for tumor biomarkers. The results indicate carbon@MoS2/ZnS nanocomposites shows excellent photoelectric conversion efficiency. The photoelectrochemical immunosensor also possess good sensitivity, selectivity, and stability towards the target tumor marker.

Resume : A series of reduced graphene oxides (rGO) integrated with Bi-rich Bi4O5Br2 were prepared via a facile one-pot solvothermal method. The as-prepared rGO/Bi4O5Br2 nanocomposites were fully characterized with Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and high resolution transmission microscope (HR-TEM). The results confirm the successful integration of Bi4O5Br2 on rGO nanosheets surface. As a photocatalyst for the degradation of tetracycline hydrochloride (TC) and ciprofloxacin (CIP), the rGO/Bi4O5Br2 nanocomposites demonstrate more efficient than the pure Bi4O5Br2 under the simulated solar irradiation. When rGO was controlled at 1 wt%, the produced rGO/Bi4O5Br2 nanocomposites can exhibit the best activity. It can eliminate 97% of TC and 98% of CIP within 60 min. The improved photocatalytic performance can be attributed to the enhanced light absorption and the rapid photo-carrier separation after the loading of reduced graphene oxides. Based on the data obtained from electron spin technique (ESR), XPS and diffuse reflectance spectrum (DRS), the mechanism for the photocatalytic process has been illustrated. This study offers an efficient photocatalyst for the photodegradation of antibiotics with high performances under solar light.

Resume : Thermal management has become a critical issue to enhance reliability and performance in many research areas including aerospace, electronic devices, and military applications. However, conventional nanocomposites incorporated with highly thermally conductive nanofillers can hardly achieve a desired value, due to the existence of large interfacial thermal resistance (ITR) which constitutes a primary bottleneck. Herein, we report on a bioinspired interfacial engineering strategy to construct a multi-dimensional filler structure composed of 2D GNPs, 0D AgNPs and bioinspired interfacial PDA layer, namely pGNPs@Ag. The experimental results revealed that a high-efficiency thermal conductivity enhancement was achieved by this strategy, due to that the bridging connections of decorated AgNPs could facilitate the heat transfer across the interfaces. By theoretical simulation and calculation, we also quantitatively demonstrated a decrease of ITR by pGNPs@Ag, leading to a contribution to improve the k of composites. This approach for constructing multi-dimensional thermally conductive fillers potentially provides a creative opportunity for design and fabrication of high thermally conductive composites in the near future.

Resume : Facile and low-cost synthesis routes of highly efficient electrode materials for applications in electrochemical energy storage devices are imperative. In this work we constructed nickel-copper alloy nanoparticles through decomposition of metal-organic frameworks (MOFs) at an elevated temperature under nitrogen atmosphere. Our method includes NiCu bimetallic nanoparticles embedded carbon matrix rejected from 1,3,5-tricarboxylic acid as an organic molecule. Owing to higher porosity and a greater specific surface area, NiCu@C shows high capacitance and longer life in a supercapacitor. Such materials provide binary active sites and an ability to mass transfer rapidly. Consequently, we suppose that this work would provide an insights and designed into low cost synthesis method of 3D structured MOFs for electrochemical energy storage electrode materials.

Resume : In the past decades, electrochemiluminescence (ECL) which emits light by electrochemistry have attracted more and more attention in analytical chemistry due to its high sensitivity and good controllability. In the past years, our research group have focused study on the ECL behaviors and reaction mechanisms of carbon nanomaterials including carbon quantum dots (CQDs), graphene quantum dots (GQDs), carbon nanotubes (CNTs). We found that these carbon nanomaterials exhibited good ECL properties in aqueous solutions. It was revealed that the ECL activities of carbon nanomaterials were highly dependent on the surface states of carbon nanomaterials. The further applications of the ECL carbon nanomaterials in analytical chemistry have been explored, and sensitive, green, low-cost sensing methods based on carbon nanomaterials have been established.

Resume : It is of fundamental and practical significance to translate the novel physical and chemical properties of individual graphene nanosheets into the macroscale by the assembly of graphene building blocks into macroscopic architectures with control over the porous structure and functionalities. 3D graphene aerogels have some interesting properties such as high specific surface area, open porous network for ion transport, flexibility, tough mechanical strength and conductive framework which lend them high potential for wide application fields such as supercapacitors, oil-water separations, sorbents, chemical reactor platforms and solar cells [1]. One way to prepare 3D aerogels is starting from GO dispersions and its gelation under hydrothermal conditions [2]. Upon hydrothermal treatment, the functional groups of GO nanosheets are removed by reduction resulting in a decrease of hydrophilicity and loss of surface charges, which leads to the crosslinking of RGO nanosheets and ultimate phase separation. Herein, we have varied the hydrothermal synthesis conditions (pH, time, and freezing method) to achieve a control over the orientation and size of the pores in graphene aerogels. Moreover, the pH of the initial solution has a profound impact on the reduction degree and morphology of the individual graphene nanoplatelets. As a proof of concept, the materials have been tested as hydrophobic absorbents of organic compound, as supercapacitors and as support for nanodiamonds metal-free catalyst for selective propane dehydrogenation [3]. As supercapacitors, the time of hydrothermal treatment was the critical parameter to attain optimum specific capacitance. References [1] Chabot, V.; Higgins, D.; Yu, A.; Xiao, X.; Chen, Z.; Zhang, J., Ener. Environ. Sci., 7 (2014) 1564. [2] E. Garcia-Bordeje, S. Victor-Roman, O. Sanahuja-Parejo, A.M. Benito, W.K. Maser, Nanoscale, 10 (2018) 3526-3539. [3] Roldan, L.; Benito, A. ; Garcia-Bordeje, E., J. Mater. Chem. A, 3 (2015) 24379 Aknowlegement The financial support from Spanish Ministry MINECO and the European Regional Development Fund (project ENE2016-79282-C5-1-R) and Government of Aragon (Consolidated Group DGA-T66).

Resume : Although some progress has been made in flexible supercapacitors (SCs), their high energy density, mechanical robustness, and device-level editability and programmability are still highly desirable for the development of advanced portable and miniaturized electronics, especially considering the fact that these flexible devices are likely to experience some mechanical impact and potential damage. Herein, we demonstrate the fabrication of hybrid electrodes containing self-assembled 2D metal?organic framework (MOF)/reduced graphene oxide (rGO) papers, which not only efficiently alleviate the selfrestacking of rGO and the MOF but also maintain high electrical conductivity (0.32 U cm), excellent flexibility and mechanical properties with a Young's modulus of 34.4 GPa and a tensile strength of 89.9 MPa. In addition, a one-for-two strategy is introduced to construct two types of porous electrodes for flexible asymmetric SCs via a one MOF-derived synthesis route with simply changing metal ion precursors. As a consequence, the flexible asymmetric SCs possess a high volumetric energy density of 1.87 mW h cm
3 and an outstanding volumetric power density of 250 mW cm
3. More importantly, the all-solid-state asymmetric SCs exhibit high editability and bending-tolerance properties and perform very well under various severe service conditions, such as being seriously cut, bent, and heavily loaded. Particularly, the operations of micro-SCs with artistically designed patterns are demonstrated. Being high-strength, easily programmable and connectable in series and in parallel, the editable supercapacitor is promising for developing stylish energy storage devices to power various portable, miniaturized, and wearable devices

Resume : Developing highly efficient bifunctional electrocatalyst for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is of great importance in fuel cells and metal-air batteries. Among all candidates, non-precious transition metal composite materials with appropriate components and nanostructures might be promising for ORR and OER. Herein, we synthesized a composite containing CoMn alloy coated with N-doped carbon and MnO by a facile strategy of annealing Prussian blue analogues (PBA). The derived heterogeneous composite Mn2Co3-900 includes the merits of CoMn alloy, N-doped carbon and MnO, showing a low onset potential of 0.91 V, positive half-wave potential of 0.76 V and large limiting current density of 5.8 mA cm-2 among controlled samples. We proposed the enhanced ORR activity attributed to the optimal surface electronic configuration of alloy beneficial to dissociate intermediates and heterojunctions favoring charging transfer from alloy and oxide. In addition, this catalyst also shows promising activity for OER with onset potential of 1.53 V and low potential of 1.65 V at 10 mA cm-2. This work therefore highlights the importance to construct alloy and oxide composite catalysts for superior electrocatalytic reaction.

Resume : BiOI-Bi@carbon composite was prepared via a one-step solvothermal method and employed as visible light-activated material to construct a novel cathodic photoelectrochemical (PEC) aptasensor for highly sensitive and selective detection of chloramphenicol (CAP). The composite displayed a 3D flower-like hierarchical microstructure and exhibited an enhanced cathodic photocurrent as compared with pure BiOI, owing to the surface plasmon resonance (SPR) effect of Bi and high conductivity of carbon. When CAP-binding aptamer was immobilized as recognition element on BiOI-Bi@carbon modified electrode, a cathodic ?signal-on?? PEC aptasensor for detection of CAP was obtained. Some influencing factors such as coating amount of BiOI-Bi@carbon suspension, applied bias potential, and aptamer concentration were studied and optimized. Under the optimum conditions, the fabricated PEC sensing platform showed a linear response to CAP in the concentration range from 2 to 250 nM, with a detection limit (3S/N) of 0.79 n?. The proposed sensor was successfully applied to the determination of CAP in pharmaceutical tablet, eye drop and lake water.

Resume : A novel photoelectrochemical (PEC) aptasensor of PCB72 based on CdS-rGO-g-C3N4 composite was designed, which exhibited enhanced PEC intensity compared with pure CdS and g-C3N4. In this work, H2O2 was exploited as an efficient and non-poisonous electronic donor for capturing photogenerated holes, simultaneously, PCB72-binding aptamer was employed as a recognition element. The doping of g-C3N4 in CdS promoted its visible light absorption range and facilitated the charge transfer rate as well as hindered the h+/e- recombination. Moreover, the combination of rGO further promoted the electron carrier separation and transfer process due to its excellent electron collection and shuttling characteristic. Thus, the CdS-rGO-g-C3N4 heterostructure was successfully served as a matrix for the PEC detection of PCB72 at 0 V (vs. SCE). Under optimal conditions, the PEC aptasensor could offer a 8sensitive and specific detection limit (3 S/N) of PCB72 down to 1.0 ng/mL, as well as acceptable reproducibility, selectivity and storage stability, which provided a feasible solution for detection of PCB72.

Resume : The catalytic activity of metal nanocatalysts generally decreases due to the agglomeration of unstable nanocatalysts during the catalytic reaction. Therefore, the well-arranged incorporation of catalytically-active metal nanoparticles within porous materials is very important to preserve their original activity by preventing the agglomeration of unstable nanocatalysts. Herein, we present a convenient method for the well-arranged incorporation of bimetallic PdCo nanocatalysts within unique hollow and porous carbon material or metal-organic framework (MOF) support. Several chemical conversions occur simultaneously during one-step low temperature pyrolysis of polystyrene@ZIF-67/Pd2 core-shell microspheres [where ZIF (zeolitic imidazolate framework) is a subclass of MOF]: the polystyrene core within a core-shell microsphere is removed, and so resulting in a hollow support; the ZIF-67 shell acts as a well-defined porous support and also as a appropriate Co2 supplier for the formation of metal nanocatalysts; and Pd2 and Co2 are reduced to form catalytically-active bimetallic PdCo nanoparticles. The resulting composites show a superior catalytic activity owing to the unique hollow and porous features of support and the well-arranged incorporation of highly-active bimetallic PdCo nanoparticles within a unique hollow and porous support.

Resume : Metal-organic frameworks (MOFs) have received great attention due to their attractive structural features and useful applications. In particular, the structural features of MOFs are vital in defining their properties and applications. Indeed, well-developed porosity and high surface area of MOFs are the most essential structural features, and many practical applications of MOFs originate from these structural features. On the other hand, several convenient methods for the generation of the customized metal oxide or carbon materials have been developed by using MOF materials. Particularly, a pyrolysis of MOFs under an inert atmosphere produces useful carbon materials. Herein, we present the construction of core?shell type hybrid MOFs through the growth of MOF on the surface of MOF template, and the production of porous carbon materials with well-defined composition and so property through the simple pyrolysis of core-shell type hybrid MOF.

Resume : Nanopores with functional elements (FE) have shown promise for rapid DNA sequencing, sensitive single-molecule sensing and specific ion gating1, 2. Ionic current measurement is currently a benchmark but focused solely on the contribution from nanopores inner wall FE (NIWFE)3; the attributes of FE at nanopores outer surface (NOSFE) is nearly ignored yet remains exclusive. Here, we show that the role of NOSFE and NIWFE for ion gating can be distinguished by incorporating electrolytic current and ionic current signals through formation of exquisite DNA architectures acting as both molecular switch and ion gate, which behave continuously tunable and reversible ion gating ability. We find that NOSFE itself exhibits negligible ion gating behavior, but it can produce synchronously enhanced effect when alliance with NIWFE. Moreover, the high-efficiency gating systems display more noticeable synchronous effect than the low-efficiency ones. We also reveal that the probe amount of NOSFE and NIWFE is almost equally distributed in our biomimetic nanopores, which is potentially a premise for the synchronously enhanced ion gating phenomena. The uncovered ion gating function of NOSFE might be extended to nanopore-based DNA sequencing and single-molecule sensing.

Resume : Photovoltammetric behaviors of different electrochemical systems on CdS-graphene photoanode and BiOI-graphene photocathode were studied. Firstly, a photoelectroactive film composed of CdS quantum dots and graphene sheets (GS) was coated on F-doped SnO2 (FTO) conducting glass for studying the electrochemical response of p-phenylenediamine (PPD) under photoirradiation. The result indicated that the cyclic voltammogram of PPD on CdS-GS hybrid film became sigmoidal in shape after exposed under visible light, due to the photoelectrocatalytic reaction. The influences of scan rate and pH on the photovoltammetric behavior of PPD on CdS-GS film revealed that although the controlled step for electrochemical process was not changed under photoirradiation, more electrons than protons might participate the photoelectrocatalytic process. Furthermore, the photoelectroactive CdS-GS hybrid film was explored for PPD determination based on the photocurrent response of film toward PPD. Secondly, photovoltammetric behaviors of irreversible, quasi-reversible and reversible electrochemical systems represented by 2,4-dichlorophenol (DCP), hydroquinone (HQ) and K3[Fe(CN)6], respectively, were investigated on a CdS-graphene hybrid film electrode. The cyclic voltammetric (CV) curves of HQ and K3[Fe(CN)6] showing a pair of redox peaks became sigmoidal in shape under visible light irradiation. In contrast, the CV curve shape of DCP showing an oxidation peak was not changed under photoirradiation, although the oxidation peak current was enhanced by the photoelectrocatalysis. Thus, the reversibility-dependent photovoltammetric behaviors were observed. Furthermore, it was demonstrated that the photovoltammetric curve shapes were not changed by pH and intensity of light source, but were tunable with scan rate and concentration of reactants depending on the reversibility of the electrochemical reactions. Thirdly, a visible light-activated photocathode fabricated with p-type semiconductor bismuth oxyiodide (BiOI) and graphene (G) was employed to investigate the photovoltammetric behavior of chloramphenicol (CAP). The result indicated that the voltammetric reduction peak of CAP increased to a limiting current platform under photoirradiation, owing to photoelectrocatalytic reduction of CAP on the BiOI-G photocathode. As a result, the cathodic photovoltammogram became sigmoidal in shape. Based on such a BiOI-G electrode, a cathodic photovoltammetric sensor for CAP was proposed.

Resume : We produced electronic textiles (e-textiles) with graphene oxide (GO) and silk-based materials such as electrospun silk fibroin (SF) obtained from Bombyx mori (B. mori) silkworm, spider web, and commercial silk fabric. Since the SF is comprised of amino acids (alanine, glycine, and serine) having amine (-NH) and hydroxide (-OH), SF can be coated with GO through hydrogen bonding between the functional groups of GO and SF without any materials. The silk-based materials were immersed into GO solution via simple dipping and drying method. Thermal reduction can be also applied to fabrication process due to the fact that the silk based-materials are known as the pyroproteins, which are stable at high temperature. The electrical conductivity of e-textile showed 11.63 S/cm, which was maintained even in severe conditions. E-textiles need to have high heat durability for various applications. We also report silk-based e-textiles fabricated by simple pyrolysis with axial stretching that demonstrate high electrical conductivity and thermal durability. The electrical conductivity of the proposed e-textiles was on the order of 103 S/cm. Furthermore, we prepared e-textiles with various electronic properties such as superconductivity and piezoelectricity using sputtering and evaporation. We introduced a simple method for fabricating silk-based e-textiles with various electronic properties, which are compatible with the current textile industry.

Resume : To build high-energy density asymmetric supercapacitors, anode materials with large specific capacitance are highly required. In this work, the holey reduced graphene oxide (hrGO) prepared by a catalytic etching method was utilized as both anode and cathode to construct an asymmetric supercapacitor where two different electrolyte solutionswere applied. Regarding the cathode,The hrGOelectrode exhibits an ideal electrical-double layer capacity behavior with high specific capacitance up to 22.84 mF/cm2 at a scan rate 100 mV/s in 1 M Na2SO4with a potential range of ?1 and 0 V (vs. SCE).Regarding the anode, the hrGOelectrodeshows a pseudocapacitance of 22.72mF/cm2 at a scan rate of 100mV/sin 1 M Na2SO4 + 20 mM [Fe(CN)6]3-/4-within the potential range of -0.2 V ~ 0.8 V.Both the rGOanode and cathode only attain 70% specific capacitance value compared with hrGO, due to its unique porous structure. The optimized asymmetric supercapacitor cycled reversibly in thevoltage region of 0 - 2 V displays intriguing performance with a maximum specific capacitance of 101.25F g?1 at a charge/discharge current density of 5 A g-1. Furthermore, the supercapacitor device shows a high energy density of 56.25Wh kg?1 at a power density of 35.83kW kg?1 as well as an excellent long cycle life along with 85% specific capacitance retained after 2000 cycles. Therefore, this strategy is possibly utilizedin high energy density storage systems.

Resume : The development of sensitive and simple analytical method, especially the synthesis of sensing materials or systems, for detecting organic pollutants is very important because of their high biological toxicity to public health and environments. In this presentation, we will show the application of the composite of Fe2O3 with different morphologies (as sensing materials) with expanded graphite (EG) as the supporter of this sensing material. Three kinds of Fe2O3 materials with the morphologies of nanoplate (p-Fe2O3), nanorod (r-Fe2O3), and three-dimensional flower-like (f-Fe2O3) structure have been synthesized using solvothermal processes. Their composited with EG formed by means of ultrasonication have been further characterized using TEM, SEM, Raman, XRD, and electrochemical techniques. Their electroanalytic applications toward a series of organic pollutants like tetrabromobisphenol A (TBBPA), sunset yellow (SY), and tartrazine (Ta) have been systematically studied. Compared with p-Fe2O3, r-Fe2O3, the higher redox activity was achieved on the f-Fe2O3, leading to the best sensing performance towards TBBPA, SY, and Ta. Based on this, a novel sensing system with high sensitivity has been developed for TBBPA, SY and Ta, and the limit of detection was as low as 1.5 nM, 2.0 nM and 2.3 nM, respectively. This new sensing system has been successfully used in real samples, which shows a great potential for practical applications.

Resume : A novel electrochemical sensor for the phenol detection was fabricated using carbon-coated palladium oxide nanoparticles (PdO@C NPs) as sensing material and expanded graphite (EG) as the supporter of sensing material. Transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), and energy-dispersive X-ray spectroscopy (EDX) have been used for the characterization of structure,morphology, and composition of the nanocomposite. Highly dispersed PdO@C NPs with the size of about 11 nm have been uniformly attached on EG surface by ultra-sonication.Their electrocatalytic properties were investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Theywere further used for sensitive determination of a series of phenols including tetrabromobisphenol A (TBBPA), hydroquinone (HQ), and catechol (CC). The sensing signalsare significantly improved by the integration of PdO@C NPs onto EG nanosheets, leading tothe detection limits of as low as 1.3, 26 and 17 nM for TBBPA, HQ, and CC, respectively. Such a sensing system thus owns great application prospects in constructing a universal, highly sensitive, and selective electrochemical sensing platform for phenols.

Resume : Graphene, a flat monolayer of sp2-hybridized carbon atoms tightly packed into a 2D honeycomb lattice, is considered a promising candidate for applications in electronics, sensors, biomedical and energy storage devices, as well as several other cutting-edge technological fields. A successful implementation of graphene-based devices invariably requires precise patterning of the graphene sheets at the micrometer scale. Finding an ideal technique to achieve the desired graphene pattern with a high spatial resolution remains a major challenge. A variety of chemical and physical techniques including photolithography, soft lithography, and chemical vapor deposition have been adopted for the patterning of graphene sheets [1,2]. However, most patterning techniques involve complicated multi-step procedures, resulting in high operating costs. Here, we describe a simple and effective strategy to fabricate few-micrometer-wide graphene patterns by meniscus-guided printing, using a highly concentrated graphene oxide (GO, 2 wt%) ink. Our approach exploits the rapid solidification of an ink meniscus formed by horizontal pulling of a micronozzle [3-6]. To achieve uniform printing with continuous flow of the highly concentrated GO ink through the nozzle, polyvinylpyrrolidone (PVP), which acts as a gelation inhibitor and rheology modifier, was added to the aqueous GO solution. GO reduction and PVP removal from the printed patterns was achieved simultaneously, by thermal treatment. Electrical conductivities and widths of the reduced GO (rGO) patterns could be easily modulated by adjusting the nozzle-pulling rate and changing the nozzle-opening size, respectively. Toward applications in electronics, successful fabrication of a field-effect transistor (FET) based on a printed rGO channel is also described. Also, the rGO-FET showed reproducible photosensing as a function of the illuminating laser power. This approach can be effective for high-resolution printing of graphene patterns for electronic applications.

Resume : High heat durability of the electronic textiles (e-textiles) is required for the various applications such as semiconducting and superconducting flexible textiles. However, the e-textiles are usually not adoptable in the process which needs high temperatures. We report the e-textiles fabricated by pyrolysis of stretched silk fibroins and commercially used silk textiles with the highly electrical conductivity, flexibility, and thermal durability. The electrical conductivity of pyroprotein-based e-textiles shows the order of 10^3 S/cm, which results from long range order of carbon structure. It was confirmed that its electrical characteristics were retained even after heating and bending. In addition, the high thermal stability of the e-textiles allowed us to produce the ZnO-coated e-textiles using high-temperature processes such as sputtering and evaporation. We demonstrate simple methods to synthesize the multifunctional e-textiles without destroying the present textile industry.

Resume : The decentralized H2O2 generation via 2e- ORR pathway is a promising mean for environmental restoration. The density functional theory investigated the synergic effect of C-N/C?COOH group resulted in a minimum ?O2/H2O2 of 0.16 V to drive H2O2 formation. We developed a copolymerization method to introduce N dopants to the backbone of phenolic polymer aerogel. Of note, such a moderate amount of nitrogen dopant on the surface of carbon aerogel helps to selectively stabilize and optimize the COOH groups formed during the Na2CO3-assisted carbonization process. The optimized nitrogen-doped carbon aerogel electrode activated at 850 oC (NCA-850) gave a surprisingly 100% selectivity to two-electron process, exceeding previously reported carbonaceous and noble metal catalysts. The NCA-850 plate as a work electrode gave an evolution rate of 60 mg L-1 g-1 h-1 for H2O2 with satisfied mechanical and electrochemical stability for practical applications.

Resume : Carbon nanodots (C-dots) have great potential in a wide range of applications, such as detection, bioimaging, light-emitting devices, theranostics, drug delivery, etc. It is in high demand on the development of high-performance C-dots with high quantum yields (QYs) and tunable emissions to meet application requirements. However, the ambiguous photoluminescence (PL) mechanism results in the difficulty in controlling QYs and emission wavelengths of C-dots. In the work, the structure of C-dots, from surface oxygen-containing functional groups to carbon skeleton, were carefully controlled to study the effect of functional groups and ?-electron system on PL properties of C-dots. The functional groups and ?-electron system of the carbon nanodots (C-dots) prepared by wet oxidation were carefully controlled by the reduction of carbonyl groups and the elimination of hydroxyl groups, without any changes of the size. The results of experiments and theoretical calculations reveal that (I) the photoluminescence (PL) of C-dots is related to the surface state, where the energy gap is determined by the coupling of the ?-electron system and the carbonyl group, and (II) the carbonyl group is the main factor giving rise to a large ratio of non-radiation to radiation decay, thus bringing low quantum yield (QY) of C-dots. This work provides a new insight into the deep understanding of the fluorescence mechanism of C-dots, and enables to purposely tune the PL emission wavelengths with a highly desired QY of C-dots.

Resume : Flow-electrode-based capacitive deionization (FCDI) has attracted much attention owing to its continuous and scalable desalination process without the need for a discharging step, which is required in conventional fixed-electrode capacitive deionization. However, flow electrode slurry is poorly conductive, which restricts desalination performance, but higher carbon mass loading in the slurry could improve salt removal capacity due to enhanced connectivity. However, increased viscosity restricts higher loading of active materials. Herein, we report a significant increase in salt removal performance by introducing functionalized carbon nanotubes (FCNTs) into activated carbon (AC)-based flow electrodes, which led to the generation of conducting bridges between AC particles. The salt removal rate in the presence of 0.25 wt% FCNT with 5 wt% AC improved four-fold from that obtained with only 5 wt% AC, which is the highest value reported in the literature so far (from 1.45 to 5.72 mmol/m2s, at a saline water concentration of 35.0 g/L and applied potential of 1.2 V). Further, FCNTs with a high aspect ratio (~50,000) can more effectively enhance salt removal than low-aspect ratio FCNTs (~1300). Electrochemical analysis further confirms that the addition of FCNTs can efficiently form a connecting percolation network, thus enhancing the conductivity of the flow electrode slurry for the practical application of highly efficient desalination systems.

Resume : Hydrogels are highly water-absorbent 3D network used in numerous fields such as biotechnology, food and pharmaceutical industry. However, the potential of these materials in the energy domain has not yet been fully investigated. To bring new insights and perspectives, we have developed a macroporous electrode made of a conductive composite hydrogel. It is composed of sodium alginate, a polyelectrolyte that can form a biocompatible hydrogel when mixed with water in presence of divalent cations. The addition of carbon nanotubes in the dispersion before gelation leads to the formation of an electronically conductive network. Working with a sol-gel process enables to encapsulate and trap other functional particles in the composite hydrogel. In this talk, I will first present the mechanical and conductivity properties as well as the stability of this new hydrogel in various aqueous. Then, two applications taking advantage of these properties will be discussed. A first one concerns the encapsulation of exoelectrogenic bacteria in such a material. Their metabolism, which requires redox reactions, allows to transfer electrons from the bacteria to the macroporous electrode that acts then as a half biofuel cell. Then, I will show that such electrodes can work as a battery when lithium intercalation particles are encapsulated.

Resume : The diamond material possesses very attractive properties, such as superior electronic properties, large electrochemical potential window, and a controllable surface termination. Boron-doped diamond surfaces, with attached Pt nanoparticles as the catalytic surface, are nowadays working as a new class of electrode materials. The boron-doped diamond electrode is a semiconducting material with very promising properties like i) a wider potential window in aqueous solution, ii) low background current, and iii) corrosion stability in aggressive environments. The phenomena of diamond surface termination have experimentally been observed to significantly influence the broad-band infrared reflectivity and conductivity. H- terminated diamond surfaces have been found to be hydrophobic, and to show unique p-type surface electronic conductivity. On the other hand, oxygen-terminated diamond surfaces generally show hydrophilic properties, but no electronic conductivity. The surface reactivity of diamond is expected to affect both chemical processes at the surface and properties related to the surface electronic structure. Examples of factors with the capability to influence the surface reactivity are i) type of plane, ii) surface termination, and iii) doping. Theoretical modeling based predominantly on Density Functional Theory (DFT) has during the last decade proven to become highly valuable in the explanation and prediction of experimental results. The simulation and theoretical analysis of especially surface reactivities has been shown to aid important information. At this presentation, the effect of surface plane, termination and doping (B, N, P, S) on diamond surface reactivity and properties, will be especially highlighted by showing a number of examples from the fields of a) diamond growth, b) electrochemistry on diamond-based electrodes, c) temperature induced diamond-to-graphene formation, and d) functionalization of diamond surfaces in the field of bioimplants (especially bone regeneration). All results are based on high-level calculations using DFT (QM), ab initio Force field (MM) calculations, and hybrid QM/MM methods.

Resume : Like bulk diamond, nanodiamonds behave a versatile surface chemistry, which strongly governs their surface electronic structure. Hydrogenated detonation nanodiamonds (H-DND) exhibit specific assets based on a negative electron affinity [1]. A radiosensitization behavior was reported in-vitro for H-DND using radioresistant human cancer cells under gamma irradiation [2]. One remaining challenge consists in a better understanding of the H-DND surface chemistry, especially to assess a quantification of the C-H bonds. It is also essential to identify physical and chemical mechanisms at the origin of this radiosensitization effect. This presentation will first focus on an isotopic labeling of DND using deuterium (2H) or tritium (3H). A robust and scalable method to control 2H and 3H incorporation in DND using a closed system using deuterium or tritium gases was optimized. The surface chemistry of 2H- and 3H-DND was investigated by 13C NMR, Raman and FTIR. The quantification of 3H led to determine the amount of C-H terminations and their nature. Colloidal properties of 2H-DND and 3H-DND suspended in water were characterized by DLS. Moreover, ND can act as an active nanoparticle under excitation. Indeed, the possibility to use hydrogenated diamond surface as a solid source for the production of solvated electrons usable for CO2 reduction was evidenced by the pioneer work of Hamers et al. [3]. The second part of the presentation will focus on the quantification of hydroxyl radicals and solvated electrons produced by aqueous suspensions of DND of different concentrations under irradiation either with X-rays (17.5 keV) or gamma rays (1.17 MeV) [4, 5]. The overproduction of hydroxyl radicals and solvated electrons will be discussed considering the possible role of the surface chemistry of DND, the diamond core and the water interface. References [1] J.C. Arnault, H. A. Girard, Current Opinion in Solid State & Materials Science, 2017, 21, 10. [2] R. Grall, H. A. Girard, L. Saad, T. Petit, C. Gesset, M. Combis-Schlumberger, V. Paget, J. Delic, J. C. Arnault, S. Chevillard, Biomaterials, 2015, 61, 290. [3] R. J. Hamers, J. A. Bandy, D. Zhu, L. Zhang, Faraday Discuss, 2014, 172, 397. [4] C. Sicard-Roselli, E. Brun, M. Gilles, G. Baldacchino, C. Kelsey, H. McQuaid, C. Polin, N. Wardlow, F. Currell, Small 2014, 10, 3338. [5] M. Kurzyp, H. A. Girard, Y. Cheref, E. Brun, C. Sicard-Roselli, S. Saada, J. C. Arnault, Chem. Commun., 2017,53, 1237.

Resume : Two kind of diamond-graphite nanohybrid (DGN) films with different microstructures were grown via microwave plasma enhanced chemical vapor deposition (MPCVD) technology, in which liquid diethylamine, containing carbon and nitrogen atoms, was used as a sole reactive source. At low temperature (730), planar ultrananocrystalline diamond (UNCD) film was obtained. Increasing the deposition temperature to 820, the morphology and microstructure of DGN films exhibited a huge change into a novel nanocrystalline diamond/vertical multilayer graphene (ND/MLG) film. Hydrogen evolution reaction (HER) performance of two DGN films were compared. The over-potential of the ND/MLG film was only 111 mV, and the Tafel slope was 49 mV•dec-1; whereas, these values of the UNCD film increased to about 214 mV and220 mV•dec-1, respectively. This obvious enhancement in HER performance could be attributed to a large number of edge planes in the vertical multilayer graphenes, which would provide electrochemically-active sites.

Resume : Upon contact with physiological medium, nanoparticles (NPs) will be covered by a protein corona layer. This protein corona alters not only the surface property of NPs, but also their interactions with biological system. Understanding the corona formation process is crucial for predicting the biological fate of NPs. It is reported that hydrophobic interactions and electrostatic attractions were the driving forces for protein attachment 1), but there is lack of stoichiometric description of these interactions. Here, we quantitatively evaluate NP hydrophilicity to protein affinity. Nanodiamond (ND) coated by polyethylene glycol (PEG) and polyglycerol (PG) in different density were used as hydrophilic platforms. Bovine serum albumin (BSA), gamma globulin (Ƴ-GLO), and fibrinogen (FIB) were selected as model proteins. Corona proteins were identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and quantified via bicinchoninic acid assay (BCA). The results indicated that BSA and Ƴ-GLO formed monolayers on the bare ND surface, while FIB formed multilayer corona. The number of protein molecules on a single ND decreased from 193 to 11 as PG density increased from 10 to 20 wt%. In particular, there was no protein on ND-PG surface when PG density reached 30 wt%. Taking advantage of the transparent background of PG, we further investigate the net charge effect; some of the hydroxy groups on PG were substituted by amino and carboxyl groups which gave plus and minus surface potentials, respectively 2). Their affinity toward various proteins with different isoelectric point will be quantified. References: 1) R. Haag et al., Angew. Chem. Int. Ed., 2014; 2) L. Zhao, N. Komatsu and et al., Adv. Funct. Mater., 2014

Resume : Cell is the fundamental unit of life, and fast and accurate acquirement of the biomolecule information at the single cell level is of great significance to better understand the life process. Electrochemical methods play important roles in real-time monitoring of cells, and a wide variety of carbon-based materials have been used for construction of high-performance electrochemical sensors. In this talk, I will introduce our recent work on the development of novel carbon-based sensors and exploring their applications in real time monitoring of cells. 1. We developed some multifunctional (e.g. highly sensitive, highly selective, reusable, and cell compatible) electrochemical sensors based on carbon nanotubes, graphene, and carbon composites, and monitored various kind of chemical messengers release from single cells in real time.[1-3] 2. We developed high-performance stretchable electrodes based on interlacing networks of gold nanotubes and Carbon nanotubes, which allows, for the first time, real-time electrochemical monitoring of mechanically sensitive cell and tissues.[4-7] 3. We fabricated carbon fiber nanoelectrode and developed nanoelectrode amperometric method for probing into single synapse; We also fabricated single SiC@C nanowire electrode for intracellular detection. This Opens a new window for nanometer-sized electrochemical sensors in explorations of physiological processes at the subcellular level.[8-10] Reference: 1. Y. L. Liu, et al. Chem. Sci. 2015, 6, 1853-1858. 2. J. Q. Xu, et al. Angew. Chem. Int. Ed. 2015, 54, 14402-14406. 3. X. B. Hu, et al. Anal. Chem. 2018, 90, 1136-1141. 4. Y. L. Liu, et al. Angew. Chem. Int. Edit. 2016, 55, 4537-4541. 5. Z. H Jin, et al. Anal. Chem. 2017, 89, 2032-2038. 6. Y. L. Liu, et al. Angew. Chem. Int. Edit. 2017, 56, 9454-9458. 7. Y. W. Wang, et al. Anal. Chem. 2018, 90, 5977-5981. 8. Y. T. Li, et al. Angew. Chem. Int. Ed. 2014, 53, 12456-12460. 9. Y. T. Li, et al. Angew. Chem. Int. Ed. 2015, 54, 9313-9318. 10. X. W. Zhang, et al. Angew. Chem. Int. Ed. 2017, 56, 12997-13000.

Resume : Graphene has been shown to be a promising barrier for thermal corrosion due to its low gas and liquid permeability; however, there have been contradictory reports in the literature regarding the mechanisms of oxidation of graphene-coated Cu. This work systematically investigates the effect of chemical vapor deposited graphene grain size, point defect density, and underlying Cu orientation on the thermal oxidation of the underlying Cu in air. For graphene with either small grain size (~0.04?0.4 micron^2) or large point defect density (~803 micron^-2), oxidizers have relatively unhindered access through these defects to corrode the underlying Cu, and the corrosion is relatively independent of Cu orientation. For graphene with low defect density, the rate of Cu oxidation is limited by the quality of the graphene grown on the specific Cu crystal orientation and the orientation with the weakest graphene-metal interaction. It is shown that the surface of graphene-coated Cu (110) is completely corroded up to at least the detection depth of Auger Electron Spectroscopy (AES) in just 2 min of thermal oxidation at 250 degrees C, while AES detects no Cu oxide at the surface for graphene-coated Cu (111). Graphene-coated Cu (100) performs in the intermediate with 56% Cu metal detected on the surface.

Resume : 3D printing, also known as additive manufacturing, provides a unique tool for prototyping structures towards electrochemical sensing and biosensing, due to its ability to produce highly versatile, tailored-shaped devices in a low-cost and fast way with minimized waste. Herein, we demonstrate the potential of 3D printing in electroanalytical applications, by manufacturing graphene-based electrodes with a Fused Deposition Modeling printer. The as-printed electrodes are electrochemically inactive and require pretreatment for activation, which arises from the high bulk content of the thermoplastic polymer concealing the electrodes after 3D printing, hindering the conductive and electroactive carbon-based part from exposition to the electrolyte. We have investigated different activation procedures, namely solvent-assisted and enzymatic digestion, in order to expose electroactive graphene sheets embedded within the 3D-printed structures to the solution and therefore to achieve tailorable electrode performance. The 3D-printed electrodes before and after activation were characterized in terms of morphological changes (by scanning electron microscopy and optical microscopy), surface chemistry (infrared spectroscopy), bulk analysis (water uptake, mass loss), and electrochemical response (cyclic voltammetry) towards different redox probes. The solvent-assisted activated electrodes were applied in the detection of picric and ascorbic acid, whereas the enzymatically-digested structures were used as biosensing proof-of-concept involving the immobilization of alkaline phosphatase and detection of 1-naphthol as catalytic product. Such customizable platforms represent promising alternatives to conventional electrodes for a wide range of electroanalytical applications.

Resume : The development of sustainable energy technologies such as fuel cells [1] is nowadays of outmost importance due to the increasing energy demand in our society; however, these technologies are limited by the several drawbacks of the state-of-the-art Pt/C catalysts used to enhance the cathode kinetics of the oxygen reduction reaction (ORR) [2]. In the last years, doped carbon nanomaterials have been proposed as efficient alternative to Pt-based catalysts due to large specific surface area, cost effectiveness and outstanding electrical and mechanical properties [3]. In particular, carbon nano-onions (CNOs) have recently shown promising ORR performance after mono-[4, 5] and dual-atom doping process [6]. Herein, we report the synthesis of boron/nitrogen-codoped carbon nano-onions (BN-CNOs) by a low cost thermal annealing process. The ORR activity have been investigated in alkaline media and our results showed remarkable catalytic performances via a four-electron pathway and higher long-term stability compared to the standard Pt/C catalysts [6]. Our findings confirm that CNO electrocatalysts are promising candidates to replace the expensive Pt catalysts in fuel cells. [1] B.C.H. Steele et al., Nature 414, 345 (2001). [2] D.J. Berger, Science 286 (5437), 49 (1999). [3] N. Daems et al., J. Mater. Chem. A 2, 4085 (2014). [4] E. Y. Choi et al., Sci. Rep. 7, 4178 (2017). [5] Y. Lin et al., J. Mater. Chem. A 3, 21805 (2015). [6] A. Camisasca et al., ACS Appl. Nano Mater., 1, 5763−5773 (2018).

Resume : Surface enhanced Raman scattering (SERS) probes based on charge transfer (CT) process with high stability and reproducibility is a powerful tool under open-air condition. However, the key problem ahead of practical usage of CT-based SERS technology is how to effectively improve the sensitivity. Herein, a novel SERS platform was first specially designed through electrochemical deposition of graphene onto TiO2 nanoarrays (EG-TiO2). The developed EG-TiO2 SERS platform possessed remarkable Raman activity using copper phthalocyanine (CuPc) as a probe molecule. Taking advantage of a marked Raman response of the CuPc molecule on the EG-TiO2 nanocomposite surface as well as specific recognition of CuPc toward multiple telomeric G-quadruplex, EG-TiO2 nanocomposites were tactfully employed as the SERS substrate for selective and ultrasensitive determination of telomerase activity, with a low detection limit down to 2.07 × 10-16 IU. The present SERS biosensor with high analytical performance, such as high selectivity and sensitivity, has been further explored to determine telomerase activity in stem cells as well as to count the cell numbers. More importantly, using this useful tool, it was discovered that telomerase activity plays an important role in the proliferation and differentiation from human mesenchymal stem cells to neural stem cells. After that, a novel ternary heterostructures SERS substrate, Fe3O4@GO@TiO2, with a significant enhancement factor of 8.08×106 was synthesized. The remarkable enhanced effect of SERS signal was discovered to be attributed to the resonance effect of CuPc, CT between GO and TiO2 and enrichment from porous TiO2 shell. Furthermore, a robust SERS probe with good recyclability under visible light illumination was developed on Fe3O4@GO@TiO2 nanocomposites, toward ultrasensitive detection of cancer cells down to 3 cells. Meanwhile, this probe was successfully applied for in-situ quantification and imaging of PD-L1 on TNBCs surface at single-cell level and monitoring the expression variation of PD-L1 during drug treatment. This work has not only established an approach for gaining fundamental insights into the chemical mechanism (CM) of Raman enhancement but also has opened a new way in the investigation of long-term dynamics of stem cell differentiation and clinical drug screening.

Resume : Nowadays the most common methods for influenza diagnosis in human are based on immunoassays and PCR technology. In comparison to other methods, PCR technologies are less time-consuming and show higher sensitivity. However, they require isolation of the genetic material, which may lead to expensive instrumentation needs. Thus, the development of other detection techniques is necessary. The combination of analytical devices composed of biological sensing elements with electrochemical techniques results in electrochemical biosensors which provide both sensitivity and selectivity. In this study, we present biomolecular mechanisms of influenza virus detection depending on the boron-doped diamond substrate shape. The recognition of the virus biomolecules was based on the interactions between an antibody (anti-M1 antibodies (aM1)) and antigen (virus protein (M1)). Thus, the surfaces of the boron-doped diamond (BDD) and nanocrystalline boron-doped diamond (BNCD) were functionalized with aM1 antibodies for M1 detection. The quantity of adsorbed M1 protein was measured by using the electrochemical impedance spectroscopy technique. As a result, we obtained highly sensitive and specified electrochemical biosensors. We achieved a limit of detection for M1 biomarker in saliva buffer equal to 1 fg ml-1 and 50 fg ml-1 concentration level for BDD-aM1 and BCNW-aM1, respectively. Moreover, our systems exhibit extreme repeatability, short time of response and wide potential window [1,2]. References [1] K. Siuzdak et al., Sensors Actuators, B Chem., 280, 263–271 (2019). [2] D. Nidzworski et al., Sci. Rep., 7, 1–10 (2017). Acknowledgement The authors gratefully acknowledge financial support from the Polish National Science Centre (NCN) under Grant No. 2016/21/B/ST7/01430, 2016/22/E/ST7/00102, 2014/14/M/ST5/00715 and National Centre for Science and Development Grant Techmatstrateg No. 347324 2015/16/T/ST7/00469. This work was partially supported by the Science for Peace Programme of NATO (Grant no. G5147). The DS funds of the Faculty of Electronics, Telecommunications and Informatics of the Gdansk University of Technology are also acknowledged.

Resume : Graphene, a one atom thick layer of graphite, has been studied in variety of research fields including electrochemical devices such as secondary battery and electrocatalytic electrodes. Their unique properties has been caused due to an ideal atomic structure. In particular, it is known that the edge states of graphene has been paid great attentions for more electrochemical active than that in bulk. To discuss their electrochemical behavior quantitatively, it is required to analyze them by a spatially resolved electrochemical characterization. Scanning electrochemical cell microscopy (SECCM) with a nanopipette filled with electrolyte and a reference electrode has been self-assembled and applied to graphene in confined area. The confined area is created through a meniscus as a nanoscale electrochemical cell when the pipette approached to the sample surface. In this talk, we will discuss and visualized their electrochemical activities with variety of structure such as edge/basal plane, the number of layers and folded structures of graphene.

Resume : Increasing demands for renewable energy have attracted numerous studies for the development of low cost and efficient technologies that can highly convert chemical energy storage into usable electricity. Electrochemical energy conversion based on oxygen reduction reaction (ORR) received great interest in the development of fuel cell and metal-air battery technologies. Due to the sluggish kinetics of ORR, noble metal catalysts were used. However, it is desirable to develop highly active catalysts from cheap and abundant materials. In this context, electrochemistry and material science play an essential role. In the present communication, we will present our recent works on the development of carbocatalysts for ORR. The synthesis of doped carbon dots (CDs) were performed in ionic liquid, 1-ethyl-3-methylimidazolium ethylsulfate, using the microwave assisted solvo-thermal method. The generated carbon materials were characterized by several surface sensitive techniques. The as-prepared CDs display a nanometer size particles and N-doping with the presence of thin layer of the ionic liquid. The electrocatalytic activity of the CDs toward the oxygen reduction reaction was investigated. The mechanism of ORR in the presence of CDs was investigated. Interestingly, the CDs generated from glucose/ionic liquid display a selective two-electron oxygen reduction with a high efficiency of hydrogen peroxide production. Furthermore, the role of the surface functionalization that can tune the properties of the catalysts, and the medium (such as immobilized polymer ionic liquids) will be investigated.

Resume : One-dimensional nanomaterials can offer large surface area, facile strain relaxation upon cycling and efficient electron transport pathway to achieve high electrochemical performance. Hence, nanowires have attracted increasing interest in energy related fields. We designed the single nanowire electrochemical device for in situ probing the direct relationship between electrical transport, structure, and electrochemical properties of the single nanowire electrode to understand intrinsic reason of capacity fading. The results show that during the electrochemical reaction, conductivity of the nanowire electrode decreased, which limits the cycle life of the devices. We have developed a facile and high-yield strategy for the oriented formation of CNTs from metal?organic frameworks (MOFs). The appropriate graphitic N doping and the confined metal nanoparticles in CNTs both increase the densities of states near the Fermi level and reduce the work function, hence efficiently enhancing its oxygen reduction activity. We also identified the exciting electrochemical properties (including high electric conductivity, small volume change and self-preserving effect) and superior sodium storage performance of alkaline earth metal vanadates through preparing CaV4O9 nanowires. Furthermore, a novel assembled nanoarchitecture was also presented, which consists of V2O3 nanoparticles embedded in amorphous carbon nanotubes that are then coassembled within a reduced graphene oxide network. The naturally integrated advantages of each subunit exhibit highly stable and ultrafast sodium-ion storage. Our work presented here can inspire new thought in constructing novel one-dimensional structures and accelerate the development of energy storage applications.

Resume : In the last decade, 3D-printing, or additive manufacturing, has become an increasingly popular technique in both industrial and academic research laboratories. 3D-printing allows the user to create a 3-dimensional structure through a layer by layer deposition process controlled by a Computer Aided Design (CAD) software, a 3D-scanner or photogrammetry.1 3D¬-printing is a diverse manufacturing technology as various precursor materials can be used. To date, 3D-printing technologies have been implemented across a wide range of applications from medical devices to producing tools on board the International Space Station (ISS). Electrochemistry is another topical area were 3D-printing can be applied; from the manufacturing of inert electrochemical cells to the production of conductive electrodes for a wide range of applications. Of particular note are various electrochemical energy applications such as the Hydrogen Evolution Reaction (HER) and the Oxygen Reduction Reaction (ORR). Currently, a significant amount of research is currently being undertaken using a cheap commercial carbon based filament called ‘Black Magic’. This work presented herein focuses on the manufacturing and utilisation of 3D-printed electrodes for electrochemical energy applications using ‘Black Magic’. The fabrication, activation and characterisation of our 3D printed ‘Black Magic’ electrodes will be reported, as well as the performance of these carbon based electrodes towards electrochemical energy reactions such as the HER and ORR.2 References: 1. A. Ambrosi and M. Pumera, Chemical Society Reviews, 2016, 45, 2740-2755. 2. M. P. Browne, F. Novotný, Z. Sofer and M. Pumera, ACS Applied Materials & Interfaces, 2018, 10, 40294-40301.

Resume : The large-scale implementation of electrochemical hydrogen production requires several fundamental and practical issues to be solved, especially understanding its mechanism and mass-producing inexpensive electrocatalysts that work well at large current densities. Here we address these challenges by exploring the roles of surface chemistry, and mass-producing inexpensive and efficient electrocatalysts for hydrogen evolution. Up to now (01/15/2019), this project is still underway to make everything done. Three model electrocatalysts, i.e., Cu foam, molybdenum disulfide nanoflakes, molybdenum disulfide nanoflakes modified by carbide nanoparticles will be used. Molybdenum disulfide nanoflakes have been prepared by a self-developing grinding exfoliation technology that uses micro-particles as intermediaries to distribute an applied compressive force into a multitude of smaller shear friction forces that induce exfoliation. This can be achieved with yield of ~ 60 %, one of the highest values reported to date, whereas the production rate of 1.73 g h-1. A set of equipment with a footprint of several square meters should allow annual production exceeding 10 tons to meet the industrial demand. We conjecture that molybdenum disulfide nanoflakes modified by carbide nanoparticles will show the best performance among these 3 electrocatalysts. By combining the surface chemistry and mass-production, our work can not only guide rational design but industrial usage of electrocatalysts that work well at large current densities.

Resume : Effective and low cost catalysts for Oxygen reduction reaction (ORR) constitute a challenge for the commercialisation of low temperature based fuel cell devices (FCs). Platinum and its alloys are the state-of-the-art catalysts, however Pt is expensive and non-ORR selective so it represents the bottleneck for FC commercialisation. Nitrogen doped carbon based electrodes (Nelec) can be considered as a sustainable route to the fabrication of low-cost ORR catalysts due to their intrinsic activity in acid and alkaline environment. The mechanism, the role of different N-sites in ORR and their stability and activity at low pH values are still under debate, as well as the influence of the surface morphology on the catalysis. We discuss a mechanistic study of the ORR activity of model Nelec in a wide ranges of pH. Model Nelec were prepared via sputter deposition and thermal treatment to obtain reproducible and smooth topography, low porosity and tunable N-content and N-site type. The variation of the ORR onset vs pH is correlated to carbon electrode composition by using voltammetric studies between pH 1-13. The role of the carbon scaffold nanostructuring was also studied and correlated to the ORR activity by employing XPS and Raman spectroscopy. This allows to identify (a) optimal characteristics for ORR-active Nelec over a wide pH range, and (b) evidence for a transition in the role of specific N-sites in the determination of onset potential trends.

Resume : One of promising renewable energy, hydrogen, can be generated from electrolysis but the price of efficient electrodes (Pt group metals) are still expensive. For efficient electrolysis without novel materials, carbon is representative among the alternative materials, which have outstanding mechanical and electro-catalytic characteristics. Carbon cloth is one of carbon electrode substrate but its low conductivity is a big obstacle for hydrogen evolution reaction (HER). To make up for low conductivity of carbon cloth, the high electrical conductivity of graphene and the large amount of active sites in MoS2 was synthesized on carbon cloth in the shape of grape. As the result, graphene@MoS2 on carbon cloth has not only larger electro chemical active surface area(ECSA) than the carbon cloth, but also the low onset potential(110mV) and tafel slope(53mV/dec) as electro-catalytic activities compared with MoS2 on carbon cloth(251mV, 185mV/dec) and graphene on carbon cloth(140mV, 116mV/dec). MoS2 /graphene on carbon cloth with long term stability can be used as the efficient HER electrode for electrolysis in the near future. This research was supported by the Nano•Material Technology Development Programthrough the National Research Foundation of Korea (NRF), funded by the Ministry of Science and ICT (2016M3A7B4904328).

Resume : Graphene Oxide Liquid Crystal (GOLC) is a newly emerging graphene based material that exhibits nematic type colloidal discotic liquid crystallinity with the orientational ordering of graphene oxide flakes in good solvents, including water. Since our first discovery of GOLC in aqueous dispersion in 2009, this interesting mesophase has been utilized over world-wide for many different application fields, such as liquid crystalline graphene fiber spinning, highly ordered graphene membrane/film production, porous graphene based materials, prototype liquid crystal display and so on. Interestingly, GOLC also allow us a valuable opportunity for the highly ordered molecular scale assembly of functional nanoscale structures. This presentation will introduce our current status of GOLC research particularly focusing on the nanoscale assembly of functional nanostructures. Besides, relevant research works associated to the nanoscale assembly and chemical modification of various nanoscale graphene based materials will be presented.

Resume : Recently, electrochemiluminesence nanoprobes (ECL NPs) have shown great promise in the area of cancer biomarker monitoring due to their unparalleled signal enhance and high sensitivity. Based on this, here, we for the first time fabricated a high-efficiency ECL NPs - C-Au-luminol nanospheres (C-Au-Lum NSs) assembled aptasensor for target detection. C-Au-lum NSs were synthesized through luminol-reduced Au nanoparticles in the nanoporous of carbon spheres. Under this circumstance, the large surface area coupled with the well-defined special nanostructures of porous walls and hollow interiors of carbon spheres not only highly oriented guide the Au-lum in situ production, but effectively improved the luminophores? dispersity and amount. The novel C-Au-lum NSs materials show high electrochemiluminescence intensity, fast response and good stability while hydrogen peroxide as the coreactant. Meanwhile, the dual signal amplification strategy based on enzymatic circulation and strand displacement was employed to further increase the responsiveness of ECL aptasensor. The construction of ?signal on? ECL aptasensor for the detection of target biomarker Mucin1 (MUC1) which is existed in human breast cancer with ultra-high sensitivity, excellent selectivity and reproducibility. The facile approach may provide new ideas for preparation of energetic ECL NPs with desired nanostructure for numerous applications.

Resume : Two-dimensional (2D) molybdenum sulfide (MoS2) is an attractive noble-metal-free electrocatalyst for the hydrogen evolution (HER) in acids. Tremendous effort has been made to engineer MoS2 catalysts with either more active sites or higher conductivities to enhance their HER activity. However, little attention has been paid to structural and electronic modulations of MoS2 synergistically. Moreover, the Hads energies for most of MoS2 based catalysts have not been well-clarified so far. On the other hand, novel functional carbon-based supports are crucial for the construction of highly efficient and binder-free electrocatalysts for hydrogen evolution. Integrating functional carbon materials with transition metal or transition metal compounds optimizes the hydrogen adsorption energy (Hads) through changing the electronic structures after the formation of C-M (label as transition metal) bond. Herein, 2D hydrogenated graphene (HG) was introduced as the support of MoS2 nanosheets for the construction of MoS2/HG hybrid catalysts. During a simple solvothermal synthesis process, the weight-ratios of MoS2 to HG and the morphology of MoS2 were controlled. The optimized MoS2/HG hybrid catalysts characterized using scanning microscopy and transmission electron microscopy showed that vertical MoS2 ultrathin nansheets arrays are highly ordered and uniformly distributed on the surface of HG. Wrinkled MoS2 nanosheets are interconnected with each other, leading to the formation of a porous structure. The characteristic bonds of C-Mo were observed in Raman spectrum. These unique structure characteristics make vertically aligned MoS2 nanosheets feature more accessible catalytic active sites and ultrafast electron transfer from the HG substrate to the MoS2 edges within one S-Mo-S layer. To gain further the idea about the electronic structures of MoS2 on HG and the Hads energy of the optimized hybrid catalysts, Density Functional Theory (DFT) calculations were conducted. The simulation results confirmed the improvement of the content of Hads on MoS2 by the adequate ferromagnetism of HG support as well as the optimized electronic structure (the enhanced active sites) from C-Mo bonds at the interface of MoS2 and HG. These structure characteristics, electronic properties and moderate hydrogen adsorption energy contribute to the excellent HER performance achieved on the optimized MoS2/HG hybrid catalyst. A low overpotential of 124 mV at the current density of 10 mA cm?2 and a small Tafel slope of 41 mV dec?1 have been achieved together with long-term durability for 24 h continuous operation at 30 mA cm?2 and without observable fading. This strategy paves a way to design and develop other highly efficient, stable, and noble metal-free HER electrocatalysts. Reference 1. Xiuxiu Han, Xili Tong, Xingchen Liu, Xiaodong Wen, Xiang-Yun Guo, and Nianjun Yang. ?Hydrogen Evolution Reaction on Hybrid Catalysts of Vertical MoS2 Nanosheets and Hydrogenated Graphene?. ACS Catal. 2018, 8, 1828-1836.

Resume : Bisphenol (BPA) is an environmental endocrine disruptor and has been listed as one of the priority pollutants in many countries. Recently, photoelectrocatalytic (PEC) is considered as an efficient way for removal of BPA in water. Therefore, this study proposed an efficient PEC interface by decorating the carbon quantum dots (CQDs) on {001} TiO2/Ti photoelectrodes (3D CQDs-{001} TiO2/Ti). The {001} TiO2/Ti were prepared by directly growing the {001} TiO2 with nearly 100 % {001} exposure on a 3D Ti mesh substrate through a simple hydrothermal method, and then the CQDs were closely attached to the {001} facets by a simple hydrothermal method. With respect to the pure {001}TiO2/Ti photoelectrode, the PEC properties under UV-visible irradiation showed that the 3D CQDs-{001}TiO2/Ti photoelectrode displayed the higher photocurrent density values (1.53 times), carrier density (ND) values (2.13 times), and photoelectron lifetime (1.96 times). When BPA (1 mg/L) was treated with two photoelectric anodes under visible irradiation, only 30% BPA removal efficiency was obtained on the{001}TiO2/Ti in 1.5h due to the adsorption. However, there was nearly 95% BPA removal efficiency achieved on the 3D CQDs-{001} TiO2/Ti, indicating the greatly promoted PEC oxidation activity. This mainly depends on the following two aspects. One is the nearly 100% exposed {001} facets obtained on 3D CQDs-{001} TiO2/Ti, which provide the enhanced PEC activity. The other is the outstanding up-converted effect of the CQDs, which can convert visible-light radiation into UV light fluorescence to excite {001} TiO2. In addition, the synergistic effect of powerful energy transfers between {001} TiO2 and the CQDs is key for acquiring enhanced visible-light PEC activity.

Resume : Over the decades, widespread advances have been achieved on nanochannels, including nanochannel-based DNA sequencing, single-molecule detection, smart sensors, and energy transfer and storage. However, most interest has been focused on the contribution from the functional elements (FEs) at the inner wall (IW) of nanochannels, whereas little attention has been paid to the contribution from the FEs at the nanochannels’ outer surface (OS). Herein, we achieve explicit partition of FEOS and FEIW based on accurate regional-modification of OSand IW. The FEIW are served for ionic gating, and the chosen FEOS (hydrophobic or charged)are served for blocking interference molecules into the nanochannels, decreasing the falsesignals for the ionic gating in complex environments. Furthermore, we define a compositefactor, areas of a radar map, to evaluate the FEOS performance for blocking interferencemolecules.