Hybrid materials engineering in biology, chemistry and physics

Resume : Self-healing materials based on reversible crosslink-formation in polymeric matrices became a major research area in materials chemistry in recent years. In this report we present self-healing hybrid inorganic-organic nanocomposites based on thermoreversible Diels-Alder (DA) reactions. Silica as well as magnetite nanoparticles were surface-functionalized with dienes or dienophiles. These particles crosslink and decrosslink a polymer matrix containing the counterpart functional groups at temperatures of approx. 60°C and 120°C, respectively. It can be shown that the density of the functional groups on the surface is a crucial parameter to obtain good crosslinking behavior. Dienes or dienophils which are located just above the surface separated by small spacer groups require enough space to undergo DA reactions. The density of functional groups on the nanoparticle surface can be increased by grafting-from polymerization of polymers containing the necessary groups. This results in core-shell nanoparticles that are able to act as multicomponent crosslinkers in the self-healing matrix. Magnetite based nanocomposites can be heated to reach the crosslinking/decrosslinking temperatures by alternating magnetic fields. Finally, we were able to show that the self-healing mechanism in these materials is reproducible and we could prove that the mechanical properties of the nanocomposites after healing are similar to those of the original materials.

Resume : Magnetic iron-based oxide embedded within a polymer matrix has wide potential application, for instance as magnetic absorbent. Various concentrations of magnetic materials up to 50 wt% have to be considered in order to reach the highest magnetic permeability levels. Meanwhile, the mechanic properties have to be preserved and the permittivity has to be controlled. For this purpose, we have undertaken the elaboration of polymer/magnetic oxide materials using a grafting from method. Non aggregated iron oxide nanoparticles were obtained by thermal decomposition. An atom transfer radical polymerization (ATRP) initiator was covalently grafted onto the oxide surface. Then, monomer (styrene or methyl methacrylate) was polymerized from the initiator-grafted nanoparticles to obtain the hybrid material. Nanoparticles were well dispersed in the polymer as shown by transmission electron microscopy. Small angle X-ray scattering (SAXS) measurements and small angle neutron scattering (SANS) were used to characterize the oxide core and the polymer shell respectively. The oxide core size measured by SAXS was equal to 6-8 nm, in consistency with dynamic light scattering and transmission electron microscopy measurements. The investigations by SANS of the about 30 nm dry diameter nanoparticle shell showed that the morphology of polymer chain as a function of the distance to the iron oxide core can be accurately described by the model initially proposed by Cotton and Daoud for star polymers. Moreover, the rheological behavior of hybrid material was studied in the molten state of the polymer and the variations of storage and loss moduli as a function of frequency also follow the typical behavior of star polymers.

Resume : Natural materials consisting of protein structures impregnated with a tiny amount of metals often exhibit impressive mechanical behavior, which represents a new design paradigm for the development of biomimetic materials. However, due to the absence of proper synthetic methods and the scanty information on the structure of the natural materials, the materialization has still remained a longstanding challenge. Here, by applying a modified Al2O3 atomic layer deposition process to the dragline silk of Nephila pilipes spider, we produced Al-infiltrated silks, which showed unusual mechanical properties. The deformation behavior of the molecular structure of the Al-infiltrated silk has been investigated performing in-situ Raman spectroscopy, where Raman shifts were measured concurrently with macroscopic mechanical deformations. For identifying the role of the infiltrated Al atoms, the study has been performed in parallel with untreated silk and the results have been compared. We found that the infiltrated Al induce serious changes to the hydrogen bondings interconnecting the protein structures of the silk, resulting in the size reduction of the β-sheet crystals. Our experimental results revealed that superior mechanical properties of the Al-infiltrated silk are likely to be caused by the alterations of the sizes of the β-sheet crystals and their distributions.

Resume : Recently there has been a surge of interest in reducing the demand for fossil fuels by developing alternative renewable energy technologies. Thermoelectric materials are useful in converting waste heat to useable electrical energy. However, while thermoelectric materials based on inorganic semiconductors show the high efficieny, they are very expensive, brittle and chemically unstable under ambient condition. Therefore, it is useful to investigate more flexible and stable sources of thermoelectric power. In this study, we present the flexible and chemically stable thermoelectric materials based on nanocarbon (reduced graphene oxide)/Te nanowires composites. Te nanowire (TeNW) was selected due to its high thermopower from 1D quantum confinement effect and easy production of solution process. Nanocarbon such as reduced graphene oxide (rGO) plays an important role to give a good electrical conductivity and stable and flexible frame for composites. TeNWs coated with PEDOT:PSS were mixed with graphene oxides and their hybrid films were prepared by vacuum filtration. By controlling the reduction of the hybrid film by chemical reductant, the electrical and thermoelectric properties of hybrid films were characterized. The morphology of hybrid film was characterized using TEM and SEM. The hybrid film shows the improved thermoelectric efficiency due to the energy filtering effect on the interfaces between rGO and PEDOT:PSS-TeNW.

Resume : Control entry into the pores and subsequent release of biologically active compounds can be carried out by design of the functionality of the pore walls and exterior surface of mesoporous silica lined with the reactive silanol groups. In the present work, we propose the approach for synthesis of pH-sensitive amino-containing nanovalves located near the entrances into the pores at the external surface of MCM-41 silica. Selective chemical functionalization of mesoporous silica particles with ionizable N-(2-aminoethyl)-3-aminopropyl (AEAP) or N-[N'-(N'-phenyl)-2-aminophenyl]-3-aminopropyl (PAPAP) groups was performed by combination of sol-gel condensation and postsynthetic chemical modification. The results of X-ray diffraction and low-temperature ad-desorption of nitrogen indicate that immobilization of AEAP or PAPAP groups on the outer surface of silica particles does not change mesoporous structure of initial silicas. Release properties of MCM-41-type mesoporous silicas selectively modified with AEAP or PAPAP groups were studied for para-aminobenzoic acid. It was found that localization of blocking groups near by pore orifices provides preservation of high loading capacity of carriers and controlled liberation of biologically active compound at pH change. Blocking of pore openings arising from interactions between closely attached amino-containing functional groups of carrier at pH = 6.86 leads to the prevention of para-aminobenzoic acid release, whereas at pH = 1.00 repulsion of protonated amino groups provides unhindered extraction of aromatic amino acid from its mesoporous channels.

Resume : Due to polysulfone (PSf) is extensively used in blood purification applications (such as artificial kidney dialysis). This study uses the strategy of hydrophilic the surface of a material, which can predict and sift out its compositions, calculate the properties of interface, and predict the contact angle by using the molecule design technology. We also develop a new HAR-b-(mPEG) polymer of a hydrophilic molecule fiber structure which has a highly aromatic main chain section for increasing the compatibility with the polysulfone material. After the surface property of a new material is established and the compatibility with the polysulfone material is calculated by simulation, the results are obtained which shows: (1) the linker structure bonded between the hydrophilic and hydrophobic chains has little impact; (2) the long chain section PEG contributes mainly to the hydrophilic properties of the material; and (3) the compatibility with the polysulfone is decreased when the molecular weight is higher than 880. These features may expose the hydrophilic PEG chain to the surface, so that the effect of repelling the adsorption of protein and platelet is achieved.

Resume : Micro energy-dispersive X-ray fluorescence spectrometry (µ-EDXRF) was performed to evaluate the mineral content of human and bovine dentin treated with a total-etch adhesive (Prime & Bond 2.1® - PB) and a self-etching adhesive (Xeno III® - X). Ten human molars (H) and ten bovine anterior teeth (B) were prepared exposing the dentin, divided at the middle and separated into four groups: HPB (control), HX, BPB and BX. µ-EDXRF data were obtained before and after treatments. Untreated dentin of both substrates was not different in Ca content (p< 0.1503), P content (p< 0.2986) and Ca/P ratio (p< 0.1400). HX and BX specimens showed reduced P content (p< 0.0001 and p< 0.0002), HPB and BPB reduced Ca and P content (p< 0.0001; p< 0.0001) when compared to untreated specimens. The Ca/P ratio was significantly higher in HPB and BPB than in HX and BX (p< 0.0001; p< 0.0080). No statistical differences were found between substrates considering the same adhesive. Untreated dentin showed a homogeneous elemental distribution. After adhesive treatments the surface showed an irregular demineralization pattern.

Resume : Nowadays, rapid and efficient remediation solutions to the polluted water have been arousing considerable attention[1]. Layered double hydroxides (LDHs, MII 1-xMIII x(OH)2]x+ (An-)x/n •mH2O) are composed of charged brucite-like layers of divalent and trivalent metal hydroxides, whose excess positive charge is balanced by anions (often carbonate) in the interlayer [2]. In the present work, for the purpose of combining the unique properties of graphene with LDHs to obtain excellent photocatalyst, we developed a facile and effective one-step coprecipitation approach for synthesis of hybrid composites of ZnCr-LDH/graphene photocatalysts. The results revealed that ZnCr-LDH/graphene composites showed much higher photocatalytic activity in the degradation of RhB under visible light irradiation, as compared with pure ZnCr-LDH, which was attributable to unique hetero-nanostructure of ZnCr-LDH/graphene composites facilitating the transportation and separation of the photogenerated electron-hole pairs and thus the continuous generation of reactive oxygen species. The present finding provides a simple approach to fabricate new types of excellent graphene-based hybrid photocatalysts for pollutant water. Reference [1] Y.J. Zhang, L.C. Liu et al., J. Hazard. Mater. 209-210 (2012) 146-150. [2] C.G. Silva, Y. Bouizi, et al., J. Am. Chem. Soc. 131 (2009) 13833-13839.

Resume : Ionogels are interesting because they combine the macroscopic properties of a material such as stiffness with “microscopic” properties such as catalytic activity. In many cases high surface areas or the functionalization of existing surfaces is useful or even mandatory for proper function of a material. While there are now many protocols available for producing ionogels as such, including ionogels with catalytic, sensing, diagnostic, tailred transport, or luminescent activity, the overwhelming fraction of ionogels is a bulk-like material with very low surface area. A cheap and well-established way of generating moderate surface areas is electrospinning. We will present new data on the electrospinning of ionogels, on the adaptability of the process and on first attempts to transform the electrospun materials into functional materials either by incorporating a functional (that is, metal-containing) ionic liquid or by further chemical transformation of the electrospun ionogel fiber mats.

Resume : Calcium phosphate is a key mineral in biology and biomaterials science. The bioinspired synthesis of calcium phosphates from aqueous solution at near-physiological conditions has attracted tremendous interest because it should be possible to grow biosimilar calcium phosphate/organic hybrid materials that could find use in numerous applications such as bone substitutes or dental repair. In spite of the large body of work that has been published on the topic of bioinspired, polymer-controlled calcium phosphate precipitation the field still lacks a complete atomistic and (supra)molecular understanding of how calcium phosphate nucleation, growth, morphogenesis, and phase selection is governed by a specific set of conditions such as the type, concentration, and molecular weight of the organic or polymeric additive. For example, while there are numerous studies of calcium phosphate formation from bulk aqueous solution, the number of studies on the effects of surfaces and interfaces is fairly low. Moreover, most of these studies focus on the effects of polyanionic crystallization additives and the number of studies on polycationic growth modifiers is still limited, as is the case for investigations of polybetaines and polyampholytes. We therefore focus (i) on the role of surfaces and interfaces and (ii) on the effects of polycations on calcium phosphate mineral formation. The presentation will give an overview over the results obtained from a set of different scaffolds

Resume : The realization of new class of devices, for healthcare, is driven by the development of new hybrid materials that assemble together biological and inorganic nano-sized units. Our aim is to develop a biosensor for DNA exploiting the transport properties of Au nanoparticles (NPs) realized onto a SiO2 surface; in particular our final goal is the detection of a mutation of the KRAS gene for the diagnosis of colorectal cancer. The device measures the change, due to the presence of DNA, of tunnel current flowing through NPs arranged in one-dimensional arrays. This kind of device needs a full control of the SiO2-Au, Au-thiolated DNA and DNA-DNA interface as well as NPs shape and spacing. This work presents the design optimization of the device in terms of NPs density, size, and spacing and preliminary results about their electrical response. In particular, we present the growth characteristics of Au NPs onto SiO2, arranged into arrays of lines of ~100 nm width and ~70 µm length. The array are obtained by e-beam lithography followed by Au thin film sputter deposition, PMMA removal and annealing. By microscopic analyses, we analyze the temperature dependence of the NPs morphological properties and their evolution is described within the mean field nucleation model. As a consequence the full control, by annealing temperature and time, of the NPs characteristics is reached in order to optimize the array electrical detection sensitivity, studied by the conductive-AFM technique.

Resume : The influence of synthesis conditions (type and ratio of chemical precursors, temperature of treatment) on the phase composition and morphology of ferrite powders containing barium hexaferrite has been investigated. The ferrite powders have been synthesized by using sol-gel technique at the various temperatures – 850, 950 and 1050C. The light and atomic force microscopy studies have shown that prepared ferrite powders consist of the particles with size 50-100 nm, which agglomerate into formations with size from 1 to 5 microns. XRD studies have showed that the synthesized powders consist of two phase – Fe2O3 and BaFe12O19 and ratio between these phase depends on the temperature of powder treatment at last stage of synthesis. The measurements of magnetic susceptibility in the temperature range 300-850К also confirm the presence of two phase in prepared ferrite powders and correlate with XRD data. It was found that the using of Fe(NO3)3•9H20 and Ba(NO3)2 (at molar ratio 12:1, respectively) as precursors and the temperature treatment at 950C is the most optimal regime for preparing the ferrite powder with maximal content of BaFe12O19. The ESR spectra for prepared ferrite powders indicate on the total magnetic anisotropy, which includes an internal magnetic anisotropy and shape anisotropy of magnetic particles. The prepared barium hexaferrite powder has been used as a filler for fabrication of epoxy composites for electromagnetic shielding investigations.

Resume : Molecular dynamics (MD) simulation was used to simulate the mechanical properties of the interfaces of polypropylene (PP) and modified polypropylene with the graphene(Gh) in order to explore the interfacial strength between the carbon fiber and PP and modified PP in the experimental observation. First, the structures of PP and modified PP were put on the graphene surface and the simulated-annealing procedure was conducted to obtain the stable interface structures and these structures were further used to evaluate the bonding strength of PP and modified PP with the graphene surface. The degree of crystallinity of the modified PP is significantly improved and higher than that of the pristine PP. Also the mechanical strength by tensile simulation indicated the strength of the modified PP/graphene is higher. Finally, the MD simulation results of PP/Gh and modified PP/Gh hybrid obtained in this research are consistence with experimental data.

Resume : Layered tetravalent metal organophosphonates represent an important group of inorganic-organic hybrid compounds due to their excellent stability and the possibility to modify the organic part of these compounds with functional groups. Among them, zirconium phosphonates were the most thoroughly investigated, less attention has been paid to cerium phosphonates. Cerium(IV) phenylphosphonate was prepared by reaction of cerium sulfate or ammonium cerium nitrate with phenylphosphonic acid at various conditions. Three types of compounds were obtained. A yellow hydrated compound with a basal spacing of 15.5 Å was prepared by precipitation at room temperature. A white anhydrous compound with basal spacing of about 14.8 Å was prepared using a hydrothermal synthesis at 100°C or by solid state reaction. Another anhydrous compound with a basal spacing of 15.6 Å was formed by a hydrothermal treatment at 180°C. New functionalized layered cerium phenylphosphonates were prepared by reaction of cerium salt with corresponding phosphonic acid (4-carboxyphenylphosphonic, 4-sulfamoylphenylphosphonic, 1,4-benzenediphosphonic, and 4-sulfophenylphosphonic acid). The compounds prepared were characterized by EDX, elemental analysis, TGA and powder X-ray diffraction. This work was supported by Czech Science Foundation (grant no. 14-13368S).

Resume : Organic pi-conjugated compounds are of interest for a wide scientific community due to their unique properties. These properties can be enhanced by incorporation of these compounds into an interlayer space of layered hosts. Materials prepared in such a way have the advantage, relative to organic compounds, of improved rigidity and thermal stability. In this contribution we describe intercalation of tris(4-(pyridin-4-yl)phenyl)amine (TPPA) into alpha-modification of zirconium phosphate (ZrP) and into zirconium 4 sulfophenylphosphonate (ZrSPP). The formulas of these compounds might be written as Zr(HPO4)2•0.21TPPA•2.5H2O and Zr(HO3SC6H4PO3)1.3(C6H4PO3)0.7•0.35TPPA•2.5H2O. The interlayer distance of the ZrP•TPPA intercalate is 18.52 Å and the interlayer distance in the ZrSPP•TPPA intercalate is 33.2 Å. From the enlargement of the interlayer distance after intercalation we can presume that the TPPA molecules are oriented perpendicularly to the host layers of ZrSPP and slightly tilted to the layers of ZrP. The way of interaction between the host material and the intercalated TPPA molecules was studied by infrared and UV-vis spectra. This work was supported by Czech Science Foundation (grant no. 13-01061S).

Resume : The growth of low-dimensional Prussian blue analogues (PBA) network between magnetic metal hydroxide layers is particularly attracting to study the influences of confinement or dimensionality on the properties of PBA. Insertion of PBA was already reported as weakly bonded counter anions into double layered hydroxides.[1] Insertion of PBA into layered simple hydroxides (LSH) leads to different reactivity. We attempted to insert potassium or sodium hexacyanoferrate(II) into cobalt or copper hydroxyacetate. We will detail here how such a reaction led, unexpectedly, to the direct formation of PBA nano-platelets, the layered hydroxide serving as a metal ion reservoir. The lamellar structure of the starting LSH transforms to PBA platelets via a pseudomorphic transformation.[2] All products were characterized by PXRD, SEM, TEM and magnetic measurements, completed by XPS and Mössbauer spectroscopy.[3] Finally, replacing the acetates by metal complexes in the starting compound allows for different reactivity and different products. [1] a) I. Carpani et al., J. Solid State Chem. 179, 3981-3988 (2006); b) H. S. Panda et al., J. Phys. Chem. C 113, 9560-9567 (2009); c) G. Layrac, et al., J. Phys. Chem. C 115, 3263-3271 (2011); E. Coronado, et al., Inorg. Chem., 2010, 49, 1313. [2] J. Reboul, et al., Nat Mater 11, 717-723 (2012). [3] M. Lang, E. Delahaye, D. Ihiawakrim, O. Ersen, D. Foix, J.M. Grenèche, G. Rogez, P. Rabu, in preparation.

Resume : Layered Double Hydroxides (LDH) are lamellar solids defined by the general formula [M2+1-xM3+x(OH)2]x+ [(An-)x/n, y H2O]. Electroactive cations (Ni, Co) present in the layer structure and/or intercalated redox active anions, i.e. 2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulphonate (ABTS), can confer to these materials specific electrochemical properties. ZnCr-ABTS LDH has already been studied for enzyme immobilization to elaborate biosensors and biofuel cells. The presence of ABTS species into the interlayer domain allows electron transfer between the immobilized laccase and the electrode. In this study, we have synthesized CoAl-ABTS hybrid LDH to combine intralayer electronic transfer due to Co redox species with the interlayer electronic transfer assumed by the presence of ABTS. The improvement of electronic transfer between the LDH particles was also studied by addition of graphene in the system. CoAl-ABTS and CoAl-ABTS@graphene composite were prepared by in situ coprecipitation. The as-obtained materials were then fully characterized by means of XRD, FTIR, Raman spectroscopy, Cyclic Voltammetry and Electrochemical Impedance Spectroscopy to better understand the entire electronic phenomenon that takes place in this composite material. Their application as electrode material for bioanode and biocathode in a lactate/O2 enzymatic biofuel cell was also investigated. Their use as a biocathode exhibits a response 5 times higher than that of ZnCr-LDH for O2 reduction catalysis.

Resume : A series of layered double hydroxides interleaved with surfactant using saturated alkyl chain carboxylate anions CH3(CH2)mCOOH, even number 6 ≤ m ≤ 16, obtained by coprecipitation method was dispersed by melt polymer extrusion into polypropylene (PP), poly(butylene)succinate (PBS) and polydimethylsiloxane (PDMS). First the hybrid LDH materials were investigated by means of X-ray diffraction and Fourier transform IR spectroscopy resulting in the presence of contracted basal spacing over the entire variation of m. Dispersion into polymer yields for all of them intermixed polymer structures, but the rheological behavior is function of the polymer. For PP longer alkyl chain induces a a reinforcement while smaller one induces a plasticizing effect, and for PBS and PDMS a chain-extender-type behavior is observed for the all series. The relative change of viscosity from frequency sweep stress linear response is visualized by Cole Cole plot. The molecular weight change relative to polymer free of filler and obtained from the power-law of the zero-shear viscosity is found to be linearly dependent of the basal spacing increase. Such cross-study using XRD and melt polymer rheology is able to unravel the attritive or plastizicing role of the organoclay as function of the basal spacing expansion, and to respond whether LDH interleaved platelets are of interest for polar and non-polar polymer and finally to predictively monitor the interfacial attrition through surfactant modified LDH.

Resume : Transition metal Layered Simple Hydroxides (LSH) are particularly well suited to grafting reactions of various organic molecules.[1] However, a major drawback of the functionalization reactions of layered hydroxides lies in the fact that they proceed by anion-exchange reaction, especially effective in aqueous medium. This severely limits the type of molecules that can be considered to be grafted in the interlamellar space. To overcome this difficulty, one solution is to synthesize in situ the desired molecules from a pre-grafted functional precursor.[2] Thus, only the first stage (grafting the precursor) requires the use of insertion-grafting conditions by anion exchange. The following reactions may use a much larger panel of conditions, including the use of non-aqueous solvents. We report in this presentation the post-synthesis modification of a Co LSH, functionalized with p-amino-benzoic acid. We show that the amine groups react in situ with various aldehydes to form imines. Interestingly, conventional activation (heating) is inefficient in the present case, whereas microwave irradiation enables the in situ reaction. This technique constitutes a new appealing strategy for functionalization of layered structures.[3] [1] G. Rogez et al., Chem. Soc. Rev. 40, 1031-1058 (2011). [2] S. S. Y. Chui et al., Science 283, 1148-1150 (1999). [3] O. Palamarciuc et al., New J. Chem., DOI: 10.1039/C3NJ01231J (2014).

Resume : We have developed a facile method for the synthesis of poly (allylamine hydrochloride; PAH) polymer assisted and multi-functional groups containing mesoporous calcium silicates (CS-PAH) with a large specific surface area (BET = 348.4 m2g-1) and pore volume (Vp=1.42 cm-3g-1). TEOS was employed as silicon source, which rapidly hydrolyzes and reacts with amine groups of PAH and form spherical nanosheets of Si-PAH, subsequently Ca2 creased furrows in the nanosheets as building blocks in basic media. The obtained highly porous and multifunctional 3D network of CS-PAH containing excess of Ca2 and NH3 enriches the surfaces with huge cationic charges (ζ = 65.66 mV) and results in extremely higher loading of anionic drugs or protein. Ibuprofen (IBU) and FITC labeled bovine albumin (FITC-Albumin) were chosen as a model drug and protein respectively for testing loading and delivery proficiency of CS-PAH. Ultrahigh drug loading capacities (DLC) and their released patterns have been investigated under controlled pH conditions. Strikingly, the highest DLC reported so far (3.6 mg IBU is loaded in per mg carrier) has been achieved in this work. Furthermore, CS-PAH can entirely transform to hydroxyapatite after the drug release in simulated body fluid (SBF), implying the good bioactivity and biodegradability of CS-PAH. Since the CS-PAH drug-delivery system combines the advantages such as large specific surface area, large pore volume, extremely high DLC, adjustable drug-release rate, and great bioactivity, therefore it is promising for reducing systemic side effects.

Resume : The electronic properties of the ScxGa1-xAs ternary alloy and superlattice (SL) systems are investigated within the first principles full potential linear muffin-tin orbitals method (FPLMTO) in its atomic sphere approximation (ASA) coupled to the technique of the empty spheres which enables an accurate treatment of the interstitial regions. It is found that the alloy concentration for which the transition from rock salt (B1) to zinc blende (B3) structure occurs is around x =58.6% and that these systems may have a large semiconducting gap in the zinc blende (B3) phase and that for SLs, this gapis direct at Γ.

Resume : For spintronic components inorganic ferromagnetic oxides like La0.7Sr0.3MnO3 (LSMO) and organic semiconductors form a promising combination of 100% spin polarization and very long spin relaxation length. However, fabrication of hybrids requires high temperature growth in oxygen ambient for LSMO and evaporation or spin coating in vacuum or inert atmosphere for the organics. This requires sample manipulation between both deposition steps and results in contamination (C, O, other impurities) which deteriorate the interface energetics significantly. In this work the growth of the organic semiconductor material performed consecutively after that of the inorganic ferromagnet without changing the processing chamber is investigated. This minimizes the contamination effect and consequently the improved interface properties and spintronic performance are expected. The PLD at 1064 nm, 2 Hz and fluences around 0.18 J/cm2 is used to produce organic semiconductor thin films of Rubrene, a material known for high carrier mobility. The AFM and x-ray reflection data show continuous films in all the grown samples with very small surface roughness. Raman spectra of the 7 nm thin film reveal signature consistent with active modes of the Rubrene molecule. The XPS and magneto-transport studies of interfaces and devices grown under similar condition are currently underway and are expected to lead to improved control over the formation of hybrid interface and novel device performance in near future.

Resume : Hybrid materials based on borate glass matrix and the tris(8-hydroxyquinoline) aluminum, gallium and indium (Mq3 = Alq3, Gaq3 and Inq3) organic phosphors, which are used as light emitting materials in OLED were synthesized by two methods. Bulk hybrid materials (BHM) were synthesized by melting of dried В2О3 and powdered Mq3 (0.02–0.1 wt. %) at temperatures below Mq3 decay during 10-60 minutes in glassy carbon crucibles. Samples were obtained by melt freezing or by pulling of thick fibers. According to XRD analysis the samples were amorphous (glass samples) and were free from visible inclusions and bubbles. Thin-film hybrid materials (TFHM) were made by vacuum thermal sputtering. In the case of 100 to 300 nm TFHM containing ~ 1 vol.% of Mq3 we succeeded to measure photo and electroluminescence. The influence of glass melting parameters on BHM’s spectral properties showed that the synthesis duration increase resulted to a luminescence maximum shift towards shorter wave lengths in comparison with pure crystalline Mq3. The luminescence bandwidths of the synthesized BHM's were considerably larger than that of the initial crystalline Mq3, which might be caused by a presence of a large number of emitting centers of different conformations in BHM's and by the levels splitting by the crystal field of the inorganic matrix.

Resume : Polyvinyl chloride (PVC) is one of the most extensively applied membrane materials in the industry for its robust mechanical strength, low cost, and excellent chemical properties (e.g., acid, alkali, and solvent resistance). However, its hydrophobic nature that often results in severe membrane fouling and decline of permeability, has been a barrier for their application in waste water treatment. Many studies have attempted to improve the hydrophilicity of PVC membranes with various techniques, such as physical blending, chemical grafting and surface modification. Among these methods, blending with inorganic materials is interesting due to its convenient operation and mild condition. Recently, the sol–gel technique has provided new opportunities for the preparation of organic-inorganic hybrid materials. The objective of this work was to systematically reveal the structure, morphology, hydrophilicity, as well as permeability and mechanical properties of the hybrid PVC–SiO2 membranes prepared by sol–gel method. Results showed that silica had been successfully immobilized on the surface of membranes and –OH groups on the SiO2 particles were generated according to the FTIR analysis. SEM pictures showed the morphology of PVC–SiO2 composite membranes changed from cavity structure to finger-like pore structure and asymmetric cross-section structure with increasing SiO2 sol concentration. The hydrophilicity and permeability property of PVC–SiO2 composite membranes were further examined. The addition of SiO2 sol not only intensified the interaction force among PVC macromolecules, but also formed a crosslinking structure between polymeric chains and SiO2 particles, and led to the increase of the mechanical properties.

Resume : A surface treatment with atmospheric pressure plasma is expected in many fields. The reason are as followings; processing is possible in dry environment, generally a processing time is short and most of harmful waste is not exhausted. In recent years not only channeling, hardening and a protection but also sanitization, sterilization have been expected as surface treatment by plasmas. In this study, we developed a new system that UV light source was equipped with by the system, and, as well as plasma, UV light irradiation and ozone can be formed, was which could irradiate a surface with serpentine plasma. Plasma irradiation was carried out for green mold attached to on materials surface, and, using this system, a sanitization effect was investigated. Serpentine plasma is generally called a gliding arc discharge (GAD), however because GAD did not usually have most of characteristics of normal arc discharge, about plasma part, we decided to call it with Serpentine plasma. The construction of our system was atmospheric pressure discharge system with 6 electrodes type, 6 phases commercial AC power supplies were used for. And three low-pressure mercury lamps were equipped with in a discharge tube. This lamp has three roles as a UV light source. One is an effect of discharge voltage drop by the photoelectric effect. Next is an ozone generation effect for a surface. Last one is a UV light irradiation effect to a surface. Using this compound plasma UV irradiation system, we applied green mold to various surface (nutrient medium, fruits, plastics, ceramics) and observed a characteristic change of the mold. As for the plasma irradiation, it was observed appearance at distance from the top of electrodes (5cm ~ 15cm) and irradiation time (3sec ~ 120sec), in all surface materials, a suppressant effect of the mold was confirmed.

Resume : Super-hydrophobicity of solid surfaces is the one of the unique surface properties required in many surface-related applications. In general, super-hydrophobic surfaces have been mostly produced in terms of the following two approaches: (1) the increase in the contact surface area and (2) the decrease in the contact surface energy. Here, we have investigated the surface hydrophobicity of nano-textured films containing either porous or pillar nanostructures with various aspect ratios. To fabricate these kinds of the nano-textured films, first, anodized aluminum oxides (AAOs) with regularly ordered pores, as nano-templates, were fabricated. Then, the textures of the AAO surfaces were changed from a columnar structure to a pillar one, via additional etching AAO walls with different times. Since the resulting AAO surfaces showed highly ordered nanostructures and a hydrophilic surface character, fluorinated self-assembled monolayers were chemically grafted to the AAO surfaces. Additionally, polymer films were manipulated by using molding with AAO nano-templates with a fixed columnar geometry: the polymer nano-textures could be controlled via changing molding pressure and detaching force. All the nano-textured surfaces were characterized by water contact angle, X-ray, and morphological analyses.

Resume : Inverse electron demand Diels-Alder (iEDDA) reactions between 1,2,4,5-tetrazines and alkenes have been applied for the synthesis of pyridazine-based ligands which were used as building blocks in metallopolymers or metal-organic frameworks. More recently, tetrazine-alkene iEDDA reactions were identified to fit the criteria for “click” chemistry reactions and therefore rapidly gained attention in molecular biology as a fast and versatile tool for bioorthogonal conjugation. In these works, mostly highly strained olefins such as trans-cyclooctenes or norbornenes and hydrolytically stable, yet less reactive, tetrazine species are used. However, less reactive dienophiles such as double bonds with a large degree of steric hindrance can be also addressed by using more reactive dienes or applying higher reaction temperatures so that the scope of iEDDA reactions can be extended to material modification. We performed iEDDA reactions with di(pyridyl)-1,2,4,5-tetrazine on the residual double bonds in the polymer backbone of emulsion-templated poly(dicyclopentadiene) (pDCPD) foams which resulted to be a high-yielding (2 mmol pyridazines or 8 mmol N/g), straightforward and versatile single-step method for their post-functionalisation with grafted di(pyridyl)pyridazine ligands bearing different functionalities. Furthermore, the coordination chemistry of these ligands as well as the influence of the performed modifications on mechanical properties have been investigated.

Resume : The single-file transport of microscopic particles, including ions and molecules, through nanofluidic channels has recently attracted much attention for applications of the sensing and manipulation of biomolecules. Tremendous engineering applications utilizing new physics of nanofludic channles have been reported and their basic fundamentals are actively researched mostly using computational simulation. Despite the development of advanced lithographic technology, the fabrication of nanochannel with sub-10nm scale is still challenging. This is why most research on nanofludic channel is conducted using computational simulation. The precise and repeatable control of the channel dimension (typically diameter) is difficult to be achieved at sub-10nm geometry. Moreover, the inner-surface functionalization of nanochannels which are necessarily followed for manipulation of charged particles is also difficult due to extremely tiny entrance of nanochannels. In this poster, I will present the fabrication of sub-10 nm nanochannels by using atomic layer deposition(ALD) with track-etched Polycarbonate membrane(d=~100nm) and AAO template(d=~20nm). The diameter of nanochannel was controlled precisely with self-limiting process of ALD. In addition, the inner-surface functionalization of nanochannels was also achieved by deposition of inorganic thin films(eg. TiO2,) and controlled peptide-surface modification, resulting in functional nanochannels based on organic/inorganic hybrid materials.

Resume : Zn-Al-AG nanohybrid was successfully prepared through urea hydrolysis. XRD pattern of Zn-Al-AG LDH showed new reflections at 2.1 nm, 1.1 nm and 0.7 nm indicating that Zn-Al-AG nanohybrid has been formed through host-guest interaction. These values confirmed that the dye Acid Green1 (AG1) is successfully intercalated inside the layered structure of Zn-Al LDH. Infrared spectrum and thermal analysis indicated that the Acid Green1 (AG1) anions have been intercalated into the interlayer galleries of the LDH. TEM images showed flat plate-like morphology for Zn-Al-AG nano-hybrid and the sheets are aggregated together because of the hydrophobic behavior of organic species. The prepared Zn-Al-AG nanohybrid used as fillers for preparation of polystyrene (PS) nanocomposite film using casting technique with different weight ratios ( 0.125, 0.250 and 0.50 wt% ). The mechanical properties of hybrid polymer nanocomposite films were investigated. The PS/ nanohybrids composite show significant improvement in mechanical properties of the matrix as compared to the neat polymer. The Zn-Al-AG nanohybrid act as a hardener agent for the neat polymer.

Resume : Recently, significant interest is observed in research on hybrid organic-inorganic nanomaterials for biomedical applications. Systems characterized by the unique optical properties of noble metal nanoparticles (NPs) in conjunction with DNA recognition capabilities are investigated. For highly sensitive detection of Hg ions and energy carriers (ATP) the DNA functionalized colloidal Au NPs are successfully demonstrated. In this work we report the design of the plasmonic effect for the case of DNA-based biomedical sensors supported on semi-regular Au nanoarrays. The NPs are produced by means of pulsed laser annealing of ultrathin Au films and reveal spherical shape and also broad size distributions. The characteristic plasmon resonances (PR) of peak positions and halfwidths dependent on the array geometries are strongly damped due to radiative, surface, bulk and interfacial terms. From the observed resonance peak positions below 2.3 eV the nearly constant nonradiative damping is deduced and changes in the PR band due to array geometry variations are assigned to radiative decay. The re-annealing of NP arrays causes almost double broadening and intensity increase of the resonance profile indicating on effective tuning in case of the hybrid DNA-Au nanoarray sensor.

Resume : Ionic liquids (ILs), with their inherent ion conductivity and negligible vapour pressure can be exploited in proton exchange membrane (PEM) fuel cells where thermal management is a major problem and the cell operation temperature is limited by the boiling point of water. In this work, sulfonated poly (ether ether ketone) (SPEEK) membranes were modified by the incorporation of tetrabutyl phosphonium bromide, [(C4H9)4P]+Br- by solvent-casting. Electrochemical impedance spectroscopy (EIS) was used to study the electrical properties of the modified membranes. Simultaneous thermogravimetry (TGA) and Fourier-transform infrared (FTIR) studies allowed evaluating the thermal stability of the modified membranes in terms of their water content. Nuclear magnetic resonance (NMR) technique was applied to study the changes in the chemical environment due to the interaction between the ionic liquid and the polymer. Mechanical properties were studied by Dynamic Mechanical Analysis (DMA). Microstructural changes were observed using scanning electron microscopy (SEM), which revealed increased pore size in the polymer matrix due to the large phosphonium cation. The ion exchange capacity (IEC) of the membranes was observed to increase on IL incorporation due to the low affinity of the hydrophobic phosphonium cation for the sulfonic acid group and hence the availability of more ion exchange sites per gram of the polymer. Keywords: SPEEK, phosphonium, ionic liquid, ion exchange capacity, TGA, FTIR

Resume : In the present work, polymer blends based on Poly (vinyl alchol) (PVA) and Poly acrylic acid (PAA) was prepared with different molar ratios by solvent-casting technique. XRD spectra of the blends show that the degree of crystallinity of PVA starts to decrease with the addition of PAA due to the formation of interpenetrating polymer chain of PAA in PVA membranes. DMA analysis reveals that the storage modulus of 25mol% PAA sample is comparable to pure PVA membrane confirming the mechanical stability of the blend membranes. Tan delta vs. temperature plot of all the blend membranes shows two peaks, corresponding to α-relaxation (62-67°C) and β -relaxation (5-11°C) modes. 1H NMR spectra of pure PVA and PVA-PAA blend membranes shows all the peaks corresponding to OH (4-5ppm), CH (3.8ppm), DMSO (2.5ppm) as well as CH3 (2ppm) and CH2 (1.5ppm) of residual acetate group from hydrolyzed PVA. Significant changes in the peak area and the chemical shift of the PVA hydroxyl signal (4-5ppm) are observed when comparing to pure PVA spectrum revealing the strong intermolecular interactions (hydrogen bonding) between OH group of PVA and PAA. DSC curves of the blend membranes show single Tg indicating that the PVA/PAA blends are miscible in the full range of composition. The effect of doping lithium salt with various anions on the thermal, mechanical and electrochemical properties of these blend membranes are also discussed for its application in lithium ion batteries.Keywords: PVA, PAA, DMA

Resume : While research at the frontier between Chemistry and Biology is of major importance for the design of new drugs, there is also high potential for developing novel materials for biotechnologies. In this context, we will describe how phosphonic acid-mediated modification of inorganic surfaces can be applied to the synthesis of biomaterials. The integration of drugs and devices is a growing force in the medical industry. In this context, a new calcium phosphate cement-based (CPC) medical device will be presented, capable of providing mechanical reinforcement and delivering a bisphosphonate (BP) anti-osteoporotic drug locally. The main properties of the biomaterial are not significantly affected, in terms of injectability and setting time, provided that the BP is chemisorbed as a monolayer onto calcium deficient apatite, one component of the cement. This route allows controlling the drug release under simulated in vivo conditions, and very promising pre-clinical investigation of the cement properties showed the ability of the Alendronate-loaded cement to resorb while promoting new bone formation. In a second example, a new concept for the preparation of artificial antibody microarrays will be described, in which proteic scaffolds are covalently bound to a zirconium phosphonate monolayer through an inorganic linkage, thus allowing controlled orientation of the immobilized probes and highly sensitive detection of antigen targets.

Resume : Calcium carbonate (CaCO3) crystals show wide perspectives as smart carriers for drugs due to their capability to adsorb, and more importantly to entrap, molecules. Moreover, CaCO3 is a biocompatible and biodegradable material, which preparation is easy, low cost, organic solvent-free and the size of the CaCO3 particles can be easily controlled. CaCO3 solubility is pH-sensitive and the use of CaCO3 crystals entrapping molecules allows their release only where the dissolution of crystal occurs. This carrier is particularly suitable for the selective release of drugs in tissues that are more acidic than normal physiological pH (tumors, inflamed tissues). The feasibility of such a system for anticancer therapy was tested in vitro by releasing the drug doxorubicin (DOX), an anthracycline widely used in chemotherapy, from calcite/DOX hybrid crystals. In addition doped calcite hybrid crystals can be used to store efficiently unstable drugs. Minocycline, an anti-inflammatory drug sensitive to light, heat and pH, was incorporated in calcite crystals and its chemical properties remained unchanged for months. In regenerative medicine molecule-doped calcite crystals can be used to create active scaffolds. CaCO3 crystals entrapping retinoic acid (a differentiating agent) were synthesized. In vitro tests demonstrated that the controlled release of retinoic acid via crystal dissolution allowed the differentiation of stem cells into astrocytes.

Resume : The hydrogels of self-assembling ionic complementary peptides have collected in the scientific community increasingly consensus as mimetics of the extracellular matrix that can offer 3D supports for cell growth or be vehicles for the delivery of stem cells or drugs. Such scaffolds have also been proposed as bone substitutes for small defects as they promote beneficial effects on human osteoblasts. In this context, our research deals with the introduction of a layer of self-assembling peptides on a TiO2 surface, whose surface has been previously sandblasted and acid-etched. The layer of the peptide was anchored to the metal oxyde by covalent functionalization with self-assembling sequences. Enrichments of peptide layer has been also proposed with the growth factor IGF- 1, incorporated into the layer, and / or with a conjugate obtained by chemoselective ligation between a self- assembling peptide and a sequence of 25 residues containing 4 GRGDSP motifs per chain. In this work, we present an accurate spectroscopic investigation of the proposed biocompatible system carried out by state-of-the-art synchrotron radiation methodologies: high resolution XPS and angular dependent NEXAFS. HR-XPS studies confirmed the change in the surface composition in agreement with the proposed enrichments, and lead to assess the self-assembling peptide chemical stability. NEXAFS spectra collected in angular dependent mode at the C K-edge allowed to investigate the self-assembling behavior of the macromolecules, as well as to determine their molecular orientation on the substrate.

Resume : Caenorhabditis elegans (C. elegans) is a 1-mm long free-living soil nematode widely used in biomedicine as a model organism. Its key attributes as an experimental system, including its simplicity, transparency, short life cycle, sequenced genome and small body size, together with the ease of cultivation in the lab, make C. elegans a promising animal model to evaluate nanoparticles in vivo. Our objective is to use C. elegans in the primary screening of nanoparticles with biomedical applications within the manufacturing lab, in order to validate their use, to optimize their design, and to study their toxicity. In the present work, we assessed the stability of the iron oxide nanoparticles (SPIONs) in the C. elegans media by Dynamic Light Scattering. The interaction between SPIONs and C. elegans was evaluated by magnetometry, from which we quantified the iron content of worms treated with different concentrations of SPIONs for 24 hours and evaluated the morphology of SPIONs after this time and excreted SPIONs. The localization of SPIONs within the body of the worm was evaluated using Perls’ Prussian blue staining.

Resume : The idea of protect a catalytically active system by embedding it in/anchoring it on it a matrix is the underlying and widely used concept in heterogeneous catalysis. The use of hybrid materials to “heterogenize” catalysts, in particular by the embedding of the catalyst into a polymer matrix, is a fertile field of research. Recently, we have evidenced the possibility to use zirconium-based oxoclusters to activate hydrogen peroxide, for the oxidation of organic substrates. The oxidation of methyl p-tolylsulfide to the corresponding sulfoxide and sulfone was chosen as model reaction, showing an interesting selectivity towards the oxidation of the sulfoxide. Now, we have embedded Zr and Hf oxoclusters into PMMA matrix and proved their effectiveness towards the oxydesulfurization of a model fuel. To this aim, we have exploited such reactivity to perform the oxidation of dibenzothiophene (DBT) to the corresponding sulfoxide (DBTO) and sulfone (DBTO2). Up to 90% yield for DBT conversion was obtained in 24 h, with a 85% selectivity for DBTO2. In most cases, thanks to the enhanced affinity of the polymeric matrix toward polar substrates and solvents, the heterogeneous set-up have shown to be more efficient than the corresponding homogeneous systems, and has allowed the recovery and recycling of the catalytic species. FT-IR, SS-NMR and XAS showed good stability of the hybrids under catalytic conditions. [1] Wight et al. Chem. Rev 2002, 102, 3589 [2] Gross, S. J. Mater. Chem. 2011, 21, 15853

Resume : Asphalt is a sticky viscoelastic petroleum industry by-product, used mostly as aggregates binder in road pavement. Lately, refining strategies are changing and high molecular fractions can be cracked into lighter fuel fractions leading to difficulties in answering the worldwide needs in asphalt. To avoid this problem, some biomass-based binders have been developed. The weak point of those alternative binders is that edible oil is used. Therefore, it has been decided to investigate the potential of microalgae, which do not compete with human feeding. Microalgae are already studied for bioenergy, or animal feeding. For economic and ecological reasons, the by-products resulting from those industries will have to be valorized. Consequently, we propose to study the potential of those by-products as binder for aggregates. Two processes have been studied. First, organic solvents extractions have been performed as an exploratory study. The oil extracted has been characterized from a chemical and a mechanical point of view showing an interesting asphalt-like behaviour. Nevertheless, to reach an economic viability, all fractions of the microalgae need to be valorized. The second study focused on a new promising solvent-free method: the hydrothermal liquefaction. This process allowed recovering around 54 wt.% of a hydrophobic material. By tuning the hydrothermal conditions the bio-crude rheological behavior can be controlled, to reach the one of petroleum bitumen.

Resume : Polymer-based thin films have become more attractive for their advantages of low cost, light weight and easy processability, instead of their limited exciton diffusion length, low electrical conductivity, low charge-carrier mobility, narrow absorption spectrum and low chemical and thermal stability. In our present study we have chosen poly(9-vinylcarbazole) (PVK), a π-conjugated polymer, as an active polymeric material because it is being used as one of the most popular OPV materials during last decade. We report the charge carrier photogeneration of PVK with different weight proportions (0~25 wt%) of a hybride material, consisting of phenethylammonium (PEA)/Vanadium phosphate, using IR, UV-Vis, and energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), steady state photocurrent (SSPC) measurement, and atomic force microscopy (AFM). The SSPC measurements showed that the photocurrent of PVK was reduced by approximately three orders of magnitude by the incorporation of a small amount (~12 wt%) of the hybride material, suggesting that hole transport occurred through the PVK carbazole groups, whereas a reverse trend was observed at high proportions (>12 wt%) of hybride materials, suggesting that transport occurred via hydride molecules. The transition to a trap-controlled hopping mechanism was explained by the difference in ionization potential and electron affinity of the two compounds as well as the formation of charge percolation threshold pathways.

Resume : In this work, we study the evolution of amino group functionalization on porous silicon (PS) by using Fourier Transform infrared spectroscopy (FTIR). Amino-terminated organic layers are deposited on silicon (Si) wafers and incorporated on PS by assembling 3-aminopropyltriethoxylane (APTES) in freshly prepared hydrolysis solution. FTIR spectra of APTES-Si present absorption bands associated to -NH2, -CH2 and -SiO molecules arrangements. FTIR spectrum of APTES-PS presents in addition to the absorption bands associated to APTES presence, absorption peaks associated to SiHx compound between 2000 cm-1 and 2300 cm-1 spectral range. PS layers are initially covered by silicon hydrogen species. By varying the immersion time of PS samples in hydrolyzed APTES solution, the intensity of Si-SiHx absorption bands decreases with the apparition of O-Si-H features. After adequate time, all Si-H absorption bands disappear indicating a total functionalization of PS layer.

Resume : Reports on soft-chemistry hybrid techniques have shown great success in controlling the size and the morphology of oxide nanocrystals used as active materials for gas-sensing devices. In this context, SnO2, ZnO and WO3 nanocrystals with specific exposed surfaces were prepared by colloidal synthesis assisted by capping agents (oleic acid, oleylamine, tetramethylammonium hydroxide) which selectively adsorb on the different surfaces of the crystal, guiding the growth process and allowing to modulate the final shape. In order to suggest a rationale for the relative importance of the crystal faces in the sensing mechanism, the sensing behavior of the nanocrystals toward CO or NH3 was examined and the obtained performances were discussed in connection with the paramagnetic oxygen defects (VO• centers) detected by ESR or with the surface nitrogen species revealed by XPS. Results support the idea that the presence of specific surfaces in SnO2 and ZnO nanocrystals tune the generation of the VO• centers driving their sensing performance toward CO. For WO3, it turned out that definite surfaces represent privileged reactive sites for the NH3 oxidation and therefore are essential for enhancing the sensing properties. These outcomes may help to a more effective evaluation of the involvement of the crystal surfaces in the sensing mechanism and may shed some light on how colloidal hybrid methods can be better applied to design more efficient gas sensors.

Resume : During the last decade, there has been a tremendous interest in Janus particles with more than 1500 papers on this concept dealing with synthesis, production yield, and more recently functionalisation, self-assembly and applications. However, when carefully looking at these reports, it appears that they mainly concern associations between two polymers, a polymer and metal or metal oxide, and a metal with a dielectric metal oxide. Samples based on metal/semiconductors are scarce. Additionally, most of these methods of production are time consuming on the one hand and produce rather low quantities of particles on the other hand, as stressed by their authors. It is seems crucial to implement a technique which circumvent these drawbacks and setup a simple device which allows a facile production of significant amount of Janus nanoparticles. In this context, we present a general and flexible optofluidics strategy in lab-on-chip. The concept consists in activating the band gap of flowing semiconductor nanoparticles by a Laser to generate electron-hole pairs and use electrons to photoactivate the redox transformation of an active ion present in the flowing solution. Nano TiO2 is an oxide of choice due to its extended use, high stability, low cost, and UV activity. Controlled synthesis of TiO2 nanoobjects with various morphologies will be detailed as well as their laser dissymetrisation by metals (Ag, Au) when varying the different parameters of photodeposition in the microchannel:

Resume : Over-lithiated layered oxide (OLO) (Li1.18Ni0.17Co0.1Mn0.56O2) has attracted a lot of interests as a cathode material in high energy density lithium ion batteries for hybrid vehicle and smart grid energy storage systems due to its prominent energy density over 250 mAh g-1. However, the problem of increasing resistance, which is originated from their structural deformations and oxygen evolutions owing to participation of Li2MnO3 to de-lithiation process, restricts wide applications of OLO. We have investigated an innovative hybrid organic-inorganic energy storages material that is surface modification with organic functionality on OLO to improve the cycleability and rate capabilities of OLO, by gas-phase catalytic reaction. This is a simple process and can be easily scalable. Detail surface analyses support that the formation of carbonaceous-coatings on OLO surface without any chemical or physical breakdowns of the oxide cathode structure is achieved. These improvements have great potential since the methodology is compatible with other cathode materials and it will not deteriorate their original crystal structure. The microstructures of the prepared samples are investigated by X-ray diffraction method and secondary electron microscope. Furthermore, the surface modified samples with that 0.1wt.% of carbon in the electrode material confirmed by thermal gravity analysis, is found to exhibit higher conductivity, rate capability and specific discharge capacity than the pristine samples, which are attributed to the suppression of contact resistance and the fast charge transfer reactions as confirmed by EIS analyses.

Resume : SiO2 fillers are commonly used to enhance the rubber mechanical properties. The efficacy depends on size, shape and surface of SiO2 particles which affect the interaction of the filler with rubber. The knowledge of the organic/inorganic interface plays a key role in the control of this interaction; nevertheless its study still remains an open challenge both from the industrial and fundamental points of view. In order to deepen this issue, the work focused on the sol-gel synthesis of SiO2 nanofillers by novel in-situ aqueous and non-aqueous routes and by ex-situ method assisted by capping agents. SiO2 nanoparticles different in size, shape and surface functionalization were designed and synthesized: a) with different isotropic/anisotropic shapes (spherical, rod-like) and aspect ratios (AR) ranging from 1 to 10; b) with different surface functional groups, able to chemically or physically interact with the rubber. TEM and dynamic-mechanical analyses assessed that surface groups interacting with rubber promote the filler homogeneous distribution. The reinforcing effect is related to the formation of a percolative network of SiO2 nanoparticles connected by thin rubber films. Stronger reinforcement is provided by high AR particles due to their self-alignment and the consequent larger filler/polymer interface compared to spherical ones. The study confirmed that beyond maximizing the particle dispersion, morphology control is mandatory to obtain the desired mechanical properties.

Resume : A well-known problem in pulsed laser deposition (PLD) of thin films from lithium-containing metal oxide targets is that the film often contains reduced Li content compared to the target surface. These experiments are usually carried out in the presence of an oxygen background gas. We analyse the PLD process with an analytic model of a plume gas P expanding into a background gas Q. The time-evolution of P is governed by elastic collisions between the particles of P and Q. The model predicts a reduction in Li content of the thin film compared to the target surface, due to the strong scattering of the light Li atom compared to the weak scattering of the heavy Mn atom by the oxygen gas. The predictions are in quantitative agreement with compositions of real thin films formed by pulsed laser deposition of lithium manganese oxide targets in our laboratory. These results show that there will be inevitable loss of cations when forming thin filmed by PLD on targets containing both light and heavy cations. The target composition must therefore be carefully chosen to obtain high quality thin films with a desired stoichiometry. Reference: D. M. Packwood, S. Shiraki, and T. Hitosugi. Phys. Rev. Lett. 111, 2013, 036101.

Resume : Cellulose from microbial origin, commonly known as bacterial cellulose (BC), is becoming a commodity material since it incorporates desirable structural properties for biomedical applications. Here, we present the production and characterization of bacterial cellulose (BC) films of less than a hundred microns thick produced by Glucoacetobacter bacteria. These thin films are processed using three different drying methods: 1) room temperature, 2) freeze drying and 3) supercritical drying. The different processes confer to the cellulose films a hierarchical porous network, high purity and crystallinity, flexibility and strength (high Young modulus at room and elevated temperatures) and large water holding capacity that can be tailored and controlled for different applications. In this work, we used BC films as platform to incorporate magnetic functionality by the incorporation of iron oxide nanoparticles. Using the microwave-assisted method in a rapid and cost effectively manner, we magnetically coated the whole structure of our BC films. Evaluation of different precursor´s concentrations and taking advantage of the different drying methods we achieved magnetic bacterial films with different magnetic strength. We obtained magnetic BC composites flexible, robust and with high magnetization within few minutes in a clean, easy and reproducible method. In the talk, we would illustrate the synthesis and characterization of the magnetic BC films as well as the flexible and magnetic properties achieved.

Resume : The interest for the synthesis of MOFs ever growths due to their high versatility and potential applications in catalysis, treatment and storage of gas, drug delivery…1-3 MOF are usually obtained by solvothermal synthesis. In our group, we have focused on the synthesis of these compounds by solvo-ionothermal approach, involving tailor-made ionic liquids (ILs) bearing specific coordination functions. Contrary to the literature, where ILs acts only as solvent or template,4, 5 our approach should allow a crystal engineering of these compounds. We will present our recent results concerning the synthesis, structure and characterization of novel transition metal based compounds. Beyond the interest to explore new methods of synthesis and new families of compounds, the incorporation of ILs into the hybrid coordination networks let glimpse the possibility to obtain multiferroic materials.6, 7 1. G. Férey, Chem. Soc. Rev. 37, 2008, 191. 2. P. Horcajada, C. Serre, M. Vallet-Regí, M. Sebban, F. Taulelle, G. Férey, Angew. Chem. Int. Ed. 45, 2006, 5974. 3. M. Dincă, J. R. Long, Angew. Chem. Int. Ed. 47, 2008, 6766. 4. P. J. Calderone, P. M. Forster, L. A. Borkowski, S. J. Teat, M. Feygenson, M. C. Aronson, J. B. Parise, Inorg. Chem . 50, 2011, 2159. 5. W. J. Ji, Q. G. Zhai, S. N. Li, Y. C. Jiang, M. C. Hu, Chem. Commun. 47, 2011, 3834. 6. Z. Lin, A. M. Z. Slawin, R. E. Morris, J. Am. Chem. Soc. 129, 2007, 4880. 7. L. Xu, S. Yan, E. Y. Choi, J. Y. Lee, Y. U. Kwon, Chem. Commun. 2009, 3431.

Resume : Photocatalytic performance of TiO2 nanomaterials has attracted a lot of attentions by designing and modifying various TiO2-based composites. In recent years, graphene-TiO2 hybrid nanomaterials have been widely researched due to the perfect property of the graphene [1], as graphene between the hybrid nanomaterials can lengthen the life-time of photoexcited charge carriers to improve the photoactivity [2]. Therefore, the interface combination between the graphene and TiO2 nanomaterials is quite important for the understanding of the enhancement of their photocatalytic performance. In the present work, we propose a process for synthesizing graphene-TiO2 nanoparticles by a simple solvothermal method, and then the composite materials are used as photocatalysts for degradation of methyl violet, which is expected to obviously enhance the photocatalytic performance comparing with that of the pure TiO2 nanoparticles. SEM and TEM images show that the TiO2 nanoparticles with diameters of 20-30 nm tightly attach on the surface of the graphene sheets. The interface combination of chemical states between the TiO2 nanoparticles and graphene is charactered by Raman mapping spectra, as Raman mapping method is a novel method to provide the distribution information of the composites, and it is found that the uniform dispersion of the graphene in the composites will greatly influence their photocatalytic performance. References: [1]Pan X, Zhao Y, Liu S, et al. ACS Appl. Mater. Interf., 2012, 4: 3944. [2] Zhang Y, Zhang N, Tang Z R, et al. Phys. Chem. Chem. Phys., 2012, 14: 9167.

Resume : Poly(dimethylsiloxane) (PDMS) is the most popular elastomeric material since it couples biocompatibility with excellent elastic properties. For this reason considerable efforts are currently being concentrated on the fabrication of stretchable metallic circuits and microelectrodes integrated on PDMS. Recently it has been demonstrated that neutral metallic nanoparticles produced in the gas phase and aerodynamically accelerated in a supersonic expansion can be implanted in PDMS substrate to form a conductive nanocomposite (nc) with novel functional properties[C. Ghisleri et al., J. Phys. D: Appl. Phys 47,015301 (2014)]. While the effectiveness of this novel technique has been already demonstrated few information are available at the moment on the ncs elastic properties. In particular it is of great importance to characterize the nc elastic properties as a function of the implanted cluster concentration. To this aim we use classical viscoelasticity theory in combination with classical molecular dynamics simulations to estimate the nc Young modulus as a function of the implanted clusters concentration. The results show that the nanocomposite Young modulus is basically unchanged (with respect to pristine PDMS) up to a cluster concentration of 25%; while above 25 % we observe a Young modulus exponential increase.

Resume : We have prepared surface charge controlled graphene oxide (GO) nanomaterials by two methods; modified Hummer?s method and post synthetic treatment with amine moiety on GO. In order to control the degree of oxidation, graphite was reacted with various graphite/hydrogen peroxide ratio of 1, 2 and 4, which resulted in the zeta potential -22, -27, and -32 mV, respectively. Then the GO having -27 mV of zeta potential was reacted with either ammonia or aliphatic diamine. The zeta potential of amine modified GO was determined -19, 2 and 9.1 mV for ammonia, 1,3-diaminopropane and 1,6-diaminohexane modified GO. The X-ray photoelectron and fourrier-transform infrared spectroscopy showed the successful formation of C-O and C-N bonds in the prepared samples. In order to evaluate the cellular interaction of GO nanomaterials depending on their surface charge, we carried out hemolysis assay utilizing human whole blood as well as cellular experiments on human cervical cancer HeLa and lung carcinoma A549 cell culture lines. Hemolysis assay revealed that the GO nanomaterials became hematocompatible with increasing positive surface charge. Cellular toxicity experiments also showed lower cytotoxicity on GO having more positive surface charge. In order to quantify the cellular uptake of GO, we attached fluorescein isothiocyanate on amine-modified GO. It was shown that GO with positive surface charge could be internalized more efficiently into cells compared to the negatively charged ones.

Resume : The tremendous development of LbL coatings is largely due to both their exceptional tolerance to substrate’s nature and topology, and to the very wide library of materials that can be incorporated into the multilayer. However, the sequential deposition process and the weak stability of the obtained films has recently lead some groups to develop other options, yet less functionalizable, such as simultaneous spraying [1], morphogen-driven [2] or continuous assembly [3] approaches. The work presented here opens new perspectives to one-pot self-constructing films by providing the resulting surface platform an access to the wide library of alkyne-azide “click” chemistry compounds and to the unique morphologic properties of electropolymerized a poly(aniline). The Simultaneous Electropolymerization and Electro-Click Functionalization process (SEEC) has been introduced for one pot self-construction of functional polymer films where both polymerization and functionalization are triggered by electrochemistry. As a proof of concept, 4-azido-aniline and ethynylferrocene have been used and studied by CV, XPS, UV, AFM and SEM. A large number of experimental parameters allow to access three main tuning levers and to potentially design platforms for sensors, membranes, fuel cells, supercapacitors, photovoltaics, or smart and stimuli-responsive coatings

Resume : The preparation of novel functional materials inspired from natural materials is attracting considerable interest in the scientific community. The development of environmentally friendly functional composites is promoting the usage of renewable resources. Among various types of renewable resources, proteins and natural polysaccharides shown a wide range of applications in textiles or in the biomedical area. Silk fibroin is a commonly available natural biopolymer produced in specialized glands of arthropods, with a long history of use in textile production and also in health cares. Nowadays, silk fibroin is increasingly explored in other areas and can be find in a higher morphological diversification of silk biomaterials like films, electrospun fibers, 3D porous scaffolds or nanoparticles. New applications such as their use in active components in optical devices, open the way towards the development of multifunctional optoelectronic devices, which in perspective can be made fully biocompatible and eventually bioresorbable. Moreover, fibroin can be added to other biocomponents in order to modify the biomaterial properties leading to optimized and total different functions. The tuning and completely understanding of silk fibers physicochemical properties and interaction with other elements are of crucial importance for the improvement of already existent silk-based materials and the basis for the development of new products.

Resume : Carbon nanotubes’ (CNTs) excellent mechanical properties make CNTs extremely interesting for the use in composites. Hybrid composites can be obtained by growing CNTs onto fibers. The presence of CNTs can strongly influence the fibre/matrix interface. However, how CNTs exactly behave in composites and affect the damage behaviour remain unclear. In this work, CNTs were grown on carbon fibers (CFs) by chemical vapor deposition (CVD). By using the oxidative dehydrogenation reaction of C2H2-CO2, we were able to produce CFs/CNTs hybrid materials without damaging the CFs surface. Uni-directional (UD) nano-engineered CFs reinforced composites (nFRCs) were fabricated using these materials. The fracture surface of the composites was studied parallel to the fibers. The in-situ transverse 3-point bending tests were performed on composites with and without CNTs. In the latter case, small cracks first appeared in the vicinity of defects. Reaching the critical strain, cracks started to develop at the notch tip as a result of fiber-matrix debonding. The crack propagation was discontinuous and originated from a number of debonded interfaces. In the case of nFRCs, the crack propagation sequence was similar. However, the matrix failure around fibers as well as CNTs bridging cracks have been observed. Especially the latter feature has never appeared in the composite without CNTs. These results indicate that the presence of CNTs in nFRCs can affect the damage initiation as well as propagation.

Resume : Functionalized magnetic iron oxide nanoparticles (MNPs) are promising tools for advanced medical applications such as MRI, hyperthermia, drug delivery, etc. In most of their potential applications, the hybrid organic/inorganic nature of the MNPs surface plays a pivotal role in determining their properties. In this contribution, the anchoring process of multifunctional layers is based on MNPs pre-functionalization with the bifunctional linker (3-aminopropyl) phosphonic acid. Various functional molecules have been then bonded to the amino group of the phosphonic monolayer through a multistep approach. In the first step, a beta-cyclodextrin, able to load hydrophobic drugs, was conjugated to the pre-functionalized MNPs. Then polyethylene glycol, folic acid and a rhodamine probe were bonded through activated carboxylic moieties to the remaining amino groups of the monolayer to improve colloidal stability and to impart targeting and fluorescence properties to the nanoconstruct. The validation of each synthetic step was obtained by X-ray photoelectron and FTIR spectroscopies. The ability of the proposed multistep synthetic route for the preparation of efficient multifunctional systems was proved through the evaluation of the functional properties of the organic coated magnetic nanoparticles, such as hyperthermic efficiency, drug loading, colloidal stability, biocompatibility and fluorescence.

Resume : The synthesis of ordered molecular materials on insulating crystals is of great interest for molecular electronics since distinct and novel properties can originate at crystal interfaces. Unfortunately, the number of techniques used for single organic-based interface formation is very limited and show low reproducibility. We present an effective microfluidic strategy for growing molecular-based hetero-interfaces at desired locations. Microfluidic pneumatic clamps embedded in a double layer platform provide a facile and reliable technology for crystal trapping and interface formation. Using this approach we introduce a reducing agent (Ag content) into a trapped in-situ grown TCNQ insulating crystal that reacts leading to AgTCNQ. The Ag diffusion can be stopped guarantying the intimate contact between materials needed to investigate the TCNQ/AgTCNQ interface formation and the electrical properties of the boundary structure as the molecule is reduced. In order to gain information about the structural and electronic properties of the system a combination of Atomic Force Microscopy techniques were employed. Morphological characterization of the interface shows the formation of different regions of reduced material while, by means of conducting atomic force microscopy, a remarkable and distinct electric response between regions is demonstrated. In particular, we obtain a switching behaviour on the crystal surface that is the characteristic of the bulk AgTCNQ material.

Resume : The main challenges faced by the protective weldable coatings have been identified in the industry as follows: 1) Influence of coating thickness on weldability and corrosion resistance properties, specifically: a) Thin films yielding good welding characteristics but inferior protection properties b) Thick films providing improved corrosion resistance at the expense of wedabiltity 2) Lack of mechanical durability that leads to coating damages during handling, storage and transportation 3) Zinc is used to provide galvanic protection, but: a) The weld quality may be affected b) Risks of health hazards when zinc is inhaled from the welding fumes. The key characteristics required to provide robust protective performance together with acceptable weld through capability are identified. Candidate chemistries that offer the opportunity to overcome these previously mutually exclusive behaviours are then explored, together with an approach to designing weldable corrosion-resistant multi-functional hybrid nanomaterials. These are explored though the example of a coating that meets the needs of Industry by building a novel multifunctional hybrid material based on nanomaterials compilation and synergy. The novel coating will be developed in the Weldaprime project (starting 01/02/14; FP7-European funding). This European project aims to develop an innovative coating that will be durable, zinc-free, weldable and provide corrosion protection for steel products for at least 1year.

Resume : Photoactive polymers blended with plasmonic nanoparticles hold promise for the development of cost-effective, lightweight organic photovoltaic (OPV) devices [1]. Although many studies on the photovoltaic performance of plasmonic blends were performed, there are limited reports on their stability. The present work examines aspects of the photodegradation mechanisms during prolonged irradiation of plasmonic OPV blends and their respective devices. For this purpose, the stability characteristics of bulk heterojunction OPV blends incorporating surfactant free Au and Al nanoparticles (NPs) into the photoactive layer is investigated by Laser Induced Fluorescence and transient photoluminescence complemented by device degradation electrical measurements. The effect of NPs incorporation on the aging performance of OPV devices is further explored by correlating the fluorescence evolution over illumination time of pristine and NPs doped active layers with the photovoltaic characteristics of the respective devices. It is shown that besides the improved cell efficiency attributed to plasmon absorption and scattering effects, the embedded NPs act as performance stabilizers, giving rise to enhanced structural stability and, in turn, to reduced photodegradation rate. [1] E. Stratakis and E. Kymakis , Mater Today, 2013, 16, 138-151

Resume : Water soluble gold nanoparticles (GNPs) own physical and chemical properties with a large scope of application in the biomedical research. Our project aims to develop new synthetic pathways for the direct synthesis of GNPs already possessing functionality allowing easy access to bio functionalization. This is achieved by using synthesized water soluble molecules. These molecules are bifunctional : One functional group is able to both reduce gold(III) chloride and to coat the surface of the obtained GNPs. The other functional group will remain inert during the NPs synthesis and will allow further chemoselective GNPs functionalization. Herein we will present the mechanism of this GNPs synthesis. We have demonstrated the related mechanism of this colloid formation and the interaction between our bifunctional molecules and the gold surface by classical analytical chemistry techniques. Optimization of the various synthesis parameters (temperature, concentration and pH) have been assessed to yield homogeneous GNPs of size ranging from 13-21 nm. Then reactions at the surface with the remaining, functional group have been characterized, confirming their chemoselective reactivity. These new GNPs are also used as a building block for sized controlled covalent assemblies preparation. The controlled size assemblies are water soluble and presents specific optical properties shifting from blue to NIR absorption yielding to promising in vivo applications such as hyperthermia.

Resume : In the last decade the investigation of dye-doped hybrid materials has significantly increased because of their promising technological applications [1,2]. The incorporation of dyes into glasses via the sol–gel technique for the production of solid-state dye lasers was first reported in 1984 by Avnir et al. [3]. These authors demonstrated that the encapsulation of fluorescent guest species within hybrid structures is of interest to prevent the aggregation of the dye molecules and thus retain their high fluorescent quantum yield, and to increase their photostability. In the present work we have combined the sol-gel process with self-assembly routes to obtain dye-doped mono-amide cross-linked alkyl/siloxane hybrids (mono-amidosils). The mono-amidosil framework employed (m-A(14)) is a photoluminescent hierarchically structured lamellar bilayer hybrid that consists of 2D siliceous domains, separated by perpendicularly-oriented alkyl chains, self-assembled through tail-to-tail van der Waals interactions and hydrogen bonding interactions [4]. The addition of monomethinecyanine [5] and Rhodamine (B) methyl ester perchlorate dyes [6] to m-A(14) was reported recently. 1. B. Lebeau, P. Innocenzi, Chem. Soc. Rev., 2011, 40, 886. 2. A. Silva, R. E. F. Boto, R. M. El-Shishtaw, P. Almeida, Eur. Polym. J., 2006, 42, 2270. 3. D. Avnir, D. Levy, R. Reisfeld, J. Phys. Chem., 1984, 88, 5956. 4. L. D. Carlos; V. de Zea Bermudez, V. S. Amaral, S. C. Nunes, N. J. O Silva, R. A. Sá Ferreira, C. V. Santilli, D. Ostrovskii, J. Rocha, Adv. Mater., 2007, 19, 341. 5. S. C. Nunes, C. B. Ferreira, J. Hümmer, R. A. S. Ferreira, L. D. Carlos, P. Almeida, V. de Zea Bermudez, J. Mater. Chem. C, 2013, 1, 2290. 6. S. C. Nunes, V. T. Freitas, R. A. S. Ferreira, L. D. Carlos, P. Almeida, V. de Zea Bermudez, J. Sol-Gel Sci. Technol., accepted

Resume : Inspired by Nature, the self-assembly of organic/inorganic hybrid materials provides an adequate approach for the production of hierarchical architectures and multifunctional nanostructures for a wide range of technological applications [1,2]. The combined use of sol-gel chemistry with self-directed assembly processes has been the preferred route to prepare ordered bridged and non-bridged silsesquioxane materials [3-5]. These studies revealed that the degree of order of silsesquioxanes may be easily tuned by subtle modifications of the synthetic conditions and through a judicious choice of the chemical nature of the organic and inorganic components. Recently we investigated a di-amide cross-linked alkyl/siloxane hybrid (di-amidosil, d-A(10)) derived from the (RO)3Si–(CH2)3–NHC(=O)–(CH2)10–C(O=)NH–(CH2)3–Si(OR)3 precursor. Materials with variable degrees of order and morphologies were obtained through a fine control of the experimental conditions (water content, type/concentration of catalyst, and presence/type/concentration of co-solvent) [6]. This work demonstrated that the balance between self-directed assembly and sol-gel condensation reactions that governs structuring of bridged silsesquioxane hybrids depends critically on the chemical nature of the cross-link and on its ability to form a strong, ordered and directional hydrogen bonded array [6]. In the present work we have further investigated the influence of several experimental parameters on the level of organization of the d-A(10) di-amidosil prepared under acid catalysis. 1. C. Sanchez, P. Belleville, M. Popall, L. Nicole, Chem. Soc. Rev. 2011, 40, 696. 2. C. Sanchez, H. Arribart, M. Madeleine, G. Guille, Nature Mater. 2005, 4, 277. 3. J. J. E. Moreau, L. Vellutini, M. Wong Chi Man, C. Bied, J.-L. Bantignies, P. Dieudonné, J.-L. Sauvajol, J. Am. Chem. Soc. 2001, 123, 7957. 4. L. D. Carlos; V. de Zea Bermudez, V. S. Amaral, S. C. Nunes, N. J. O Silva, R. A. Sá Ferreira, C. V. Santilli, D. Ostrovskii, J. Rocha, Adv. Mater., 2007, 19, 341. 5. S. C. Nunes, N. J. O. Silva, J. Hümmer, R. A. S. Ferreira, P. Almeida, L. D. Carlos, V. de Zea Bermudez, RSC Advances, 2012, 2, 2087. 6. S. C. Nunes, J. Hümmer, V. T. Freitas, R. A. S. Ferreira, L. D. Carlos, P. Almeida, V. de Zea Bermudez, submitted

Resume : Polysaccharides are an attractive class of compounds for biomedical applications, due to their biocompatibility and structural similarity with biological systems. Natural polysaccharides often exhibit solubility problems due to the formation of strong and extensive hydrogen bonding interactions. One way of overcoming this problem is to employ ionic liquids (ILs) as solvents [1]. Interestingly, ILs can sometimes act as templates. In the context of the fabrication of scaffolds, this effect is of interest for micropatterning purposes [2]. In the present work we have synthesized and characterized silica-based hybrids composed of pectin or xanthan gum (XG). Different ILs, acting simultaneously as solvents and porogenic agents, have been incorporated with the goal of producing scaffolds for bone regeneration. Pectins are a family of covalently linked D-galacturonic acid-rich polysaccharides present in the primary cell walls of plants [3]. XG is a high molecular weight polysaccharide produced by Xanthomonas Campestris in aerobic conditions from sugar cane, corn or their derivatives [4]. XG is widely used in food, pharmaceuticals and personal care. [1] R. P. Swatloski, S. K. Spear, J. D. Holbrey and R. D. Rogers, J. Am. Chem. Soc., 2002, 124, 4974. [2] U. Sang Shin, J.-G. Kim, Bull. Korean Chem. Soc. 2012, 33, 2295. [3] D. Mohnen, Curr. Opin. Plant Biol. 2008, 11, 266. [4] V. Blasques Bueno, R. Bentini, L. H. Catalani, D. F. S. Petri, Carbohydrate Polym., 2013, 92, 10.

Resume : High surface area palladium incorporated mesoporous, nano-structured MCM-41 catalysts have been synthesized using the wet impregnation technique and the catalytic activiy was tested in a gas phase reaction system. The one-pot oxidative synthesis of ethyl acetate was performed in a fixed bed reactor, into which 0.2 gram catalyst was loaded, was heated to the reaction temperatures using a tubular furnace Parameters to be tested involved the reaction temperature which ranged between 100-250oC and O2/EtOH molar ratio which ranged between 0.5 (stoichiometric ratio) and 1.0. It was seen that the two main reaction products were ethyl acetate and acetaldehyde. Carbon dioxide was formed due to complete oxidation however no carbon monoxide was released as a result of partial burning. Some acetic acid formation was also detected. The selectivity and yield of ethyl acetate along with reaction conversion increased until 225oC and started decreasing at 250oC implying the poisining of the catalyst at this temperature. The optimum reaction yield was obtained as 0.308 for an O2/EtOH molar ratio of 0.9 at 225oC.

Resume : In the past years, thanks to the availability of new advanced high performance materials, printable and environmental friendly electronic has led to the rapid development of miniaturized electronic devices. These devices could be integrated on substrates in order to facilitate both the manufacturing process and the portability. From the environmental point of view, polymeric matrices that can be obtained from plant renewable sources not in competition with the food chain are certainly the best solution. These materials, in addition to being derived from renewable source, may also be biodegradable under specific conditions. These characteristics, together with their easily processability with various industrial manufacturing techniques and the possibility to generate hybrids with the combination of different nanoparticles, make them excellent candidates for the development of new electronic devices, which associate the miniaturization of the electronic component with the low environmental impact of the matrix in which they are hold. In this context, the work here presented aims to explore the potential use of graphene hybrids. They represent a class of recently developed composite materials with unique functional properties for the development of sensors and optoelectronic devices integrated in eco-friendly supports. In this work the functionalization strategy, the ink formulation and printing as well as the technologies for graphene hybrids transfer will be reviewed and disc

Resume : Hybrid inorganic/organic materials have found many applications because they allow combining the properties of inorganic solids such as robustness, durability or mechanical strength with those introduced by the organic component such as functionality, tunability and convenient derivatization by synthesis. Recently, graphene (G) and related 2D materials have attracted a considerable attention due to their high conductivity, high Young’s modulus and the possibility to be tailored by chemical modification. In this sense, layered double hydroxides (LDHs) are promising candidates for the development of hybrid functional materials due to their chemical versatility and the broad range of applications they exhibit. Among these applications, those related with energy storage are of utmost importance. In this context, we are interested in the development of hybrid G/LDHs materials active as oxygen evolution reaction (OER) electroctalyst. Herein, we have developed the one-pot formation of a nanocatalyst by in-situ hybridization of NiFe-LDH with G exhibiting high OER catalytic activity. Moreover, the low-temperature annealing under N2 of the hybrid gives rise to an active 2D strongly coupled bi-component NiO/NiFe2O4-G. Furthermore, we have deeply characterized their physical and electrochemical properties shedding light on their behaviour as electrode material for supercapacitors, and as efficient OER electrocatalyst, obtaining excellent performances.

Resume : We will present a simple fabrication of hybrid nanowires (NWs) composed of a p-type conjugated polymers (CPs) and n-type inorganic quantum dots (QDs) by exploiting the crystallization-driven solution assembly of poly(3-hexylthiophene)-based rod-coil amphiphiles. The visualization of the crystallization-driven growth evolution of hybrid NWs through systematic transmission electron microscopy (TEM) experiments showed that discrete dimeric CdSe QDs bridged by CPs were generated during the initial state of crystallization. These, in turn, assemble into elongated fibrils, forming the coaxial hybrid NWs. In particular, the location of the QD arrays within the single strand of CP NWs can be controlled precisely by manipulating the regioregularity (RR) values of P3HT block and the relative ratios of blocks. The degree of coaxiality of the QD arrays was shown to depend on the coplanarity of the thiophene rings of P3HT block, which can be controlled by the RR value of P3HT block. In addition, we demonstrate that the location of QDs could be regulated at the specific-local site of NW according to the surface characteristics of QDs. As an example, the comparison of two different QDs coated with hydrophobic alkyl-terminated and hydroxyl-terminated molecules, respectively, is used to elucidate the effect of the surface properties of QDs on their nano-location in the NW.