WiRE: Women in Renewable Energy

Resume : Perovskite nanocrystals (NCs) have gained significant attention for both fundamental research and applications of optoelectronic devices owing to their appealing optoelectronic properties and excellent chemical processability. For their wide range of potential applications, synthesizing colloidal NCs with high crystal quality and stability is of crucial importance. However, like most common NC systems, those reported perovskite NCs still suffer from a certain density of trapping defects, giving rise to detrimental non-radiative recombination centers and thus quenching luminescence. Very recently, we have suceeded in synthesis of phase stable and less defect preovksite NCs, including APbX3 NCs (A: FA, MA, Cs; X: I, Br, Cl), Sn-Pb alloyed NCs and Pb-free Sn based NCs [1-6]. We have demonstrated that a high room-temperature photoluminescence quantum yield (PL QY) of close to 100% can be obtained in the APbX3 perovskite NCs, signifying the achievement of ignorable less trapping defects in the APbX3 NCs. Ultrafast kinetic analysis with time-resolved transient absorption spectroscopy and photoluminence evidences the negligible electron or hole trapping pathways in our NCs, which explains such a high quantum efficiency. In addtion, photoexcited hot and cold carrier dynamics as well as charge transfer at the heterojunction of NC/metal oxide were systematically investigated [4]. Solar cells based on these high-quality perovskite NCs exhibit power conversion efficiency of close to 15%, showing great promise for practical application. On the other hand, through incorporation of alkali ion Na+, we have realized for the first time efficient near-infrared emission from highly defective Sn-Pb perovskite QDs with substantially improved PL QY from ~0.3% to 28% [5]. Our findings provide new insights into the materials design strategies for improved optoelectronic properties of Sn-containing perovskites. We anticipate their use in near-infrared devices is very promising if issues of the sustainability of PL QY can be fully addressed in the near future. References [1]. Shen, Q., et al., ACS Nano 2017, 11, 10373. [2]. Shen, Q., et al., J. Am. Chem. Soc. 2017, 139, 16708. [3]. Shen, Q., et al., Chem. Mater. 2020, 32, 1089. [4]. Shen, Q., et al., Nano Energy 2020, 67, 104267. [5]. Shen, Q., et al., Angew. Chem. Int. Ed. 2020, 59, 8421. [6]. Shen, Q., et al., ACS Appl. Nano Mater. 2021, 4, 3958.

Resume : Perovskite photovoltaic is emerging as one of the most competitive solar technology due to its excellent optoelectronic property, such as high absorption coefficient, long carrier diffusion length. The development of perovskite solar cell technologies toward higher power conversion efficiency (PCE) requires delicate control over the perovskite film and the relevant interfaces, and deep understanding of defects. The properties of the perovskite film can be optimized by careful control of the intercalation reaction between the organic and inorganic species during film formation. Two related aspects are discussed: 1) Develop liquid medium annealing process1 that leads to the films with high crystallinity, less defects, desired stoichiometry, and overall film homogeneity, to achieve high performance photovoltaics with certified efficiency of 24.9%; 2) Propose methods such as "redox ion pair" and "multiple non-covalent bond synergistic effect" to suppress defect pairs in a sustainable way2,3, which greatly improved the long-term stability of perovskite solar cells for over 2000 h under the stressors, e.g. light, heat, and electricity. Corresponding degradation mechanism of hybrid perovskite films and devices under operational conditions are revealed on the molecular and atomic scales. The fabrication of high performance perovskite solar cells (25%) was conducted from solution at low temperatures, which should simplify future manufacturing of high performance, low-cost, and large-area perovskite solar cells. References [1] N.X. Li, et al., Science, 2021, 373, 561. [2]. L.G. Wang, et al., Science, 2019, 363, 265. [3] N.X. Li, et al.,Nature Energy, 2019, 4, 408–415.

Resume : Layered hybrid perovskites are promising materials for optoelectronic applications due to their modular structure, in particular in the corresponding Dion–Jacobson (DJ) and Ruddlesden–Popper (RP) phases. They have attracted considerable attention due to an increased stability as compared to 3D perovskite analogues, whereas their soft nature permits controlling the optoelectronic properties by using external stimuli, such as pressure, without changing their composition. However, the response of these materials to pressure that is compatible with practical applications (<1 GPa) remains unexploited. We apply hydrostatic pressure to representative iodide and bromide DJ and RP 2D perovskites based on 1,4-phenylenedimethylammonium (PDMA) and benzylammonium (BzA) spacers in the 0–0.35 GPa pressure range. X-ray scattering experiments in conjunction with DFT calculations under pressure reveal that these effects are related to the structural properties of the corresponding 2D phases. Despite different binding modes of the spacers, we find that RP and DJ perovskites behave similarly in this pressure range, with an anisotropic response predominantly in the out-of-plane (a-axis) direction. Moreover, while PDMA-based DJ systems were not found to be susceptible to the changes associated with the halide anion, BzA-based RP perovskites result in a larger effect for Br-based compositions that is in contrast with their higher expected level of rigidity. Specifically, a significant relaxation of Pb–X–Pb angle in the non-centrosymmetric (BzA)2PbBr4 phase is accompanied by an isostructural phase transition, resulting in a large compression under mild pressures. This study thereby provides important insights into the mechanochromic properties of layered hybrid perovskites, whereas the unique reversibility of their response expands the perspectives for future applications. Reference: A. Muscarella, A. Dučinskas, M. Dankl, M. Andrzejewski, N. P. M. Casati, U. Rothlisberger, J. Maier, M. Graetzel, B. Ehrler*, J. V. Milić*, Adv. Mat. 2022, under revision

Resume : Metal-halide perovskites made a breakthrough in the photovoltaic and light-emitting technologies photovoltaics field in the last ten years. MHP are one of the most promising low-cost materials to revolutionize both technologies, due to their excellent optoelectronic properties and fabrication versatility. Since the advent of the first perovskite solar cells (PSCs) in 2009, their power conversion efficiency (PCE) has now reached 25.6% [1], for active areas smaller than 1 cm2. Moreover, their operational stability is also constantly improving [2-4]. The interest in transferring the existing technology into large-area perovskite modules using industrial compatible techniques is exploding. Lately, we have demonstrated highly efficient, large area, planar PSCs where the MAPbI3 perovskite layer has been deposited by thermal co-evaporation. The co-evaporated perovskite thin films are uniform over large areas with low surface roughness, and a long carrier lifetime. The high-quality perovskite thin films together with vacuum processed charge transport layers PSCs with PCE above 20% in both n.i.p [5, 6] and p.i.n [7] configurations. The co-evaporated MAPbI3 PSCs guarantee also an impressive thermal and environmental stability maintaining over ≈80% of their initial PCE after 3600 under continuous thermal aging at 85 °C without encapsulation. Indeed, these PSCs demonstrate remarkable structural robustness, absence of pinholes, and intact interfaces with the HTM, upon prolonged thermal aging. [8] The co-evaporated mini-modules achieved record PCEs up to 18.7% for active areas larger than 10 cm2 [5] [9]. Moreover, looking forward to tandem integration and building-integrated photovoltaics we have also developed coloured semi-transparent PSCs and mini-modules for all the range of colours realized. These results represent a significant step towards the commercialization of the technology References 1. NREL. Best Research-Cell Efficiency Chart; U.S. Department of Energy; https://www.nrel.gov/pv/cell-efficiency.htm. 2. S. Yang, S. Chen, E. Mosconi, Y. Fang, X. Xiao, C. Wang, Y. Zhou, Z. Yu, J. Zhao, Y. Gao, Science 2019, 365, 473. 3. Y. Wang, T. Wu, J. Barbaud, W. Kong, D. Cui, H. Chen, X. Yang, L. Han, Science 2019 365, 687. 4. MV Khenkin, EA Katz, et al., M Lira-Cantu, Nature Energy 5, 35-49 5. J. Li, H. Wang, X. Y. Chin, H. A. Dewi, K. Vergeer, T. W. Goh, J. W. M. Lim, J. H. Lew, K. P. Loh, C. Soci, T. C. Sum, H. J. Bolink, N. Mathews, S. Mhaisalkar, A. Bruno, Joule 2020, 4, 1035 6. J Li, HA Dewi, W Hao, N Mathews, S Mhaisalkar, A Bruno, Coatings, 2020 10(12), 1163 7. J Li, HA Dewi, W Hao, J Zhao, N Tiwari, N Yantara, T Malinauskas, V Getautis, T J. Savenije, N Mathews, S. Mhaisalkar, A Bruno, Adv. Funct. Mater. 2021. 8. L Li, HA Dewi, W Hao, L Jia Haur, N Mathews, S Mhaisalkar, A Bruno, Solar RRL, 2020, 4, 2000473 9. HA Dewi, L Li, W Hao, N Mathews, S Mhaisalkar, A Bruno, Adv. Funct. Mater. 2021 2100557

Resume : The conceptual idea of the integration of energy photovoltaic (PV) generation and storage systems in a single unit simultaneously is a powerful means to use energy more efficiently, improving the system performance, reducing device size and weight, and widening the possible applications applicability. Lightweight, bendable PV devices and storage systems can be used in various applications, like transportable electronic chargers, flexible displays, biomedical devices, conformable sensors, and wearable electronic textiles, therefore attracting significant attention both from the scientific and industrial community. In this context, an emerging technology for photovoltaic generation is represented by flexible perovskite solar cells (FPSCs) that have reached over 20% power conversion efficiency (PCE) on small area, adopting the planar structure as the preferred architecture because of its simplicity and low temperature fabrication, and PCE 15,5% for modules on 16 cm2 active area [1,2]. For what concerns the flexible storage, supercapacitors are gaining considerable attention as they can also be realized with simple printing low cost processes and in this case the active materials used can be also environmentally friendly. They normally can deliver high power densities in the range of hundreds of W/Kg and energy densities in the range of dozens of Wh/Kg [3]. In literature, the integration of the two devices has been demonstrated only on rigid substrates, with a maximum operating voltage of 0,84 V when the supecap is charged by a single solar cell [4]. In this presentation, the fabrication of flexible perovskite devices will be reported focussing in particular on the role of the scaling up of the fabrication process from solar cells to module which allowed the FPSMs to deliver 12% PCE and negligible hysteresis on 16.8 cm2 and 11.7% PCE on 21.8 cm2 active area [5-8]. Printed supercapacitors realized with environmentally friendly with will be presented both with a vertical and planar architecture which achieved a maximum specific power densities above 20 µW cm-2 [9]. A possible strategy for the integration of the two devices will be also shown showing the criticity in the final assembly of the two systems. References [1] Wu, C. et al. Advanced Functional Materials (2019), 29 (34), 1902974. [2] J. Chung et al. Energy Environ. Sci., (2020),13, 4854-4861 [3] C. V.V.Muralee Gopi et al. Journal of Energy Storage, (2020),Vol. 27, 101035 [4] Z.Liu et al. ACS Appl. Mater. Interfaces (2017), 9, 27, 22361–22368 [5] B.Taheri et al. Energy Technology (2020), doi.org/10.1002/ente.201901284 [6] B.Taheri et al. (2021) ACS Applied Energy Materials, doi.org/10.1021/acsaem.1c00140 [7] F. De Rossi et al. Journal of Power Sources, (2021) Volume 494, 229735. [8] F.De Rossi et al. (2021) Nano Energy, 106879. [9] G. Polino et al. (2020) Energy Technology, doi.org/10.1002/ente.201901233

Resume : When it comes to meeting our energy requirements, solar energy is regarded as a promising alternative to fossil fuels. In particular, perovskite solar cells (PSCs) are the most emerging area of research among new generation photovoltaic technologies, owning to their high power conversion efficiency (PCE) and low processing cost. Since the first-time reported all-solid state PSCs in 2012,[1] important enhancements have been done in the deposition methods, control of the interface, chemical composition, and synthesis technique, among others. However, the stability of PSCs has been a long-standing question.[2] To address this point, we firstly investigated a series of fluorous cations, varying in size and shape, as building blocks for a new family of fluorous 2D lead-iodide perovskites. Importantly, it was demostrated that the fluorous moiety confered extreme stability to the low dimensional perovskites and enhanced the hydrophobic character of the perovskite surface, which remained perfectly stable for more than one month in ambient conditions.[3] Nowadays, engineering two-/three-dimensional (2D/3D) PSCs is a popular strategy for efficient and stable devices. Nevertheless, the precise function of the 2D/3D interface in controlling the durability of the solar device is still vague. Interestingly, we revealed a dynamical structural mutation of the 2D/3D interface employing a series of bulky thiophene-terminated cations (2-TMAI, 3-TMAI, and 2-TEAI) as building blocks for layered 2D perovskites. As a result, it was demonstrated that the judicious choice of the organic barriers can lead to structurally stable and robust 2D overlayers with a decisive role in improving device stability under illumination.[4] As a different approach to enhance the lifetime of PSCs, we specifically designed and synthesized two novel organic molecules based on electron-rich spiranic cores (spiro-POZ and spiro-PTZ) to be implemented as hole-transporting materials (HTMs) in PSCs. In particular, two different [(FAPbI3)0.87(MAPbBr3)0.13]0.92[CsPbI3]0.08-based device architecture were studied: mesoporous and planar, reaching PCEs up to 18.36% for spiro-PTZ, comparable with the PCE obtained with spiro-OMeTAD. Notably, the doped-HTMs exhibited excellent long-term stability in planar devices, retaining over 84% of PCE after more than 300 days in ambient conditions. Moreover, the PCE decreases by only 6% after 1200 h, under continuous 1 sun illumination.[5] These impressive results confirm that long-term stability in PCEs can be nicely achieved controlling the interface at the perovskite layer and using doped HTMs by design. References [1] Hui-Seon Kim, et al., Sci. Rep., 2012, 2, 591. [2] M. K. Rao, et al., Sol. Energy, 2021, 218, 469-491. [3] I. García-Benito, et al., Chem. Mater, 2018, 30, 8211−8220 [4] A. A. Sutanto, et al., J. Mater. Chem. A, 2020, 8, 2343–2348. [5] J. Urieta-Mora, et al., Sol. RRL, 2021, 2100650.

Resume : Two-dimensional (2D) transition metal dichalcogenides (TMDs) posses unique and tunable optoelectronic properties making them promising candidates for use in a range of applications such as transistors, membranes, solar cells, and photoelectrodes. Due to their chemical robustness, they show particular promise in the field of solar-to-chemical energy conversion as thin film photoelectrodes for solar H2, O2, or I2 production. While promising demonstrations have been made, the main obstacle in the way of realizing commercially-viable 2D TMD based devices is the large-scale production of high-quality thin films.[1] To address this our group has developed powder-based solution processable methods for producing high quality 2D TMD nanosheet dispersions which are then facility processed into ultrathin, yet robust films for optoelectronic applications. We highlight our recent work exfoliating MoS2 via a large molecule electrointercalation route and compare it to traditional solution processable methods such as ultrasonication. We show that our new method yields thinner nanosheets with large surface areas while producing lower defect densities. When processed using our in-house developed liquid-liquid interfacial self-assembly (LLISA) technique,[2] we achieve single layer nanosheet films with high internal quantum efficiencies (IQE) leading to high photocurrent densities (Jph). We then expand this technique to other TMDs including WSe2 to demonstrate improved solar water reduction compared to ultrasonication. We briefly discuss further upscaling of our film deposition technique towards m2 area films and address additional strategies for improving solar fuel production including type II heterojunctions and post-film treatment techniques for defect mitigation.[3,4] References: [1] Yu, X.; Sivula, K.. ACS Energy Lett. 2016, 1 (1), 315–322. [2] Yu, X.; Prévot, M. S.; Guijarro, N.; Sivula, K. Nat. Commun. 2015, 6, 7596. [3] Wells, R. A.; Johnson, H.; Lhermitte, C. R.; Kinge, S.; Sivula, K.. ACS Appl. Nano Mater. 2019, 2 (12), [4] Yu, X.; Guijarro, N.; Johnson, M.; Sivula, K. Nano Lett. 2018, 18 (1), 215–222.

Resume : Copper has been claimed to be a unique material in the conversion of CO2 electrochemically as it allows the formation of C-C species. As a consequence CO2 reduction has been mostly modeled for copper surfaces under ordered conditions, i.e. several crystal planes. However, electrochemical conditions are far from these idealized systems and compositional, dynamic and electrolyte effects are crucial to understand the real properties of differently prepared materials. Establishing robust structure-activities relationships to go beyond Cu and find suitable catalyst for these and more complex transformations. [1-3] References [1]. Dattila, F., et al., ACS Energy Letters 2020, 5 (10), 3176. [2]. Monteiro, M.C.O., et al., Nature Catalysis 2021, 4 (8), 654. [3]. Pablo-Garcia, S., et al., Catalysis Science & Technology 2022, 12, 409.

Resume : Current societal challenges in terms of energy storage have prompted to an intensification in the research aiming at unravelling new high energy density battery technologies with the potential of having disruptive effects in the world transition towards a less carbon dependent energy economy through transport electrification and renewable energy integration. Aside from controversial debates on lithium supply, the development of new sustainable battery chemistries based on abundant elements is appealing, especially for large scale stationary applications. Interesting alternatives are to use sodium, magnesium or calcium instead of lithium. While for the Na-ion case fast progresses are expected as a result of chemical similarities with lithium and the cumulated Li-ion battery know how over the years, for Ca and Mg the situation is radically different. On one hand, the possibility to use Ca or Mg metal anodes would bring a breakthrough in terms of energy density, on the other, development of suitable electrolytes and cathodes with efficient multivalent ion diffusion are bottlenecks to overcome.[1] Calcium concepts have been less explored despite exhibiting interesting prospects. The achievement of reversible plating/stripping o in organic electrolytes prompted the screening of suitable positive electrodes.[2] Both traditional intercalation hosts, such as TiS2, and alternative inorganic materials have been investigated with diverse success.[3] Electrochemical extraction of calcium in some ternary transition metal ions is feasible but the reversibility of the process is more difficult to achieve, which is likely related to strong solvation of calcium ions, with reactions sometimes involving solvent co-intercalation and high cell overpotential. Overall, there is a long and winding road to follow before reliable proof-of-concept can be achieved and technological prospects evaluated. Development of reliable experimental setups, including reference and counter electrodes, coupled to complementary characterization techniques, as well as computational tools, is mandatory if steady progress is to be achieved. [1]. Ponrouch, A., Bitenc, J., Dominko, R., Lindahl, N., Johansson, P., Palacin, M. R., Energy Storage Materials 2019, 20, 253. [2]. Ponrouch, A., Frontera, C., Barde, F., Palacin, M. R., Nature Materials 2016, 15, 169 [3]. Arroyo-de Dompablo, M.E., Ponrouch, A., Johansson, P., Paladin, M. R., Chemical Reviews 2020, 120(14), 6331.

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Resume : Commercialization of differential scanning calorimetry (DSC) fifty years ago led to widespread use of calorimetric methods for thermal characterization. Modern DSC instruments can measure physical transitions, the kinetics of reactions, and other transformations quickly and easily. A material’s glass transition temperature provides insights to its mechanical, chemical and thermodynamic properties. Measuring the glass transition temperature of many functional polymer systems is, however, often difficult due to varying molecular weights, dispersity, and low degree of crystallinity. Hence, traditional DSC methods are usually not sensitive enough to detect the heat response that reflect the material’s glass transition. Fast scanning calorimetry (FSC) can measure at rates greater than 10,000 K/s, allowing for the measurement of isothermal crystallization and study of the formation of glasses. Some semi-crystalline polymers have reported glass transition temperatures that span 50 degrees Celsius or more. Knowledge of the ‘true’ glass transition, other important phase transitions and, e.g., their solidification kinetics can be obtained by measuring relaxation enthalpies with FSC. This method of quenching from the melt and isothermally aging the material provides a glass transition temperature that is not rate dependent and can provide information on the existence of mobile and rigid amorphous phases, all of which are important in material processing as well as in establishing relevant structure/property interrelations. We discuss how the FSC technique can be used for the identification of thermodynamic transitions of donor polymers (PCDTBT) and acceptor molecules (fullerene derivatives) commonly used in the organic solar cell area. Moreover, we provide examples how the change in glass transition temperature of PCDTBT can be tracked before and after UV-light curing. Other illustrations involve inorganic/organic hybrid materials of different crosslink densities and how this affects the glass transition of the final structures. Accordingly, thermal analysis can be exploited to obtain important structural information of this new class of materials and, in turn, processing guidelines can be established towards materials of specific optical or electrical characteristics, and improved materials design for organic photovoltaic blends.

Resume : Next generation of energy storage devices may largely benefit from fast and solid Li+ ceramic electrolyte conductors to allow for safe and efficient batteries and fast data calculation. For those applications, the ability of Li-oxides to be processed as thin film structures and with high control over Lithiation and phases at low temperature is of essence to control conductivity. Through this presentation we review the field from a new angle, not only focused on the classics such as Li-ionic transport and electrochemical stability window for Li-solid state battery electrolytes, but focusing on opportunities and challenges routes in thermal and ceramic processing of the components and their assemblies with electrodes. Oxide vs. Sulfide based solid state battery materials and designs will be reflected on.Also, we will carefully review and give perspectives on the role of solid state battery ceramic strategies for the electrolyte on the electrode interfaces and towards charge transfer and vs. current densities. In other words, it will be a little ceramicist (own) love story on the good and the evil we can design by smart ceramic manufacture at the interfaces originating by the very first choices made in the electrolyte ceramic structure and material design. In the second part of the talk we will discuss new opportunities on low temperature processing of solid state electrolyte ceramics that do not technically require “classic sintering” and avoid prior particle calcination; instead demonstrating opportunities to use unique liquid based direct densification routes and vacuum techniques to design solid electrolytes and grafting interfaces to new hybrid and solid state battery prototypes targeted at processing below 700C for all parts. Collectively, the insights on solid state energy storage provide evidence for the functionalities that those Li-solid state material designs can have for cost and mass manufacturable solid state and hybrid battery prototypes. References for further reads Photo-enhanced ionic conductivity across grain boundaries in polycrystalline ceramics T. Defferriere, D. Klotz, J.C. Gonzalez-Rosillo, J.L.M. Rupp, H.L. Tuller Nature Materials, 1-7 (2022) Processing thin but robust electrolytes for solid-state batteries M. Balaish*, J.C. Gonzalez-Rosillo*, K.J. Kim, Y. Zhu, Z.D. Hood, J.L.M. Rupp Nature Energy, 6, 227–239 (2021) Photo-enhanced ionic conductivity across grain boundaries in polycrystalline ceramics T. Defferriere, D. Klotz, J.C. Gonzalez-Rosillo, J.L.M. Rupp, H.L. Tuller Nature Materials, in press (2022) Solid‐State Li–Metal Batteries: Challenges and Horizons of Oxide and Sulfide Solid Electrolytes and Their Interfaces K.J. Kim*, M. Balaish*, M. Wadaguchi, L. Kong, J.L.M Rupp Advanced Energy Materials, 202002689 (2021) Lithium-film ceramics for solid-state lithionic devices Y. Zhu, J.C. Gonzalez-Rosillo, M. Balaish, Z.D. Hood, K.J. Kim, J.L.M. Rupp Nature Review Materials, 6, 313–331 (2020) High energy and long cycles K.J. Kim, J.J. Hinricher, J.L.M. Rupp Nature Energy, 5, 278–279 (2020) All ceramic cathode composite design and manufacturing towards low interfacial resistance for garnet-based solid-state lithium batteries K.J. Kim and J.L.M. Rupp Energy & Environmental Science, 13, 4930-4945 (2020) A low ride on processing temperature for fast lithium conduction in garnet solid-state battery films R. Pfenninger, M. Struzik, I. Garbayo, E. Stilp, J.L.M. Rupp Nature Energy, 4, 475–4832019 (2019) Spray Pyrolysis Processing of The Electron - Ion Insulator for Metal Anode Adhesion in Solid State Batteries S. Chakravarthy, W.S. Chang, H. Chu, J. Hinricher, Z.D. Hood, Y. Huang, S.Y. Kim, J. Li, A. Maurano, K. Pei, J.L.M. Rupp, Z. Wang, Y. Zhu MIT-Samsung IP case : 23978J (2022) Dual-Phase Composite Li-Conducting Thin Film and Method of Making the Same Y. Zhu, Z. Hood, J. Hinricher, W.S. Chang, H.C. Lee, L. Miara, J.L.M. Rupp IP: US 63/180,150 (2021) Electron-ion insulator for metal anode adhesion in solid state batteries. Z. Wang, J. Rupp, Y. Chen, A. Maurano, S. Chakvararthy, K. Pei, J. Li IP: US 17/144,687 (2021) Amorphous Nitrogen-Rich Solid State Electrolyte J.L.M. Rupp, W.S. Chang, Z. Hood, L. Miara IP: US 63/051024 (2020) Bilayer component for Li metal battery and their use therein. Z.D. Hood, W.S. Chang, L. Miara, J.L.M. Rupp. IP: US 62/994,466 (2020) Lithium Solid Electrolyte and Method of Manufacture Thereof Y. Zhu, W.S. Chang, L. Miara, J.L.M. Rupp IP: US 62/863,059 (2019)

Resume : Low cost solution processed techniques such as chemical bath deposition, hydrothermal and solvothermal methods, sol-gel and SILAR synthesis, have been implemented to obtain Sb2(SxSe1-x)3 solar cells1-3 and Sb-based composites as anode materials in sodium and lithium ion batteries4-6. The design of novel architectures based on Sb-chalcogenides or oxides to overcome volumetric variations that lead to electrode pulverization in alkali ion batteries, or to carrier recombination in solar cells, relies on the characterization of the various interfaces probe by microscopic and spectroscopic techniques. Surface photovoltage spectroscopy, Raman spectroscopy and Electrochemical impedance spectroscopy, along with theoretical calculations, have made possible to introduce interfacial modifiers to improve the different aspects of materials and device design, reflected in the superior conversion efficiency (solar cells) and electrochemical performance (batteries) of the Sb-based devices. 3D carbon network composed of carbon nanotubes and graphene nanoribbons (CNT/GNR), as well as sulfur and Sb doping of these carbon matrices, have been key to control interface passivation, improve charge transfer, allow superior ion diffusion and contribute to the structure stability of the device. In this contribution some examples will be given of the methodology used to better understand the basic phenomena behind the champion devices. References [1] Agustin Baron-Jaimes, A., et al., Sol. RRL 2021, 2000764. [2] Jaramillo-Quintero, O.A., et al.,.Applied Surface Science 2020, 526, 146705. [3] Miranda-Gamboa, R.A., et al., J. Colloid & Interface Science 2019, 535, 400. [4] A. G. El Hachimi, A.G., et al., Int J Quantum Chem. 2021, e26779. [5] Jaramillo-Quintero, O.A., et al., RSC Adv. 2021, 11, 31566-31571 [6] Jaramillo-Quintero, O.A., J. Colloid and Interface Science 2021, 585, 649

Resume : In this communications we will share the advantages of the soft-template application of small-molecule single-crystalline nanowires with the one-reactor plasma-assisted deposition and processing approach.[1] This approach has fostered the development of multifunctional supported nanoarchitectures with applications ranging from photonics to superwettable surfaces, including nanosensors and nanostructured solar cells.[2] Herein, we will focus on the fundamentals of this innovative approach and the particular impacts on the development of piezoelectric and hybrid piezo-triboelectric nanogenerators. Thus, we will address the fabrication of core-multishell piezoelectric nanogenerators including conducting and polycrystalline piezoelectric shells in supported nanowires[3] and paper-based selfpowered sensors and demonstrate the advantages of the application of plasma-assisted deposition and plasma nanoengineering to optimize the performance of hybrid piezo-triboelectric harvesters.[4] References [1]. Borrás, A., et al., Nanoscale 2021, 13 (32), 13882. [2]. Borrás, A., et al., Adv. Mater. Inter. 2021, 8 (21), 2170122; Borrás, A., et al., ACS Appl. Mater. Interf. 2018, 10 (14), 11587; Borrás, A., et al., Nanoscale 2017, 9, 8133. [3]. Borrás, A., et al., Nano Energy 2019, 58, 476-483. [4]. Borrás, A., et al., Nano Energy 2022, 91, 106673.

Resume : Layered Zintl phases have been shown to have favorable thermoelectric properties primarily due to high mobility of charge carriers and very low lattice thermal conductivity. These compounds include CaZn2Sb2, Mg3Sb2, and Eu2ZnSb2, which have been extensively studied. Yb2CdSb2 is another layered compound that has been shown to have promising thermoelectric properties. This compound crystallizes in the noncentrosymmetric orthorhombic space group C¬mc21 and consists of layers of CdSb4/2 corner shared tetrahedra with Yb cations located within and between the layers. The structure of the solid solution, Yb2-xEuxCdSb2, shows site selectivity with Eu preferencially occupying the interlayer site and has been shown to have optimal properties at x ~ 0.3 with a zT ~ 0.7 at 523 K. Interest in optimizing this compound further has led to several additional investigations, including Yb2-xCaxCdSb2 and Yb2-xSrxCdSb2. In this work, the synthesis, structure and properties of the compositions of Yb2-xEuxCdSb2 from x = 0 – 0.5 will be presented and discussed in light of recent Pair Distribution Function (PDF) analysis showing the impact of defects on the properties of the various solid solutions reported to date. Several synthetic routes to the Yb2-xEuxCdSb2 compositions and the impact on properties will be presented and dicussed.

Resume : The rapid adoption of Electric vehicles (EV) comes as a response to mitigate the global greenhouse gas emissions in the transport sector. The demand for Battery inevitably increases with the increasing shift to EVs. As per the IEA global EV outlook 2021, Lithium-ion batteries which currently power the EVs reached global manufacturing capacity of roughly 300 GWh per year and the production was around 160 GWh in 2020. Battery demand is set to increase significantly over the coming decade, reaching 1.6 TWh in the Stated Policies Scenario and 3.2 TWh in the Sustainable Development Scenario The rapid increase poses serious waste-management challenge for battery at its end-of-life (EoL). However, waste also represents a valuable resource as recovering the materials contained in electric-vehicle batteries will re-introduce the recovered material back into the supply chain and also prevent the stockpiling in landfills. Recycling has undoubtedly many benefits, the recovery of materials help meet the demand and reduces mining of primary raw material. This maximises the economic value and contributes to the fundamental aspect of circular economy. Also, by avoiding deposition of used batteries in landfills, it prevents the toxic waste from entering the environment. This paper presents an overview of the battery recycling ecosystem starting with battery recycling methods such as pyrometallurgy, hydrometallurgy, and direct recycling for different battery chemistries and challenges faced in scaling the recycling industry. The paper will also review the policies currently in place for battery recycling in the countries: India, Germany, United States, China, and Japan. Policies significantly drive the recycling practices across the globe. China for instance, has New Energy Vehicle (NEV) recycling regulation which sets recovery rates for battery minerals. European Union Directives of 2006 provides recycling targets (as a percentage of average weight) for different battery chemistries. Japan addresses the battery recycling through its Law for the Promotion of Effective Utilization of Resources. On the recycling methods and technologies, Chinese battery recyclers have adopted hydrometallurgy largely and adhere to the NEV regulations whereas European battery recyclers have extended their existing pyrometallurgical processes and incorporated hydrometallurgy to refine their products. The paper will present the details of each of the countries intiatives to address the recycling of its batteries. References [1]. Harper, G., Sommerville, R., Kendrick, E. et al. Recycling lithium-ion batteries from electric vehicles. Nature 575, 75–86 (2019). https://doi.org/10.1038/s41586-019-1682-5 [2] IEA, 2021. Global EV Outlook, s.l.: IEA.

Resume : Renewable energy is the most desirable form of energy necessary for maintaining clean and green environment. The dream of using Sun light for meeting our energy demands is one of the key areas which researchers have been trying to accomplish since the discovery of photoelectric effect in 1905. Over time, dye sensitized solar cells (DSSCs) have gained attention of scientific community due to their cost-effectiveness and good performance under ambient light conditions. Other advantages of DSSCs include fabrication possibility on flexible substrates, solution processability and low toxicity. Present investigation focusses on two novel dyes based on the Donor-π-Acceptor (D-π-A) architecture, which can be used in DSSCs. The designed novel dyes are MS1 [anthracene-thiophene-pyridine] and MS2 [coronene-thiophene-pyrimidine]. In these dyes, anthracene and coronene are donors, pyridine and pyrimidine are acceptors, whereas, thiophene acts as the bridging unit. The dye molecules have been optimized under the framework of Density Functional Theory (DFT) using B3LYP/cc-PVDZ in Gaussian 16W software package. The TD-DFT calculations were performed at B3LYP/cc-PVDZ theory level to check the absorption maxima in both the dyes. TD-DFT results confirm that the absorption regions of these dyes lie in the red portion of visible spectrum. The maximum absorption wavelengths for MS1 and MS2 have been found to be 980 nm and 666 nm respectively. Other photovoltaic parameters calculated for analysis are light harvesting efficiency, charge injection energy, dye regeneration energy and open circuit voltage. Keywords: Donor-π-Acceptor, DFT, TD-DFT, Photosensitizer, DSSC.

Resume : Perovskite based solar cells present different advantages compared to other technologies, thanks to their numerous assets. Recently, this technology is attracting the interest of researchers all around the world with the aim of deepening knowledge and overcoming obstacles that hinder its large-scale use. In this way, numerical simulation of tandem perovskite based solar cells is performed for in depth analysis aiming to understand effect of top cell active layer and to improve tandem device performance. The simulation is based on experimental data for several layers and allows to predict nearly the efficiency of tandem device. The effect of metallic nanolayers on tandem device performance is also investigated. It is found that the performance of the best cell is higher than that of single solar cells.

Resume : Perovskite solar cells (PSCs) are a novel photovoltaic technology that is highly efficient and low-cost, making them a promising candidate in the solar industry. However, the long-term stability of PSCs inhibits their commercialization prospects. Carbon-based, mesoscopic PSCs have been shown to have increased stability due to the moisture- resistant nature of the carbon layer and resistance to ion migration.1 We fabricate and characterize carbon-based hole-transport-material-free perovskite solar cells composed of a mesoscopic scaffold of metal oxides that is screen printed and infiltrated with a perovskite precursor solution.2 After fabrication, we gather data from IV curve, laser beam induced current (LBIC), and external quantum efficiency (EQE) measurements with long-term light soaking. The LBIC data allows us to analyze spatial dependence of efficiency, and we correlate this with the performance data from the IV curves and EQE measurements.3 These findings will help us investigate degradation pathways and common defects, yielding further understanding of device stability and long-term prospects. This work is completed with the help of David Tanenbaum, Adam Dvorak, and Dan Tan. References [1]. Chen H., et al., Advanced Materials 2017, 29, 1603994. [2]. De Rossi, F., et al., Energy Technology 2020, 8 (12), 2000134. [3]. Dvorak, A., et al., 2020 47th IEEE Photovoltaic Specialists Conference (PVSC) 2020, 1171.

Resume : The Sun is known to be the most powerful source of energy. Solar cells are devices that convert absorbed light into electricity and silicon solar cells are currently the most used technology to do that. However, it has its own drawbacks and other solar cell technologies have been developed. Perovskite solar cells (PSCs) have recently emerged as a promising technology for the further cost reduction of the energy production from the sunlight. However there are several obstacles that need to be addressed for it to see a widespread use. One of them is the use of expensive hole-transporting material (HTM) such as Spiro-OMeTAD to obtain efficient devices [1]. Therefore, there is vigorous research for cheaper and simpler methods for the synthesis of organic semiconductors. Carbazole and fluorene derivatives are among the most popular structural building blocks, used for the construction of organic HTMs [2]. In this work we synthesized Spiro-OMeTAD analogues and simpler „half‟ structures, containing carbazolyl- and methoxyphenylchromophores. All synthesized HTMs exhibit good thermal stability (up to 400 °C). Almost all new HTMs showed Tg significantly exceeding 100 oC. According to DSC data the polymerization temperatures can be observed for materials V1241 and V1274. These materials have vinyl group at central moiety. Polymers exhibit much better film-forming ability, than small-molecular organic HTM’s and high hydrophobicity [3]. Unfortunately, these materials are not suitable for production of solar cells with an n-i-p structure due to their high polymerization temperatures. Nevertheless, other compounds have amorphous state, which is important for homogenous films forming. The ionization potential (Ip) of target materials is in range of 4.85‒5.02 eV which is suitable for use target materials in perovskite solar cells. From obtained data it is evident that all of materials are suitable for use in perovskite solar cells except for V1241 and V1274. The PCE of the most efficient n-i-p PSCs perovskite device containing Spiro-OMeTAD analogue V1267 have reached 18.3 %. Furthermore, “half” structures with methoxyphenyl/carbazolyl fragments show good long-term stability and outperform Spiro-OMeTAD. References [1]. Saragi, T., P., I., et al. Chem. Rev., 2007, 107, 1011. [2]. Liu, X., et al. Sustainable Energy Fuels, 2020, 4, 1875. [3]. Sun X., et al., ACS Appl. Energy Mater. 2020, 3 (11), 10282.

Resume : The limitation of solar power generation is its intermittency, and thus the efficiency produced by solar cells are different during the day and nighttime. High amounts of electricity can be generated only when the sun shines on photovoltaic panels. On the other hand, the solar energy resource is the most stable one since the beginning of life on Earth, however the main difficulties concern its efficient transfer and storage. That can be achieved by a combination of solar cells with storage devices such as batteries or supercapacitors. This type of system is usually named photo-storage devices. In this work, photo-storage devices were built by combining the recent solar cell technology based on perovskite materials as energy conversion part and supercapacitors based on activated carbon as energy storage part. The advantage for the combination of both types of devices consists in the simultaneous use of a carbon layer as electrode for the supercapacitor and counter-electrode and/or hole transport layer for the perovskite solar cell (PSC) [1]. To obtain the graphite-type activated carbon, biomass materials, as widely available renewable sources, were used. Thus, coconut shell waste was used to obtain activated carbon using safe water and steam activation processes. Among the different samples prepared, the activated carbon obtained by steam activation showed high surface area (1998 m2 g-1) and, in contact with ionic liquid (MPPyFSI), displayed an outstanding symmetric double layer supercapacitor storage capability with 10 times higher specific energy (33.3 Wh kg-1) than in the presence of aqueous H2SO4 electrolyte (3.3 Wh kg-1). Due to their high stability and high efficiency, these supercapacitors were integrated with PSCs to construct photo-storage devices [2]. Sustainable, ultra-low-cost biomass materials as electrode material for photo-supercapacitors are very interesting for real industrial applications. Long-term stability and influence of I-V hysteresis on the evaluation of photo-supercapacitors during the photo-charging/discharging processes will be also discussed. Acknowledgments: This work benefited from State assistance managed by the National Research Agency under the “Programme d’Investissements d’Avenir” (ANR-19-MPGA-0006), and supported by ELORPrintTec (ANR-10-EQPX-28-01). References: [1] N. M. Keppetipola, et al., Sustainable Energy Fuels, 2021, 5, 4784-4806. [2] N. M. Keppetipola, et al., RSC Advances, 2021, 11(5), 2854-2865.

Resume : The microporous silicates are interesting as ionic conductors, molecular sieves and ion exchangers is largely associated with the discovery of new mineral species. The largest alkaline massifs of the Kola Peninsula (Khibiny, Lovozero, Kovdor) allow a record number of finds of new and rare minerals, and a comprehensive study of these minerals makes it possible to identify new promising materials. In this paper, we present the results of studying the migration paths of alkali cations using modern methods of theoretical modeling (the Voronoi method [1], the tiling method [2], BVSE [3]) for the mineral groups keldyshite, eudialyte, alluadite, lithidionite, and sitinakite. Geometric-topological analysis (Voronoi method) and the tiling method were carried out using algorithms implemented in the TOPOSPro software package (https://topospro.com/) [4]. The search for ion migration channels in the framework of a crystal structure includes an analysis of the geometric characteristics (radii of voids and channels) calculated in the framework of the theory of partitioning the crystal space into Voronoi polyhedra. Calibration of geometric characteristics based on the analysis of known ionic conductors of this type makes it possible to determine potential solid electrolytes for which ionic conductivity has not been previously studied. The topological analysis of crystal structures includes determining the topological type of the base net, searching for inorganic compounds with the same type of base net, and constructing tiling. The base net is a graph whose vertices are the centers of gravity of the structural units of the crystal. In the case of silicates, the structural units are SiO4 tetrahedra and MO6 octahedra. Fig. 1. Base net (a) and map of Na+-ion migration in the form of layers (001), obtained using the Voronoi method (b) for the crystal structure of keldyshite. The definition of the topological type of the net is carried out using the TOPOSPro complex or the TopCryst web service, which contains data on about 190 thousand types of nets. The theory of tilings, which is actively used to study crystal structures thanks to the works of M. O'Keeffe [2], makes it possible to study the smallest cavities in inorganic frameworks, with which the entire crystalline space can be tiled. Eudialyte group minerals are of significant scientific and industrial interest as important concentrators of rare and strategic elements. Twelve theoretical framework types of the eudialyte structure were studied, taking into account all possible heteropolyhedral substitutions. Based on topological analysis, it was found that Na+ ions can migrate along six- and seven-membered rings, while all other rings are too small for migration. For eight types, migration and diffusion of Na+ ions are possible at standard temperature and pressure, while in four other frameworks, cells are connected by narrow windows and, as a result, Na+ diffusion in them is hindered under environmental conditions. But may be possible at higher temperatures or in long geological processes under mild conditions. Sitinakite (IONSIV-910/1) and ivanyukite (SIV) are considered as materials for sorption of radioactive isotopes 90Sr and 137Cs and conversion of high-level radioactive waste into low-level one. The crystal structure of sitinakite and its La-exchange form were investigated using theoretical modeling methods. It was established that all cations outside the framework (K+, Na+) have a three-dimensional system of migration paths. This means a high level of probability of free migration of all extra framework cations in the sitinakite structure. It should be noted that the migration map for Na+ has more branched paths than the migration map for K+ cations. The tiling for the basic sitinakite net consists of four types of tiles. Three of them (t-kzd, t lov, t cub) are quite small and play the role of gluing large tiles together (Fig. 2). Tile [48.66.82] is a new topological type, not previously described in the existing database of tiles (compiled on the analysis for all zeolites http://iza-structure.org). This tile is a large cavity that can hold large cations such as potassium or lanthanum. Na+ cations are predominantly located along the edges of this cavity in the center of 6-membered rings. Fig. 2. a) Topological analysis of cavities in the crystal structure of sitinakite. b) Results of BVSE analysis in KNaCa(H2O)Si4O10 calcinaksite. The maps of migration of sodium cations for keldyshite and parakeldyshite obtained using the Voronoi method are layers that ?penetrate? all crystallographic positions of sodium (Fig. 1). Tiling consists of one topological type of tiles with the formula [43.63]. Sodium atoms are located inside the cavity [43.63], however, since there is more sodium in parakeldyshite, each tile in its structure [43.63] is ?filled? with sodium, while in keldyshite it is only half of the tiles [5]. Na+ cation migration maps were constructed for four types of frameworks of litidionite group minerals: litidionite KNaCuSi4O10, manaksite KNaMnSi4O10, phenaksite, KNaFeSi4O10, and calcinaksite KNaCa(H2O)Si4O10. It has been established that for these structures the 1D migration map is the most probable. BVSE calculations for minerals of the litidionite group show that the structures cannot be K+ ion conductors, since potassium migration maps have high diffusion barriers. Na+-ion transport occurs predominantly along 1D migration maps. The results obtained using theoretical modeling were compared with experimental data. The correlations found will form the basis of future work on the search and design of new promising ion-conductive and ion-exchange materials. This work has been supported by the grants the Russian Science Foundation, RSF (Project No. 22-23-00355) References 1. Blatov V.A., Shevchenko A.P. // Acta Crystallogr. 2003. V.A59. P. 34., doi: 10.1107/S0108767302020603. 2. Blatov V.A., Delgado-Friedrichs O., O?Keeffe M., Proserpio D.M. // Acta Crystallogr. 2007. V.A63. P.418, doi: 10.1107/S0108767307038287. 3. Wong L.L., Adams S. et al. // Chem. Mater. 2021. V.33. P.625, doi: 10.1021/acs.chemmater.0c03893. 4. Blatov V.A., Shevchenko A.P., Proserpio D.M. // Cryst. Growth Des., 2014. V.14. P. 3576, doi:10.1021/cg500498k. 5. Kabanova N.A., Panikorovskii T.L. et al. // Crystals. 2020. V.10(11). P.1016., doi.org/10.3390/cryst10111016.

Resume : Enhancing stability and efficiency are the most significant challenges facing the formamidinium lead iodide (FAPbI3) perovskite solar cell device. Herein we study the impact of different cations dopants; cesium (Cs), guanidinium tetrabutylammonium (TBA), guanidinium (GA), methylammonium (MA) in the formamidinium lead iodide properties. The dopant impacts the film coverage grain size and the stability of the desirable perovskite phase -FAPbI3. The films prepared using cesium had fewer pinholes and large grains compared to other films prepared with other dopants tetrabutylammonium, guanidinium, methylammonium. The FAPbI3 grains, with about 400nm, are highly oriented along the (110) direction. Photoluminescence analyses highlight the impact of the dopant type on the surface passivation of deposited FaPbI3 films. We report the simulation run for the case of Cs doped FAPbI3, where Voc=0.86 V, Jsc=26 mA/cm², FF= 86 % and eta=19 %; and for FAPbI3 pure, Voc=0.887 V, Jsc=14.11 mA/cm², FF=83.72% and eta=12.42%. In perovskite-based devices using cesium doped FAPbI3 as an absorber, it was more stable with higher efficiency. This paper also allows the development of a new, reliable production system for PSCs.

Resume : Everything has a temperature, and everything making a work produce heat. Thermoelectrics, concerning the conversion between heat and electrical power, can play a crucial role in meeting the future energy challenge. Some industrial sites and, lately, some e-cars can partially recycle the produced heat, shrinking their energy consumption. The technology exists, but it is mainly used to recover the high-temperature heat, even if most of the waste is at a temperature lower than the water boiling point, 100 °C. Therefore, in planning a sustainable future, such waste heat has to be used. However, the thermoelectric generator’s high price and, in some cases, low efficiency limit the spread of this technology. Increasing the efficiency is hard, and it is unlikely achievable with conventional compounds. Moreover, tons of active materials should be efficiently produced to make thermoelectric technology economically advantageous. Hybrid perovskites can meet all these demands because they are cheap, and it is easy to produce compact thin films. They have been proposed for thermoelectric applications as they prove to have very low thermal conductivity. However, doping is required to enhance electrical conductivity to achieve high thermoelectric performances. Here, we propose a novel synthesis for zero-dimensional methylammonium bismuth iodide (CH3NH3)3Bi2I9 single crystals, thin films, and pellets. Bismuth-based hybrid perovskite has advantages over the more famous lead-based perovskite for higher stability and nontoxicity. The bismuth-based hybrid perovskites were synthesised in air with common and cheap solvents to keep production costs low. The synthesised materials have been characterised by UV-Vis, μ-Raman, XRD, XPS/UPS, and EDX spectroscopy measurements and SEM to study their morphology. Methylammonium bismuth iodide has been doped with tin and sulphur to increase the carrier concentration and mobility. The study of the fundamental properties allows us to tune the thermoelectric features. The response to thermal stimuli provides outstanding results. The complete physicochemical characterisation of the bismuth-based hybrid perovskites designed by us will be presented, together with some preliminary results on their thermal response.

Resume : In the present era of the Internet-of-Things (IoT), the increased demand for alternative and innovative ways of power supply has led to boost the Wireless Energy Transfer (WET) field, as well as the constant improvement of the processes of Energy Harvesting (EH)[1]. Despite the majority of the most common WET systems relying on magnetic induction, these tend to have a reduced efficiency for long-distance applications thus, the development of new systems for this type of scenario is essential[2]. Herein, we demonstrate the concept of combining an EH process, i.e., thermoelectricity (TE), with the WET through a high-power laser beam. A radial design for the TE device was chosen to create a temperature gradient from the inside to the outside of the circle through the incidence of a laser beam in its centre. Screen-printing was applied to fabricate the device, in a two-step process – electrical contacts and thermoelectric stripes. Commercial silver ink was used for the electrical contacts, and a TE ink was developed. A polymer matrix of PVA (Polyvinyl Alcohol) doped with phosphoric acid (16.4%wt) mixed with PEDOT:PSS (poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate)) (16.4%wt) was combined with commercial Bi-Te microparticles (67.2%wt), adapted from a previous study[3]. Transport properties were analysed for the TE microparticles and the printed film. The microparticles present a Seebeck coefficient of 168µVK-1 and electrical conductivity of 2379.05Sm-1, thus leading to a Power Factor (PF=S2σ) of 67.15µWm-1K-2. Regarding the TE film, the polymer incorporation caused a decrease in both properties (S=33µVK-1 and σ=7.32Sm-1), having a PF of 7.97µWm-1K-2. The developed device was characterised under vacuum at room temperature, with an incident laser beam with a wavelength of 1500nm and a variable power (0.5–2W). The presence of a light collector in the centre of the device was considered to increase the output, and a comparative performance analysis was carried out. Commercial carbon ink was printed by screen-printing to obtain the light collector. A maximum output voltage of 16 mV and a maximum power density of 25μWm-2 were achieved with the collector and a laser power of 2W. The temperature and pressure effect on the output was also evaluated, and an increase of 25% and 230%, respectively, was observed. This promising technology reveals to be a possible alternative for energy generation in remote places. Financial support from UIDB/04968/2020, and NORTE-01-0145-FEDER-022096 from NECL is acknowledged. MMM, ALP, MR and AMP thank the funding from the European Union’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 863307 (Ref. H2020-FETOPEN-2018-2019-2020-01). MMM thanks FCT for grant SFRH/BD/144229/2019. [1] A. Raj et al., Journal of the Electrochemical Society 165, B3130–B3136 (2018). [2] C. Jiang et al., ACS Nano 15, 9328–9354 (2021). [3] A.L. Pires et al., ACS Applied Materials & Interface 11, 8969–8981 (2019).

Resume : In parallel with the increasing energy demand in recent years, cheap energy production with renewable resources is expected from solar cells. Over the years, solar cells have been made from many other semiconductor materials with various device configurations. On the other hand, intensive research is carried out for new materials in order to reduce the cost of photovoltaics based on inorganic semiconductor technology and increase efficiency. In organic photovoltaics, different organic materials are used to increase efficiency. Furthermore, effects of a chemical additive into polymer/fullerene bulk-heterojunctions have been investigated by several groups. Using chemical additives results in significant improvement of the efficiency of organic solar cells and it is rather simple method as compared to other treatments. In the field of materials, when order and mobility are required, it is natural to think about liquid crystals. By using liquid crystals (LCs) one can, in principle, control order in the bulk and at interfaces, from molecular to macroscopic distances. Because of their liquid-like character they can self repair structural defects. Large single domains can be obtained by simply thermal annealing. By easily tuning parameters such as concentration or temperature and irradiation with polarized light or surface alignment layers, one can orient molecules inside these large domains. Schmidt-Mende and coworkers reported a methodology of controlling nanostructured p-n junction in organic photovoltaics using discotic liquid crystal molecules and they have reported that using liquid crystal molecules, charge transport in organic photovoltaics could be enhanced [1]. Liquid crystals are organic materials that attract attention with their electro-optical properties. Although the use of liquid crystal materials in the field of photovoltaics has gained momentum in the last decade, there are still a limited number of studies in the field, including the use of commercial liquid crystals. In this study; It is aimed to use liquid crystal (LC) organic molecules to be synthesized by our group in organic solar cells. The photovoltaic properties of organic solar cells with and without liquid crystal (LC) additives are compared. Especially for the OPV applications, LCs could play an important role. References [1] L. Schmidt-Mende, A. Fechtenkotter, K. Mullen, E. Moons, R. H. Friend, J. D. Mackenzie, Science 2001, 293, (5532) 1199 .

Resume : India has a strong commitment towards climate change mitigation actions and aiming for net zero status by 2070. Electric vehicles are reshaping our transportation sector by stepping towards cutting carbon emissions and in turn mitigating the alarming climate change. Integrating electric vehicles with renewable energy will successively result in the rapid growth of renewable energy industry and ensuring net zero emissions. Currently in India, there is no mandate for charging electric vehicles with renewable energy unlike few other countries who have taken steps towards green power-based charging policies. Even though there are many schemes and policies rolled out in India for promoting renewable energy for achieving India?s ambitious renewable energy targets and several policies exist for promoting e-mobility there is no direct linkage established so far. There exists a large potential in combining the renewable energy with vehicle charging in India. The wide range of green power procurement options available in India can be effectively utilized to ensure green charging. Introducing consumer specific policies and schemes will not only attract many players into the industry, but also ramp down the charging tariffs in the long run. ?Open Access? procurement of renewable energy makes it eligible for the consumers with large energy requirements to procure power through open access which gives the consumers, the freedom to get power from desired parties at attractive tariffs. There are few other options within the power market instruments in India at present by which renewable energy-based electricity can be procured from a far-flung location. However, certain challenges still exist in India for ensuring the electricity used for e-mobility charging come from renewable energy sources. This paper briefly describes few examples and discusses key measures and models successfully implemented in few countries in this regard. The paper identifies the specific challenges in India and suggests few measures which can be combinedly implemented along with the existing measures in the country. References [1]. https://www.niua.org/iscfip/compendium/project/solar-energy-based-electric-vehicle-charging-infrastructure-city-nagpur [2]. https://evreporter.com/options-to-tie-solar-energy-with-ev-charging/ [3]. https://www.betterenergy.org/wp-content/uploads/2020/10/Solar-Power-Electric-Vehicle-Charging-.pdf

Resume : EQE measurements have been carried out in perovskite single and tandem structure at different voltage/light biases and chopping frequencies in an attempt to investigate the impact of those factors on the EQE of the devices. The EQE measurements of perovskite/Silicon tandem device present more challenges compared to EQE measurement procedures of the single-perovskite devices due to the series connection of junctions inside the tandem structure. Therefore, detailed investigation of the voltage/light bias is required. Voltage bias studies have been carried out in perovskite single junction devices as well. The impact of chopping frequency has been studied in a perovskite tandem device through time response analysis method to establish the appropriate frequency for EQE measurements of perovskite devices. Voltage bias EQE dependent measurements demonstrates no change at different voltages in both perovskite single and tandem structures indicating that voltage does not have an impact during those studies. Chopping frequencies in the range from 5-70 Hz have been applied on perovskite/Si tandem cells. For that purpose, an initial quantitative time response analysis was undertaken using oscilloscopes followed by complete EQE measurements at various chopping frequencies. The complete EQE measurements during that procedure have been studied at two different wavelengths to cover the response of both junctions in the tandem device. No EQE measurement dependence on chopping frequency was detected in the measurements indicating that the frequency is not an issue during the EQE measurements of perovskite tandem solar cells. Finally, light bias measurements have demonstrated that the minimum light bias conditions for measuring perovskite top in the perovskite/Si tandem configuration are 13W/m2. However, this value depends strongly on the performance and technology of the perovskite under test and more studies should be implemented to extract more reliable results. References [1] Paraskeva V., Hadjipanayi M., Ho-Baillie A., Daukes N.E., Zheng J., Georghiou G.E." Proc. 36th EUPVSEC 2019, 772-774, ISBN: 3-936338-60-4

Resume : An improved light harvesting organic-inorganic nanocomposite material was obtained by coupling a judiciously developed green-orange absorbing bichromophoric organic salt [R6G][HFl] and UV-blue absorbing TiO2 QDs. The designed bichromophoric salt is synthesized using a biphasic metathesis reaction and the nanocomposite [R6G][HFl]-TiO2 is then obtained by single phase overnight stirring of the two components in an optimized ratio. The synthesized nanocomposite results in further broadening of absorption spectrum ranging from UV to NIR with the peak approximately matching the solar irradiation spectrum and demonstrate enhanced absorptivity thereby capable of harvesting the major part of the solar emission. The nanocomposite demonstrates a perfect molecular as well as HOMO-LUMO and valence band?conduction band alignment which enables energy transfer from TiO2 to [R6G][HFl] and charge transfer between duo as evident from steady state and transient photoluminescence studies. White light irradiation of the nanocomposite film exhibits 450 times higher photocurrent than that of the bare TiO2 film. The slow photocurrent decay time of 46 sec confirms that a generous amount of photo generated carriers harvest in the composite sample. This unique nanocomposite structure demonstrating spectral broadening along with charge transfer results in extraordinarily improved photocurrent and photoresponse thereby rendering [R6G][HFl]-TiO2 nanocomposite an excellent potential active material for a solid state TiO2 based Heterojunction Solar Cell (HJSC). Efficiency of this nanocomposite based HJSC was found to be the highest (4.4 %) among the various other layer by layer structured devices thereby presenting a simplified cell fabrication technique by excluding the necessity of usual layer by layer dye deposition on TiO2 followed by their optimization for best efficiency. Thus, this study presents a thoughtfully designed device ready perfect active material for a TiO2 based HJSC exhibiting good competence. References [1] Dutta, K., et al., Colloids and Surfaces A 2020, 597, 124707. https://doi.org/10.1016/j.colsurfa.2020.124707

Resume : Thin film photovoltaics, represented by established CIGS, CdTe and a-Si:H, and the newest addition of the perovskites, always held the promise of good device performance with the benefit of low production cost and material consumption. These technologies take advantage of the high optical absorption cross section of the direct band gap semiconductors involved, requiring shorter optical path for efficient absorption of light. Therefore, devices are thin, some even flexible, contrary to classic indirect band gap semiconductor silicon. Additionally, the mentioned materials do not depend on long-range order for efficient exciton dissociation or charge transport. This enables low-cost device manufacturing methods, away from expensive single crystal growth, e.g. evaporation, slot-die coating or printing. Still, despite these advantages of thin film PV, crystalline silicon modules dominate the market. One reason, which cannot be underestimated, is the issue of metastability of thin film PV. This is because the addressed beneficial characteristics of the material, also bares its greatest risks. Grain boundaries, hetero-composites, mobile doping ions, interlayer diffusion, leave several opportunities for a PV device to change its optical and electronic properties over time, during operation or simply by aging. The occurring phenomena and their degree may depend on climate, triggered by light intensity, temperature, humidity, or on the grid potential in the field. Some effects are reversible, some are not. To account for metastability, technology-specific standard preconditioning protocols are in place, designed to bring commercial thin film modules into an optimum state, to allow comparison. Often enough, this raised conflicts. While it is in the best interest for manufacturers that a sample module from the field shows at its best in the lab after transport and standard preconditioning, this may not help customers, who wish to prove their modules ran permanently below the expected power output. Our goal is the development of new standard preconditioning protocols, which take the pre-transport-state of an individual module into account and reinstate it as close as possible. This is not a trivial task. Key parameters are required, which serve as marker for the condition of a thin film module in the field, to recover at preconditioning after transport. Identification of such a reliable parameter, requires thorough knowledge of potential solar cell internal defects, diffusion and degradation processes and how these show in in such modules via field accessible methods, such as photo-IV curves or EL-image-based resistance measurement. Unfortunately, correlation of visible effects with associated device-internal processes is often limited, because device architecture, compound composition, heat and gas treatments, which all affect these, are company secret, depend on manufacturer, model, production year or even the fabrication site. Working the black box.

Resume : Organic, inorganic halide perovskite solar cells have been largely investigated thanks to their outstanding photovoltaic performances. They have become a competitive alternative to the traditional Si cells dominant in the market. The cell’s performance and stability are affected on one hand by the extrinsic conditions (thermal stress, moisture, and others), and on the other hand the intrinsic properties of the perovskite layer itself, which in turn depend on the chemical composition. In our work, we sought to point up the different structural, morphological, and optical properties of the active layer as a function of the chemical composition: FA, Ma, and Cs for the cation site and I or Br for the anion site. The incorporation of a large cation FA with different substituted halide compounds (I or Br) tunable the bandgap from 1.48 to 2.42 eV, providing a whole range of colored perovskites.

Resume : Perovskite solar cells (PSCs), as the most well-known emerging thin-film photovoltaics (PVs), attracted large scientific and technological interest due to their unique properties (e.g., high efficiency, cost effective printable fabrication and band gap tuning) that allow for different applications. The halide perovskite absorber has long diffusion length and long minority carrier lifetimes, high dielectric constant and permit a fast charge separation process. Nevertheless, PSC degradation, stability against light and thermal stresses, high quality film and optimal thickness especially for large scale deposition on module size are important aspects that still need to be properly address. In our activities, several approaches to reach efficient stable perovskite solar module have been developed. In 2017, 350 h light stable perovskite solar module fabricated out of glove box was demonstrated by using crystal engineering (CE) method and reaching an efficiency on 10.1 cm2 active area (AA) of 13% and 12.1% using Spiro-OMeTAD and Poly(3-hexylthiophene-2,5-diyl) P3HT as hole transport materials (HTM), respectively. 1 Later, by identifying a specific doping strategy of the P3HT polymer, a 13.3% efficient large area module (43cm2 AA) was fabricated. A thermal stability of T80>500 h at 85°C and a T90=100 h stability against continuous light soaking and (>1500 h) shelf life stability was achieved for the device.2 Moreover, by considering a scalable CE approach based on solution heteroepitaxial growth of stable mixed cation/anion hybrid perovskite thin film under ambient conditions, an efficiency of 18.4% for small area (0.1 cm2), 16.5% on larger area (1 cm2) cells, and 12.7% and 11.6% for fully blade-coated modules with an active area of 17 and 50 cm2, respectively, was achieved.3 In 2019, an efficiency above 20% on small area and 17% on large area module (43cm2 AA) maintaining above 90% of the initial efficiency after 800 h thermal stress at 85 °C was demonstrated by exploiting polaron arrangement of tuned polymeric hole transport layer4. This results was recently improved with the fabrication of a 45.6cm2 AA module with an efficiency of 18.45%.5 In addition, by using an universal approach for layer-by-layer deposition of 3D/2D perovskite films with zero waste permitted to fabricate large area cells with efficiency of 19.55% and thermal stability at 85 °C of T90=1000 h and 18.8% perovskite solar module.6 In the present work, extending the reported strategy by using novel stable 2D perovskite passivation layers, we report on the fabrication of high efficiency, stable perovskite solar module reaching and efficiency of 20.2% and more than 1000 hours thermal and light stability. References: 1. Yaghoobi Nia, N., Zendehdel, M., Cinà, L., Matteocci, F. & Di Carlo, A. A crystal engineering approach for scalable perovskite solar cells and module fabrication: a full out of glove box procedure. J. Mater. Chem. A 6, 659–671 (2018). 2. Yaghoobi Nia, N. et al. Doping Strategy for Efficient and Stable Triple Cation Hybrid Perovskite Solar Cells and Module Based on Poly(3‐hexylthiophene) Hole Transport Layer. Small 15, 1904399 (2019). 3. Yaghoobi Nia, N. et al. Solution-based heteroepitaxial growth of stable mixed cation/anion hybrid perovskite thin film under ambient condition via a scalable crystal engineering approach. Nano Energy 69, 104441 (2020). 4. Yaghoobi Nia, N. et al. Beyond 17% stable perovskite solar module via polaron arrangement of tuned polymeric hole transport layer. Nano Energy 82, 105685 (2021). 5. Zhang, H. Darabi,K. Yaghoobi Nia,N. et al. A universal co-solvent dilution strategy enables facile and cost-effective fabrication of perovskite photovoltaics. Nat. Commun. 13, 89 (2022). 6. Zendehdel, M., Yaghoobi Nia, N., Paci, B., Generosi, A. & Di Carlo, A. Zero‐Waste Scalable Blade‐Spin Coating as Universal Approach for Layer‐By‐Layer Deposition of 3D/2D Perovskite Films in High Efficiency Perovskite Solar Modules. Sol. RRL (2021). doi:10.1002/solr.202100637

Resume : The interest towards abundant and renewable energy sources is rapidly increasing due to the risk anticipated by climate change. Zinc phosphide (Zn3P2) is the ideal candidate as material for photovoltaic applications thanks to its direct bandgap, earth-abundance, and optoelectronic characteristics[1], although it has not been extensively studied due to limitations in the fabrication of high-quality layers. It is possible to overcome these factors by growing the material into nanoscale objects, exploiting the selected area epitaxy approach (SAE), opening up new elastic strain relaxation mechanisms and minimizing the interface area [2]. Here we present our latest results for Zn3P2 nanowire structures epitaxially grown on InP substrates with SAE. We have explored different substate/nanowire orientations to obtain a comprehensive picture of the main mechanism involved during the nanostructures growth. By combining aberration corrected scanning transmission electron microscopy in high angle annular dark field (HAADF-STEM) mode, with 3D atomic modelling and STEM image simulation we could recognize the presence of two stable rotated crystal domains coexisting in the same nanowire structure. We deeply investigated the defects’ nature and structure to address their formation mechanism. With the help of DFT simulation we could also explore the effects reflected in the Zn3P2 nanowires‘ physical and electronic properties, in order to comprehensively study the final device performance of the synthetized material towards solar cell application [3]. References [1] G. M. Kimball et al. Appl. Phys. Lett., 95, 112103 (2009) [2] S. Escobar Steinvall et al. Nanoscale Advances 2020, 3, 326. [3] M. C. Spadaro, et al. Nanoscale 2021, 13(44), 18441–18450.

Resume : Perovskite solar cells (PSCs) have become a major object of interest in the field of photovoltaics during the last decade. Over time this new technology has managed to demonstrate outstanding results in the power conversion efficiency (PCE) exceeding 25 % certified by the NREL [1]. In most of the n-i-p structured PSCs organic semiconductor Spiro- OMeTAD is used as the state-of-the-art benchmark for hole transporting materials (HTMs). However, due to its high cost, complicated synthesis, and high-purity sublimation-grade requirement it is improbable to use Spiro-OMeTAD for commercial purposes [2]. Here, a new series of low-cost enamines were functionalized via single-step synthetic procedure, which does not involve costly catalysts. Moreover, significantly simplified product workup and purification may greatly reduce the cost of final products. To investigate photoelectrical properties of synthesized enamines hole drift mobility (μ) and ionization potential (Ip) were measured. Photoelectron spectroscopy in air method was used to measure ionization energy. Ip values of HTMs were found to be between 5.27 and 5.64 eV, therefore, all compounds are suitable for the application in the PSCs using perovskite with deep valence band. Xerographic time of flight technique was used to determine charge mobility of the investigated HTMs layers. Enamine V1435, containing triphenylamine central fragment, demonstrated the highest zero-field μ0 among the series, having the value of 2 × 10-5 cm2/Vs. n-i-p solar cells were fabricated with the device layout glass/ITO/SnO2/perovskite/HTM/Au to test novel compounds as HTMs. The most efficient device containing V1435 showed a champion efficiency of 20.1%, which is higher than PCE of the control device containing Spiro- OMeTAD (19.7%). This work confirms that straightforward enamine condensation chemistry is a promising method to achieve highly efficient PSCs. References [1] https://www.nrel.gov/pv/assets/pdfs/cell-pv-eff-emergingpv-rev211214.pdf [2] Rakstys, K., et al., Chemical Science 2019, 10, 6748-6769

Resume : The rapid growth of the role of renewable energy sources dictates new requirements for the stationary electrochemical energy storage devices [1]. Among them, redox flow batteries (RFBs) are regarded as a promising technology, since their advantages of excellent scalability, low cost, long lifetime, and safety. Today inorganic RFBs are penetrating the market [2], however, the replacement of inorganic materials with organic redox-active molecules may significantly accelerate the commercial implementation of this technology. In our work, we performed a comprehensive study for a group of novel organic materials based on aromatic amines with general formulas of NPh3RnBrm and N2Ph5RnBrm where R = -(OCH2CH2)2-OCH3. All the compounds demonstrated high solubility in MeCN (from >2.2 M up to complete miscibility), which can potentially enable outstanding specific capacities of organic RFBs approaching 134 Ah L-1; and one or two quasi-reversible electron transition processes with redox potential up to 0.6 V vs. Ag/AgNO3 reference electrode. RFB tests proved that the most promising systems are capable to exhibit 65% of maximum capacities and more than 95% Coulombic efficiency after 50 cycles [3]. In the next step, we synthesized and investigated novel phenazine derivative with oligomeric ethylene glycol ether substituents as promising anolyte material [4]. The designed compound undergoes a reversible and stable reduction at -1.72 V vs. Ag/AgNO3 and demonstrates excellent (>2.5 M) solubility in MeCN. A non-aqueous organic redox flow battery assembled using novel phenazine derivative as anolyte and substituted triarylamine derivative as a catholyte exhibited high specific capacity (~93% from the theoretical value), >95% Coulombic efficiency, 65% utilization of active materials and good charge-discharge cycling stability. To summarize, triarylamine-based and phenazine-based materials establish themselves attractive for future research: obtained redox potentials, high solubility, fast diffusion and kinetics opens promising future directions for their usage as organic cathodic and anodic materials for RFBs. This work was supported by the Skoltech-MIT Next Generation Program “Energy-dense and Durable Nonaqueous Redox Flow Batteries enabled by Flowing Solid-state Capacity Boosters”. Romadina Elena acknowledges the support provided by Haldor Topsøe A/S Scholarship 2021. References [1] Panwar N., et al., Renewable and Sustainable Energy Reviews 2011, 15 (3), 1513-1524. [2] Placke T., et al., Joule 2018, 2 (12), 2528-2550. [3] Romadina E., et al., JMC-A, 2021, 9, 8303-8307 [5] Romadina E., et al., ChemComm, 2021, 57, (24), 2986-2989

Resume : Photocatalytic solar fuel production provides a potential alternative to sustainable energy production. Whilst attention to date has focused on inorganic photocatalysts, carbon-based materials and organic semiconductors have emerged as potential low cost and efficient photocatalyst for hydrogen evolution, mainly due to the tunability of their properties through synthetic control.[1,2] This allow the design of families of materials with tuned opto-electronic properties by incorporating different building blocks.[1] The best performing systems are bulk heterojunctions nanoparticles prepared from a blend of conjugated polymer donor and non-fullerene small molecules acceptor, particularly due to their improved light absorption in the visible range.[2,3] Despite the efficient performance of the donor/acceptor bulk heterojunction photocatalysts for hydrogen evolution, the fundamental understanding of the photophysical processes that determine their performance remain limited. In this presentation, I will discuss the charge carrier dynamics of donor/acceptor heterojunction nanoparticles photocatalysts with different hydrogen evolution activity. Transient and operando photoinduced absorption spectroscopies, on timescales of femtoseconds to seconds after light absorption, were employed to monitor the kinetics of photogenerated charges and their correlation with photocatalytic performance. Differences between the function of Donor/Acceptor bulk heterojunction photocatalysts and single conjugated polymers photocatalyst will be discussed. These results can provide design guidelines towards efficient organic semiconductors photocatalyst. References [1]. Wang, Y.; Vogel, A.; Sachs, M.; et al. Nature Energy 2019, 4 (9), 746-760. [2]. Kosco, J.; Bidwell, M.; Cha, H.; et al. Nature Materials 2020, 19 (5), 559-565. [3]. J. Kosco, S. Gonzalez-Carrero, et al. Advanced Materials 2021, n/a, 2105007.

Resume : The power conversion efficiency of perovskite solar cells is approaching the Shockley Queisser limit, and therefore this technology is next to the commercialization stage [1]. Inexpensive and stable hole transporting materials are highly desirable for the successful scale-up. Most high performing devices generally employ expensive hole conductors that are synthesized via cross-coupling reactions which require expensive catalysts, inert reaction conditions and time-consuming sophisticated product purification [2]. In a quest to employ cost-effective chemistry to combine the building blocks, we explore enamine-based small molecules that can be synthesized in a simple condensation reaction from commercially available materials leading to an estimated material cost of a few euros per gram. The synthesized fluorene-based enamines exhibit a very high hole mobility up to 3.3 × 10-4 cm2 V1 s1 and enable the fabrication of perovskite solar cells with a maximum power conversion efficiency of 19.3% in a doped configuration and 17.1% without doping. In addition, both PSC systems demonstrate superior long-term stability compared to spiro-OMeTAD. This work shows that hole transporting materials prepared via a simple condensation protocol have the potential to compete in terms of performance with materials obtained via expensive cross-coupling methods at a fraction of their cost and deliver exceptional stability of the final device. References [1]. NREL, Photovoltaic Research: Best Research Cell Efficiency Chart, https://www.nrel.gov/pv/cell-efficiency.html, accessed 28 April 2020. [2]. Saragi, T. P. I., et al., Chem Rew. 2007, 107, 1011-1065.

Resume : Photovoltaic (PV) power generation, being a viable solar energy harvester, has a unique set of technical problems primarily because of operational difficulties. These involve; the sun as an intermittent energy resource and an over-heating issue. The excess PV heat is caused by the internal mechanism of the solid-state PV cells when some of the electrons of the higher frequency leave the conduction band on the incidence of solar energy. This phenomenon disrupts the reference temperature (25 °C) of the PV cells and the efficiency decreases because of the temperature coefficient. One alternative is to integrate the solar panel with a phase-changing material to regulate the temperature and use a thermal collector to take away the excess heat which can be used for other applications. This combined setup can bring environmental consequences because the whole cradle-to-grave life-cycle has further components because of the addition of thermal collector and energy storage through the usage of phase-changing material. Thus, it is desired to conduct a carbon taxing analysis aided by life-cycle carbon dioxide emissions along with an exergy analysis of the entire setup. The objective of this work is to conduct exergy and a carbon taxing analysis of solar photovoltaic thermal collector with phase-changing material. Within the method, a transient three-dimensional transport phenomena-based physical model is developed and solved iteratively using Gauss-Siedel formulation for the actual climate-based boundary conditions. Based upon the results of energy balance, the exergy assessment is applied to evaluate the exergy efficiency, sustainability index, and exergy destruction rate. The exergetic findings are combined with the life-cycle environmental emissions and the life-cycle economic costs to finally yield the exergy-based carbon taxes. The results have indicated that renewable energy resources can also have virtual environmental footprints. The machine can offer an exergy efficiency ranges from 13-17 %, the life-cycle carbon dioxide emissions range from 65 to 90 kg per year, Levelized cost of energy ranges from $3.09-$4.30 MXN/kWh, and carbon dioxide pricing based on energy and exergy balance ranges from $20.00-$32.00 MXN per year. It is concluded that such a multidimensional assessment can help in a better understanding of renewable energy systems based on a wide perspective. It is recommended to apply the multicriteria optimization method and social acceptability of such advanced machines from the stakeholders of the society. Reference R. Tariq, J. Xamán, A. Bassam, L. J. Ricalde, M.A.E. Soberanis, Multidimensional assessment of a photovoltaic air collector integrated phase-changing material considering Mexican Climatic conditions, Energy, 209 (2020), Article 118304, 10.1016/j.energy.2020.118304.

Resume : The efficiency of flexible perovskite solar cells (f-PSCs) has recently reached power conversion efficiency (PCE) as high as 19.5% [1]. Although still lagging behind their rigid counterparts, which in very short time have rocketed 25.2% efficiency [2], f-PSCs present several appealing features, such as bendability, conformability and high power-to-weight ratio [3], that make them good candidates for several applications, from consumer electronics to avionics and spacecrafts [4]. We present the synthesis of poly-3-hexylthiophene (P3HT)-derivated HTMs, embodying benzothiadiazole (BDT) moieties as electron-poor host. BDT was inserted along P3HT polymeric backbone, creating a donor-acceptor system able to promote the charge mobility throughout the HTM. Benzothiadiazole-modified P3HT (BTD-P3HT)[5] was used as hole transport material (HTM) in f-PSCs and led to PCE comparable to commercially available P3HT and showed improved stability under continuous illumination. It was also employed in 6×6 cm2 modules, delivering 6.9% efficiency on 16 cm2 of active area and demonstrating its feasibility for large area manufacture. Considering f-PSCs great potential for space application, we assessed their response to fast neutrons (i.e. with energies > 10 MeV), which represent one of the most severe forms of radiation at aircraft altitudes, in avionic, and space environments. Unencapsulated f-PSCs with either spiro-OMeTAD or BTD-P3HT as the HTM were exposed to under fast neutron irradiation, at fluence levels of 1.39 × 109 neutrons·cm-2 (almost 80 years of fast neutron exposure on the International Space Station) and 1.62 × 1010 neutrons·cm-2 (equivalent to 864 years of fast neutron exposure on the International Space Station). We observed that modified-P3HT cells experienced smaller voltage and current losses compared to spiro-OMeTAD but the overall performance suffered a much higher drop, as a consequence of a larger decrease in fill factor, ascribable to a sub-optimal perovskite/polymer interface. Nonetheless, spectral response and behavior at different light intensities of modified-P3HT cells suggest the polymer to be potentially more resilient than spiro-OMeTAD under fast neutron irradiation, once the perovskite/polymer will be improved[6]. References [1] K. Huang, et al., Adv. Energy Mater., 2019 (9) 1901419. [2] NREL, Best Research-Cell Efficiency Chart, 2021 https://www.nrel.gov/pv/cell-efficiency.html. [3] M. Kaltenbrunner, et al., Nature Materials, 2015 (14) 1032–1039. [4] J. Zhang, et al., Materials Today, (2020). [5] F. De Rossi, et al., J. Power Sources, 2021 (494) 229735. [6] F. De Rossi, et al., Nano Energy, 2021, 106879.

Resume : This work analyzes the energy contribution of a skylight [1] in a bedroom of an Andean rural dwelling located in San Francisco de Raymina (SFR) [2], at an altitude of 3700 masl in the Ayacucho Region at the south of Peru. To evaluate the influence of the skylight, indoor and outdoor parameters were recorded hourly before and after the installation of the skylight. Inside the bedroom, temperature, relative humidity and illuminance were recorded with the HOBO HO6-001-02 sensor [3], while outdoor parameters were recorded with a Davis Vantage Pro2 station [4]. The analysis was focused on two periods, considering period 1 during December 2014 (before the installation of the skylight) and period 2 during December 2015 (after the installation of the skylight). During period 1, the bedroom under analysis (bedroom D2) had the lowest temperature compared to the other spaces in the house (living room-kitchen and bedroom D1). During period 2, the temperature of bedroom D2 increased by 3.3 °C compared to period 1. The average temperature values obtained inside bedroom D2 were equal to 13.4 °C (December 2014) and 16.7 °C (December 2015). The thermal comfort during the day of bedroom D2 were also estimated, resulting in 39.5% (period 1) and 58.4% (period 2), determined using the neutral temperature (𝑇𝑛) according to Humphreys ( 1978) [5], 𝑇𝑛=11.9+0.534 𝑇̅𝑎; where 𝑇̅𝑎 is the mean annual SFR temperature and equal to 8.3 °C, resulting in 𝑇𝑛 equal to 16.3 °C. According to Preciado [6], since the average thermal oscillation of SFR is approximately (equal to 13.3 °C) between 13 °C and 15 °C, it corresponds to an amplitude of ± 3 °C. m2m program [7] was used to estimate the interior surface temperatures of the walls of bedroom D2, which are used in the energy balance. Using the inverse method, the air renewal rates were determined, so that the simulated temperature data approximated the experimental data. The daily energy contribution of all the interior surfaces that make up bedroom D2 were calculated from the energy balance considering the heat transfer from one surface to an adjacent fluid and the surroundings, heat transfer by air exchange, and solar gains. Finally, it was estimated that the skylight contributed with 37.1% (about 5.9 kWh) of the daily heat gains within bedroom D2. References [1]. Laouadi, A., et al., Building and Environment, 2003, 38, 117-127. [2]. Molina, J., in Facultad de Ciencias, Universidad Nacional de Ingeniería, Lima, 2016. [3]. Onset, HOBO State Data Logger: https://www.onsetcomp.com/products/data-loggers/h06-001-02/ [4]. Davis Instruments, Davis Vantage Pro2: https://www.davisinstruments.com/pages/vantage-pro2 [5]. Humphreys, M., Batiment International, Building Research and Practice 1978, 6, 92-102. [6]. Preciado, O., en IV Conferencia Latino Americana de Energía Solar (IV ISES_CLA) y XVII Simposio Peruano de Energía Solar (XVII- SPES), Cusco, 2010. [7]. G. Lefebvre, Energy and Buildings, 1997, 25, 19-30

Resume : The performance of organic–inorganic halide perovskite solar cells is approaching its practical limits, and conventional sandwich-architecture devices present inherent light absorption losses caused by the transparent conductive electrodes and charge selective materials. The use of back-contact electrode (BCE) architectures is an effective route toward higher device efficiencies. The BCE-based solar cells present its own challenges such as the difficulty on processing the electrodes with photolithography, the poor understanding of the underlying device physics or the defect tolerance of the electrode features. In this work we show different innovative approaches for improving the BCE solar cells that address the aforementioned challenges. By changing the interdigitated electrode geometry to honeycomb-shaped it is possible to minimize the effect of electrode damage during processing.[1] We show how the perovskite grain size is critical for the performance of BCE-based solar cells, with electrode distances much larger than sandwich devices.[2] The electrode materials are also a critical point in the device performance but in BCE there is a restriction on the available materials for deposition via sputtering or vacuum evaporation. Symmetric gold electrodes can be functionalized with dipole molecules to achieve charge separation of the perovskite,[1] otherwise metal oxides can be also introduced in BCE, we show how the charge extraction can be balanced by embedding mesoscopic architecture in the BCEs.[3] Finally, the scalability is one of the main limitations of the BCEs employing photolithography patterns in the resolution limits of the contemporary technology. We introduce a novel low-cost and scalable lithography method that enables to make larger area BCE solar cells with high efficiency. References: [1] X. Lin, S. R. Raga, A. S. R. Chesman, Q. Ou, L. Jiang, Q. Bao, J. Lu, Y.-B. Cheng, U. Bach, Nano Energy 2020, 67, 104223. [2] X. Lin, A. S. R. Chesman, S. R. Raga, A. D. Scully, L. Jiang, B. Tan, J. Lu, Y.-B. Cheng, U. Bach, Adv. Funct. Mater. 2018, 28, 1805098. [3] X. Lin, J. Lu, S. R. Raga, D. P. McMeekin, Q. Ou, A. D. Scully, B. Tan, A. S. R. Chesman, S. Deng, B. Zhao, Y.-B. Cheng, U. Bach, Adv. Energy Mater. 2021, 11, 2100053.

Resume : Perovskite Solar Cells (PSC) are a valuable contribution to renewable sources for satisfying our ever-growing energy demands. Stability is still one of the major bottlenecks on the development of this technology and its improvement is one of the main research goals in this field. For a solid advancement in stability endeavors is imperative to have a global consensus on the reported stabilities in the literature. 1 Also very important is to obtain information on the exact physical causes behind the device degradation along the stability studies, in order to target these processes and optimize the PSCs. The in operando characterization methods most commonly used today to track stability, such as current density–voltage (JV) and maximum power point tracking (MPPT), do not distinguish between different processes that occur in the photovoltaic material and its interfaces2. The expression “in-situ characterization” can be defined as a time-resolved measurement that monitors a change without removing the sample from the conditions producing the change. In PSC this would imply a characterization method that can be carried out with continuous illumination, applied temperature or applied bias in a whole or part of the device. This poster aims to present an overview of selected in-situ characterization techniques that we have specifically adapted and implemented for better PSC characterization and data collection. These methods include X-ray diffraction with applied electrical bias, UV-visible light, temperature, humidity and atmosphere, impedance spectroscopy, steady state and time-resolved photoluminescence with applied bias and Raman spectroscopy with applied bias. With this comprehensive description of techniques we aim to encourage researchers to expand their characterization specifically focusing on stability. References: 1. Khenkin, M. V., et al., Nature Energy (2020) 5 (1), 35 2. Lira-Cantú, M., Nature Energy (2017) 2 (7), 17115

Resume : Perovskite solar cells (PSCs) have received significant recognition not only because of their excellent photovoltaic properties but also due to their facile fabrication and low-cost processing. Significant efforts towards improving the efficiency and stability of PSCs have been made in the past few years and to date more than 26% of efficiency has been achieved.1 Although there are several reports showing improved efficiencies, most of them failed when it comes to stability. Shallow defects in perovskites is a major contribution to the stability loss and this loss can be minimized by passivating these defects through surface modifications.2 Chemical modifications on material surface is a favourable approach to improve the stability of materials by controlling the surface properties by bringing novel chemical, electronic and optical properties.3 Two-dimensional (2D) materials are excellent candidates for potential applications including photovoltaics owing to their high conductivity, hydrophilicity, flexibility, and surface modifications.4 MXene-based 2D materials are highly conductive, hydrophilic and have highly charged surfaces making them promising for future applications in electronics, photodetectors, light emitting, spintronic and memory devices.5 Though there are huge studies going on MXenes, their exploration in PSCs is scarce. MXenes show metallic conductivity that can be utilized as electrodes in dye-sensitized solar cells (DSSCs), electron transport layers (ETLs) in PSCs and as additives on perovskite layers.6 They are thermodynamically stable under ambient atmosphere at nanoscale dimensions. Surface functionalization of MXenes is an effective way to tune the work function and it also enables the transition from metallic to semiconducting state. Moreover, MXene layer number and spacing can remarkably affect their properties in improving the efficiency and stability of PSCs. In this work, the effect of Ti3C2Tx MXene modified with organic additives on a multication perovskite absorber has been studied. 3-phosphopropionic acid (H3pp) and octylphosphonic acid (OPA) modified Ti3C2Tx MXenes (Ti3C2Tx–H3pp and Ti3C2Tx–OPA) have been used to fabricate the cells. PSCs with H3pp and OPA modified MXenes showed outstanding photovoltaic performance, with an open-circuit voltage (Voc) of ~1.13 V, a fill factor (FF) of 79.56 %, and a PCE of more than 20 % while the reference device had a PCE of 19.63 %. Furthermore, a better Voc indicates that the modified MXenes effectively passivates the shallow defects towards improving the PSC stability. Stability analyses of these PSCs under ISOS-D1 protocol showed minimal loss of the initial efficiency after 1800 h under 1 sun, whereas the reference device (without MXenes and organic additives) showed >23 % loss under the same conditions.7 References [1]. Agresti, A. et al. Nat. Mater. 18, 1228–1234 (2019). [2]. Xie, H. et al. Joule 5, 1246–1266 (2021). [3]. Ji, J., Zhao, L., Shen, Y., Liu, S. & Zhang, Y. FlatChem 17, 1–6 (2019). [4]. Bati, A. S. R. et al. Small 17, 1–9 (2021). [5]. Yang, L. et al. Adv. Funct. Mater. 29, 1–8 (2019). [6]. Yang, L. et al. J. Mater. Chem. A 9, 5016–5025 (2021). [7]. Khenkin, M. V. et al. Nat. Energy 5, 35–49 (2020).

Resume : Flexible perovskite solar cells have achieved high efficiencies above 20% 1, but still their stability and durability are of major concerns of commercialization for printable electronics 2. Recently, application of two dimensional materials have attracted researchers due to their charge transport in vertical geometry, band alignment with perovskites and also their ease of solution processing preparation. For example, recently Karimipour et al. 2 have shown the application of thin MoS2 nanosheets can improve bending durability of flexible lead-based perovskite solar cells using a ligand bridging simultaneously. Novel Mxene (Ti3C2-Tx) nanosheets have shown also to be promising as HTL intermediator in the rigid perovskite solar cells 3. One of the major concern about their application, is that they are in metallic phase and their band alignment in device fabrication should be taken into account. On the other hand, additive engineering has been a pathway to passivate the interface defects and shallow traps for achieving more stable perovskite solar cells 4. Combining the aforementioned techniques, in this work we are going to present a highly stable and mechanically durable flexible solar cell by sandwiching perovskite layer between functionalized Mxene nanosheets with significant charge transport properties, thermal stability and high tolerance strain/stress properties. Our initial results show that Mxene functionalization can passivate interface traps and yield higher stability for high efficiency perovskite solar cells. References 1. Chung, J. et al. Record-efficiency flexible perovskite solar cell and module enabled by a porous-planar structure as an electron transport layer. Energy Environ. Sci. 13, 4854–4861 (2020). 2. Karimipour, M., Khazraei, S., Kim, B. J., Boschloo, G. & Johansson, E. M. J. Efficient and bending durable flexible perovskite solar cells via interface modification using a combination of thin MoS2 nanosheets and molecules binding to the perovskite. Nano Energy 95, 107044 (2022). 3. Chen, T. et al. Accelerating hole extraction by inserting 2D Ti3C2-MXene interlayer to all inorganic perovskite solar cells with long-term stability. J. Mater. Chem. A 7, 20597–20603 (2019). 4. Xie, H. et al. Decoupling the effects of defects on efficiency and stability through phosphonates in stable halide perovskite solar cells. Joule (2021).

Resume : Despite the high power conversion efficiencies above 25% achieved within the last decade of research on lead-halide perovskite materials, the photovoltaic industry is yet to witness significant commercial success with perovskite solar cells (PSCs) due to the poor lifetime and stability of these devices. Although an in-depth understanding of the origin of the intrinsic and extrinsic degradation mechanisms is being rapidly acquired for these materials, the achievements targeting device stability are still lagging far behind the progress made in the power conversion efficiency[1-3]. While addressing intrinsic degradation by developing new stable perovskite material and optimizing the device architecture, a robust encapsulation with high barrier performance materials is an indispensable step to combat the poor lifetime/stability problems encountered in PSC devices when exposed to harsh outdoor ageing stressors[4,5]. Here, we present different encapsulation strategies that we have applied to PSCs for outdoor testing and analyse the effects of different types of epoxies on perovskite materials. As a part of the European project ProperPhotoMile (Solar-era.net Cofund-2) this data will feed the big data analysis for automated machine learning algorithms aimed at unravelling the influence of different factors on PSC stability and prediction of device lifetimes. References [1] Kim, H.-S., et al., Sci. Rep., 2012, 2, 591 [2] NREL Best Research-Cell Efficiency Chart; https://www.nrel.gov/pv/cell-efficiency.html [3] Guo, R., Han, D., Chen, W. et al., Nat Energy 6, 977–986 (2021) [4] F. Corsini and G. Griffini, J. Phys. Energy 2 (2020) 031002 [5] Ma, S., et al., Energy Environ. Sci., 2022, 15, 13-55

Resume : The growing environmental crisis has led to explore and forced the human being to innovate new technologies for the generation of energy obtained from renewable and sustainable energy sources. For this, photovoltaic solar energy is very attractive since it is clean and inexhaustible, mainly perovskite solar cells promise a breakthrough due to their rapid growth in a few years. Nowadays, the bottleneck of these devices lies in the lack of long-term stability, oxides have played a fundamental role in the incipient development of photovoltaic technology. The substitution of classical semiconductor oxides applied in PSC as transport layers (such as TiO2 or SnO2), by ferroelectric oxides, especially Lead Zirconate Titanate (PZT) and Bismuth Ferrite (BFO), can improve photovoltaic performance. Ferroelectric solar cells exhibit switchable photocurrent and photovoltage, and band gap open circuit voltages, due to these magnificent properties ferroelectric oxides have become an emerging field in applied solar cell research. In this project, we have demonstrated that the build-in electric field can be enhanced by ferroelectric oxides causing more charges to separate in solar cells, significantly improving the PCE of the device. We have prepared PSCs applying ferroelectric oxides as ETL. The oxide BFO was synthesized by sol gel solution and applied by spin coating on top of the FTO electrode. The BFO thin film was applied as a dense thin layer and a coating of the halide perovskite was deposited on top in a perovskite oxide/halide perovskite heterojunction. Conductivity measurements performed to the BFO thin film confirmed the change in conductivity of the BFO in agreement with the improvement of PCE of the solar cell. This indicates that the initial ferroelectric oxide modifies its transport properties from insulator to conductor in detrimental to its ferroelectric properties. We have also observed a dependency of the halide perovskite grain size on the final photovoltaic properties of the devices. Finally, we carried out stability analysis of the solar cells. Our results demonstrate that the devices show good photovoltaic properties even under conditions of UV light irradiation which confirms that the BFO provides enhanced stability to the solar cells. But the most important finding was that the short circuit current increases with the amplitude of the poling voltage while the open circuit voltage value remains the same, around 0.6 V. This could be explained as a more efficient collection of the charges generated under illumination in the absorbing film, due to the polarization that is present in the ferroelectric layer. References [1]. Lira-Cantú, M., et al., Nature Energy 2017, 2 (7), 17115. [2]. A. Pérez-Tomas, H. Xie, Z Wang et al. Sustainable Energy & Fuels 2019, 3 (2), 382-389. [3] G. Che, J. Chen, W. Pei et al., Materials Research Bulletin 2019, 39-49. [4]. L. You, F. Zheng, L. Fang et al. Science Advances 2018, 4 (7). [5]. A. Lipatov, A. Fursina, T. Vo et al. Advanced Electronic Materials 201, 3 (7), 1700020

Resume : This study is undertaken to model battery and analyze its performance for different electric vehicle segments. An accurate and reliable battery model is a major requirement for designing an energy efficient charging system. Whether the battery is used for electric transportation or any other consumer application, every design requires consideration of complex characteristics of battery. Battery being considered as a black box, any model built should effectively reflect the real time non-linear characteristics of a battery including memory effect, polarisation effect, capacity fading, double layer effect, temperature, and current dependency on transient responses. One of the critical barriers in an electric vehicle application is accuracy in range prediction. The accurate equivalent model of a battery would greatly help in a better control of battery chargers, efficient optimisation of battery application, accurate range prediction, accurate development of battery management systems and reduce the design cycle time requirement. To predict the battery characteristics accurately, various modelling approaches could be adopted. Mathematical modelling, electrochemical modelling, equivalent circuit modelling, data driven modelling are some of the approaches. Electrochemical models have highest accuracy as they consider the microscopic behaviour of the battery, hence have highest complexity leading to high effort in parameter identification. Empirical models are fast, but they do not consider all the battery characteristics. Data driven models work based on the accuracy rate at which large data sets are computed. Hence the computational time associated with this model is higher. Equivalent Circuit Model (ECM) holds higher accuracy and lesser computational power compared to rest of the modelling approaches. This paper presents the Equivalent Circuit Model to predict the practical battery performances. Modified Thevenin model is simulated in MATLAB environment, and the model reflects the practical dynamic characteristics of battery. The major components of the circuit model are the open circuit voltage as a function of State of Charge (SoC), internal resistance representing the self-discharge and a pair of R-C parallel branch reflecting the polarisation and double layer effect. The temperature effect on the battery is considered for modelling. The SoC estimation is addressed by using the Extended Kalman filter estimation technique and modelling is done by using practical test results. The model developed is validated by simulating it with different practical vehicle charging systems. The discharge characteristics of the model with the Modified Indian Driving Cycle (MIDC) is also addressed. The analysis of error in predicted battery parameters by the model from practical battery performace is presented. The battery performance when used in different EV models is simulated by considering the applicable drive cycles. References: [1]. Jinhao Meng, Guangzhao Luo, Mattia Ricco, Maciej Swierczynski, Daniel-IoanStroe, and Remus Teodorescu. Overview of lithium-ion battery modeling meth-ods for state-of-charge estimation in electrical vehicles.Applied sciences, 8(5):659,2018. [2]. Sulzer, V., Marquis, S. G., Timms, R., Robinson, M., & Chapman, S. J. (2021). Python battery mathematical modelling (PyBaMM). Journal of Open Research Software, 9(1). [3]. Tamilselvi, S., Gunasundari, S., Karuppiah, N., Razak RK, A., Madhusudan, S., Nagarajan, V. M., ... & Afzal, A. (2021). A review on battery modelling techniques. Sustainability, 13(18), 10042. [4]. Vergori, E., Mocera, F., & Somà, A. (2018). Battery modelling and simulation using a programmable testing equipment. Computers, 7(2), 20. [5]. Tian, J., Xiong, R., Shen, W., & Sun, F. (2020). Fractional order battery modelling methodologies for electric vehicle applications: Recent advances and perspectives. Science China Technological Sciences, 63(11), 2211-2230. [6]. Dunn, B., Kamath, H., & Tarascon, J. M. (2011). Electrical energy storage for the grid: a battery of choices. Science, 334(6058), 928-935. [7]. Hanifah, R. A., Toha, S. F., & Ahmad, S. (2015). Electric vehicle battery modelling and performance comparison in relation to range anxiety. Procedia Computer Science, 76, 250-256.

Resume : Lithium -ion Batteries (LiB) are one among the extensively used electrochemical storage units in Electric vehicles (EVs) as well as in consumer electronics applications. Transportation is shifting towards an era of electrification and the automaker’s electric commitments are increasing at a rapid pace. Once the EV batteries reach their end-of-life, they can no longer be used as traction batteries. EV batteries are continuously subjected to variable charge and discharge rates, extreme operating temperatures, and partial cycles in their lifetime. This results in substantial reduction in their capacity within few years of their primary vehicle application. At this stage, even if the battery does not satisfy the existing performance standards for vehicle usage, it may retain 80% of its capacity making it suitable for secondary life applications. These spent EV batteries can either be reconditioned, refurbished, or may undergo repurposing according to the usable capacity left after the primary usage. Value proposition, consumer segmentation, channels of reuse, revenue flows and key implementation partners are some of the parameters that would assist in decision making for the appropriate methodology for reuse. The primary step carried out for reuse determination is the root cause analysis for determining the degree of damage, degradation, and ageing caused to the spent batteries. After these steps, a post diagnosis can be done to predict the State of Health (SoH) and Remaining Used Life (RUL), which in turn helps in classification of these End of Life (EoL) batteries. This paper presents an analysis of different second life usage of Electric Vehicle batteries including usage in an electric vehicle fast-charging station, as storage element in renewable energy application, as excitation unit in generating stations, in transmission deferral or other consumer applications. Post diagnosis methodology for estimating the SoH and RUL of the batteries is also presented. The model for predicting these factors is run on MATLAB environment and based on the results, predicted value of temperature variation, SoH estimated value, and the voltage variation of testing, a classification of appropriate secondary life application is addressed. A review of international standards available for battery reuse is also included. Additionally, improvements required in the Battery Management System when shifted from primary vehicle application to any secondary life usage is also analyzed. References [1]. Casals, L. C., García, B. A., & Canal, C. (2019). Second life batteries lifespan: Rest of useful life and environmental analysis. Journal of environmental management, 232, 354-363. [2]. Ahmadi, L., Young, S. B., Fowler, M., Fraser, R. A., & Achachlouei, M. A. (2017). A cascaded life cycle: reuse of electric vehicle lithium-ion battery packs in energy storage systems. The International Journal of Life Cycle Assessment, 22(1), 111-124. [3]. Wood, E., Alexander, M., & Bradley, T. H. (2011). Investigation of battery end-of-life conditions for plug-in hybrid electric vehicles. Journal of Power Sources, 196(11), 5147-5154. [4]. Martinez-Laserna, E., Sarasketa-Zabala, E., Stroe, D. I., Swierczynski, M., Warnecke, A., Timmermans, J. M., ... & Rodriguez, P. (2016, September). Evaluation of lithium-ion battery second life performance and degradation. In 2016 IEEE Energy Conversion Congress and Exposition (ECCE) (pp. 1-7). IEEE. [5]. Dunn, B., Kamath, H., & Tarascon, J. M. (2011). Electrical energy storage for the grid: a battery of choices. Science, 334(6058), 928-935.

Resume : Organic-inorganic halide-based perovskites (OIHPs) have displayed tremendous promise as next-generation energy efficient materials in a plethora of applications. Their versatility to cater different device physics lies in their phenomenal features such as absorption across the IR to UV spectral range, easy and low-cost processing, photogeneration of free carriers, long diffusion length of charge carries, low trap density, tunability of dimensionality through chemical composition and synthesis routes.1 The ‘natural quantum well’ structures observed in the low dimensional OHIPs, is found to be well suited for devices like LEDs, LASERs, non-linear optical switches and memristors. Low dimensional halide perovskites exhibit the capability for enhancing device performance in memory storage and as futuristic material for internet of things (IoT). 2 The present challenges faced in commercializing any device with OHIPs can be majorly summed as; toxicity (lead-based perovskites are most popular) and instability (moisture, light exposure, temperature). Herein, we have designed two, robust low dimensional halide perovskites using a chiral organic cation. The chirality of the organic cation offers a very simple yet structured degree of freedom for resistive switching the withing the system. Both the perovskites i.e., [CA]2PbBr4 (1) and [CA]2BiBr6 (2) are single crystals that are grown by solution processed vapor diffusion growth mechanism. The single crystal XRD analysis reveals an 2D layered structure for the 1 and a 1D ribbon structure for 2. The thin films of these materials were done using hot casting route yielding smooth, uniform and pin-hole free surfaces. Resistive switching behavior was studied for these films and it Bi-based system 2, was seen to better perform as compared to 1. The operating range of 0-2V is seen as the most efficient, thus providing us with a low voltage lead-free memristor. This novel material is developed with an idea to divulge into next-generation neuromorphic memory devices using OHIPs and provides a comparison for Pb and Pb free based systems. It also emphasis, the need to explore the role of cations in OHIPs to design robust materials for these energy applications. References: 1. Journal of Physics D: Applied Physics 54 (13), 133002, 2021 2. J Phys Chem Lett. 12(37), 8999, 2021