ECS Meeting Abstracts最新文献

{"title":"Influence of A-site Deficiency and Ni/Co Ratio in B-site on Electrochemical Performance of (La_0.25Sr_0,25Ca_0.45)_yTi_0.95Ni_0.05-xCo_xO_3- _d Anode","authors":"Indrek Kivi, Priit Moeller, Jaan Aruväli, Gunnar Nurk","doi":"10.1149/ma2023-015480mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-015480mtgabs","url":null,"abstract":"La 0.25 Sr 0.25 Ca 0.45 TiO 3 - d (LSCT) is a perovskite (ABO 3 ) type mixed ionic-electronic conductive (MIEC) oxide and has been proposed as an electrode material for high temperature fuel cell [1]. This material owing high conductivity, robustness in hydrocarbon fuels and significant amount of attention has been paid to improve the electrochemical activity [1, 2]. Doping of B-site with some d-metal cation (Ni, Co, Mn, V, Mo) has been demonstrated to improve the catalytic activity. One of the advantages of the MIEC conducting scaffold based electrodes is that the catalyst phase on the electrode surface can be kept to a minimum, usually less than 5 wt%, which minimizes any risks of physical damage during redox cycling [2]. In this work, Ni/Co ratio and deficiency of A-site, of (La 0.25 Sr 0.25 Ca 0.45 ) x Ti 0.95 Ni 0.05-y Co y O 3 - d were varied. Electrical as well as electrochemical performance and chemical composition of LSCTNC surface was monitored. The electrochemical measurements of symmetric cells during 100 h tests show that small stochiometric changes in A-site significantly influence the activity and initial degradation rate of the electrode. The chemical and structural changes of the material surface have a key role on the electrochemical performance of the electrode [3]. The electrode materials were analysed using XRD, TOF SIMS and electrochemical methods. XRD and TOF SIMS results for studied electrode powders showed significant dependence of the lattice parameters and electrode surface composition on the perovskite elemental composition. The results from impedance spectroscopy (measured at temperatures from 973 to 1123 K in H 2 environment, at OCV) demonstrate a significant influence of the A-site deficiency and B-site composition on the electrochemical properties of studied electrodes. Robert Price, Mark Cassidy, Jan G. Grolig, Gino Longo, Ueli Weissen, Andreas Mai, John T. S. Irvine, Advanced Energy Materials, 11, 1 (2021). Paul A. Connor, Xiangling Yue, Cristian D. Savaniu, Robert Price, Georgios Triantafyllou, Mark Cassidy, Gwilherm Kerherve, David J. Payne, Robert C. Maher, Lesley F. Cohen, Rumen I. Tomov, Bartek A. Glowacki, Ramachandran Vasant Kumar, John T. S. Irvine, Advanced Energy Materials, 8, 1 (2018). Ove Korjus, Priit Möller, Kuno Kooser, Tanel Käämbre, Olga Volobujeva, Jaak Nerut, Sander Kotkas, Enn Lust, Gunnar Nurk, Journal of Power Sources, 494, 1 (2021).","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Versatile and Reversible Multi-Stack Solid Oxide Cell System Towards Operation Strategies Optimization","authors":"Geraud Cubizolles, Simon Alamome, Félix Bosio, Brigitte Gonzalez, Christian Tantolin, Lucas Champelovier, Sebastien Fantin, Jerome Aicart","doi":"10.1149/ma2023-0154258mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-0154258mtgabs","url":null,"abstract":"High Temperature Electrolysis based on Solid Oxide Cell technology is rapidly entering an industrialization phase, driven by promises of high efficiencies compared to the more market-ready solutions. To decrease the CAPEX and footprint related to module-based scale-up strategies, multiple stacks are typically assembled within the same thermal enclosure. As such, thermal phenomena become much more prominent in determining stack behavior compared to single stack test benches, and appropriate control strategies have to be developed. In this context, CEA LITEN has developed a new investigation tool (MURPHY) devoted to the operation of several Solid Oxide stacks within the same thermal enclosure. MURPHY enables stack operation in both the steam electrolysis (SOE) and the fuel cell (SOFC-H 2 ) modes. For the later, CH 4 , natural gas or NH 3 can be used as fuel, while additional gases are being considered. The one module system incorporates a compact Balance of Plant (BOP) located closely to the thermal enclosure. Its main functions are (i) to provide inlet process air by centrifugal blower towards higher efficiency, (ii) target high level of overall thermal integration and performances, (iii) actively preheat inlet gases independently of overall furnace temperature, (iv) recycle hot/cold fuel exhaust, and (v) control pressure levels distribution through multiple back-pressure valves. Overall, a high level of instrumentation was deployed to support modeling development and estimate accurate process efficiencies. MURPHY is currently compatible with four stacks of CEA standard base design [1]. Each comprising 25 cathode-supported cells each of 100 cm² active area, the corresponding maximum power range of the module is -16/4 kW DC [2], [3]. Nevertheless, the Hot Box has some capacity to adapt to different stack geometries and partner’s need. Finally, the MURPHY system is connected to the Multistack platform [4] for supply and venting of gases produced. This report details system architecture down to component level. It also puts forward preliminary experimental results related to stack operation in an environment controlled by thermal phenomena. Performance and efficiency curves obtained under parametric variations of operating conditions (Temperature, flowrates) are reported for both SOE and SOFC-H 2 modes. A special attention is given to heat performance of the overall system and its components. In this view, flow parameters (composition, temperature, pressure) at several locations over the reactant circuitries are provided. [1] G. Cubizolles, J. Mougin, S. Di Iorio, P. Hanoux, and S. Pylypko, “Stack Optimization and Testing for its Integration in a rSOC-Based Renewable Energy Storage System,” ECS Trans. , vol. 103, no. 1, pp. 351–361, Jul. 2021, doi: 10.1149/10301.0351ecst. [2] J. Aicart, S. Di Iorio, M. Petitjean, P. Giroud, G. Palcoux, and J. Mougin, “Transition Cycles during Operation of a Reversible Solid Oxide Electrolyzer/Fuel Cell (rSOC) System,","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":"07 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"UV-Controlled Nitrene Crosslinking in Poly(phenylene oxide) Anion Exchange Membranes","authors":"Auston L. Clemens, Maira Raquel Ceron, Magi Mettry Yassa, Thomas Ferron, Adam Barnett, Joshua Aaron Hammons, Buddhinie Jayathilake, Valeria Molinero, John Joseph Karnes, James Spencer Oakdale","doi":"10.1149/ma2023-01402882mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01402882mtgabs","url":null,"abstract":"Anion exchange membranes (AEMs) promise significant capital cost saving associated with enabling use of Pt-group-free electrodes and components in alkaline fuel cells and electrolyzer devices. However, AEMs often lack the chemical and mechanical stability required for widespread commercial adoption. Crosslinking has proven to be an effective method to permit increased ion exchange capacity (IEC) while preventing exponential water uptake and retaining both conductivity and mechanical strength. In this work, we leverage molecular dynamics simulations to explore crosslinking methodologies in silico. We present a reproducible and quantitative UV-based nitrene chemistry that utilizes a mobile crosslinker that is straightforward to synthesize and implement. This crosslinking strategy significantly mitigates excess water uptake and improves alkaline stability without sacrificing IEC during the cure process. Additionally, we characterize electrochemically fielded AEMs by small angle X-ray scattering, mechanical strength testing, and other post-mortem analyses. The operational lifetime of crosslinked AEMs prepared in this work is 5 times greater than corresponding untreated AEMs. This work is performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 within the LDRD program 21-ERD-013. LLNL-ABS-848147.","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perovskite-Based Materials As Alternative Fuel Electrodes for Solid Oxide Electrolysis Cells (SOECs)","authors":"Franziska Elisabeth Winterhalder, Yousef Alizad Farzin, Olivier Guillon, Andre Weber, Norbert H. Menzler","doi":"10.1149/ma2023-0154169mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-0154169mtgabs","url":null,"abstract":"Enhancing the lifetime of SOECs is a challenge to overcome regarding their commercialization. A major impact on the lifetime of a cell during electrolysis operation, particularly under thermoneutral potential and high current densities, is the degradation of the currently used electrode materials, mainly the Ni-based fuel electrode. Among other things, nickel migration, as well as agglomeration, is leading to a significant performance loss after a certain operating time. Hence, preventing degradation mechanisms of the fuel electrode during operation is a necessity to be tackled for using it commercially. Therefore the development of alternative materials which combine sufficient performance with the lowest possible degradation rate is needed. Perovskite-based materials have been investigated in the last years as all-ceramic possible substitutes. In this work, four perovskites (i.e., strontium-iron-niobate double perovskite (SFN), a strontium-iron-titanate material (STF), a lanthanum-strontium-titanate (LST) and a lanthanum-strontium-iron-manganese (LSFM)) were examined as alternative electrode materials. The aim is to substitute the active fuel electrode, at the moment commonly consisting of Ni cermets, with a perovskite-based electrode while at the same time using state-of-the-art materials for the remaining cell components. The first task here was to look at the chemical stability between the new electrode material and the electrolyte under the standard conditions used to manufacture fuel electrode-supported SOECs. Therefore, the compatibility between these perovskites with a yttria-stabilized-zirconia (8YSZ) electrolyte and how nickel inside the fuel electrode affected the chemical stability during sintering in air at 1400 °C for 5 h was investigated. At this point, SFN double perovskite shows the lowest interaction between the electrode and electrolyte after thermal treatment. A thorough evaluation of all preliminary tests (including compatibility, stability in reducing atmospheres and redox stability tests) indicates that SFN shows so far the best results of the four materials in terms of application as fuel electrode material, followed directly by STF. Thus SFN and STF were chosen to be evaluated in single cell tests. The tests of pure SFN and STF electrodes are carried out with electrolyte-supported single cells exhibiting an LSCF air electrode and symmetrical cells, respectively. CV-characteristics and impedance spectra are measured at varied operating conditions. Impedance spectra are evaluated by the distribution of relaxation times (DRT). These examinations are carried out to give an insight into the electrochemical properties of pure perovskite-based fuel electrodes in order to obtain a base for further optimization.","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Materials Graph Networks Assisting the Discovery of New Solid-State Electrolyte Materials","authors":"Salatan Duangdangchote, Oleksandr Voznyy","doi":"10.1149/ma2023-01452471mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01452471mtgabs","url":null,"abstract":"Finding novel solid-state electrolyte materials with specific desired properties is one of the main challenges of first principles-based modelling due to its high computational cost. Recently, machine learning (ML) has been used exclusively in the materials discovery field due to its remarkable capabilities to process large amounts of data and extract useful information insights. The implementation of ML into atomic-scale materials modeling can accelerated materials sampling with first principles accuracy, this should provide a short workflow and highly reduce the computational cost. In this work, we facilitate the ML model that can effectively screen for targeted properties from the entire chemical database possibility, including those materials that have never been examined. Currently, we are developing a materials graph networks framework for representing periodic crystal systems with the capability to learn atomistic chemical insights, especially for the discovery of new solid-state electrolyte materials. In this talk, we will discuss the basic theory and our recent work towards the development of ML model that can extensively discover and explore materials. We will highlight the computational-guided evolution approaches and screening high-performance Li conductor materials. Finally, we will end on discussing the future of ML-assisted materials discovery to the future of all-solid-state lithium batteries.","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"(Invited) Bioelectrochemical Strategies for C-H Activation","authors":"Shelley D. Minteer","doi":"10.1149/ma2023-01442420mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01442420mtgabs","url":null,"abstract":"Petroleum hydrocarbons are currently our major energy source and an important feedstock for the chemical industry. Beyond combustion, conversion of chemically inert hydrocarbons to more valuable chemicals is of considerable interest. However, two challenges hinder this conversion. One is the regioselective activation of inert carbon–hydrogen (C–H) bonds. The other is designing a pathway to realize this complicated conversion. This paper will discuss the use of alkane monoxygenases in bioelectrochemical systems for C-H activation, as well as enzyme cascades and hybrid catalytic cascades for the conversion of inert alkanes to complex organic molecules like imines with selectivity far beyond traditional homogeneous and heterogeneous catalysts.","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stable Organic Radical for Enhancing Metal-Monolayer-Semiconductor Junctions Performance","authors":"Bruno Fabre, Jesus Alejandro De Sousa, Raphael Pfattner, Concepcio Rovira, Marta Mas-Torrent, Nuria Crivillers","doi":"10.1149/ma2023-01442408mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01442408mtgabs","url":null,"abstract":"Among the large amount of families of molecules investigated in molecular junctions (MJs), stable free organic radicals have gained an increasing attention over the last years. 1 Thanks to their open-shell electronic configuration, these molecules are paramagnetic, redox and optically active, which make them appealing species for a variety of applications. 2 Chlorinated trityl radicals, and in particular the perchlorotriphenylmethyl radicals have shown to be highly stable as active molecular units in MJs. 3 Such functional molecules have been recently covalently bound to photoactive, hydrogen-terminated silicon surfaces and the so modified surfaces have been demonstrated to function as light-triggered capacitance switches with good stability. 4 Herein, the charge transport of these systems, employing the open- and closed-shell molecules ( Rad-PTM and α H-PTM , Figure 1a), is investigated as solid-state Metal/monolayer/Semiconductor (MmS) junctions using an eutectic Gallium-Indium liquid metal as the top electrode. A characteristic diode behavior is observed which is tuned by the electronic characteristics of the organic molecule. Our results clearly indicate that the presence of the SOMO-SUMO molecular orbitals impacts on the device performance. The junction incorporating the radical shows an almost two orders of magnitude higher rectification ratio ( R = 10 4.04 ) in comparison with the non-radical one ( R = 10 2.30 ) at ± 1 V bias. Interestingly, the high stability of the fabricated MmS permits to interrogate the system under irradiation, evidencing that at the wavelength where the photon energy is close to the band gap of the radical, there is a clear enhancement of the photoresponse. 5 (1) Ratera, I.; Vidal-Gancedo, J.; Maspoch, D.; Bromley, S. T.; Crivillers, N.; Mas-Torrent, M. J. Mater. Chem. C 2021 , 9 , 10610–10623. (2) Mas-Torrent, M.; Crivillers, N.; Mugnaini, V.; Ratera, I.; Rovira, C.; Veciana, J. J. Mater. Chem. 2009 , 19 , 1691–1695. (3) Bejarano, F.; Olavarria-Contreras, I. J.; Droghetti, A.; Rungger, I.; Rudnev, A.; Gutiérrez, D.; Mas-Torrent, M.; Veciana, J.; Van Der Zant, H. S. J.; Rovira, C.; et al. J. Am. Chem. Soc. 2018 , 140 , 1691–1696. (4) De Sousa, J. A.; Bejarano, F.; Gutiérrez, D.; Leroux, Y. R.; Nowik-Boltyk, E. M.; Junghoefer, T.; Giangrisostomi, E.; Ovsyannikov, R.; Casu, M. B.; Veciana, J.; et al. Chem. Sci. 2020 , 11 , 516–524. (5) De Sousa, J. A.; Pfattner, R.; Gutiérrez, D.; Bromley, S. T.; Veciana, J.; Rovira, C.; Mas-Torrent, M.; Fabre, B.; Crivillers, N. ACS Appl. Mater. Interf ., submitted. Figure 1","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"(Keynote) Electrochemical Proton-Coupled Electron Transfer Theory","authors":"Sharon Hammes-Schiffer","doi":"10.1149/ma2023-01452453mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01452453mtgabs","url":null,"abstract":"Proton-coupled electron transfer (PCET) plays a vital role in a wide range of electrochemical processes. This talk will describe theoretical and computational methods that have been developed to study electrochemical PCET and a variety of applications to molecular and heterogeneous electrocatalysis. My group has formulated a general PCET theory that includes the quantum mechanical effects of the electrons and transferring protons, as well as the motions of the donor-acceptor modes and solvent or protein environment. This PCET theory enables the calculation of rate constants and kinetic isotope effects for comparison to experiment. Our extension of this theory to electrochemical PCET incorporates the electronic structure of the electrode and the interfacial electric fields arising from the electrical double layer. Theoretical formulations for both homogeneous and heterogeneous electrochemical PCET provide analytical expressions for the rate constants and current densities as functions of applied potential. This theory has been applied to proton discharge on metal electrodes, as well as PCET at metal oxides and graphite-conjugated catalysts. These applications highlight the importance of using a theory that quantizes the transferring proton and includes the effects of hydrogen tunneling and excited electron-proton vibronic states. The insights from these theoretical studies are useful for the design of electrocatalytic systems to control the movement and coupling of electrons and protons for energy conversion processes. References Venkataraman, A. V. Soudackov, and S. Hammes-Schiffer, Theoretical formulation of nonadiabatic electrochemical proton-coupled electron transfer at metal-solution interfaces, J. Phys. Chem. C 112 , 12386-12397 (2008). K. Goldsmith, Y. C. Lam, A V. Soudackov, and S. Hammes-Schiffer, Proton discharge on a gold electrode from triethylammonium in acetonitrile: Theoretical modeling of potential-dependent kinetic isotope effects, J. Am. Chem. Soc. 141 , 1084-1090 (2019). C. Lam, A. V. Soudackov, and S. Hammes-Schiffer, Kinetics of proton discharge on metal electrodes: Effects of vibrational nonadiabaticity and solvent dynamics, J. Phys. Chem. Lett. 10 , 5312-5217 (2019). E. Warburton, P. Hutchison, M. N. Jackson, M. L. Pegis, Y. Surendranath, and S. Hammes-Schiffer, “Interfacial field-driven proton-coupled electron transfer at graphite-conjugated organic acids,” J. Am. Chem. Soc. 142 , 20855-20864 (2020). E. Warburton, A. V. Soudackov, and S. Hammes-Schiffer, Theoretical modeling of electrochemical proton-coupled electron transfer, Chem. Rev. 122 , 10599-10650 (2022).","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":"127 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"(Digital Presentation) Structure-Activity Relationship of M-N-C Electrocatalysts Synthesized Using a General Solution-Phase Coordination Approach","authors":"Mengxue Huang, Ruimin Ding, Lifang Chen, Jingchao Chen, Chaoqi Han, Wenwen Shi, Jie Yang, Shanshan Liu, Xi Yin","doi":"10.1149/ma2023-01382294mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01382294mtgabs","url":null,"abstract":"Metal- and nitrogen-doped carbon (M-N-C) catalysts have great potential in heterogeneous catalysis. They are used to catalyze various crucial electrochemical reactions, such as the oxygen reduction reaction (ORR), the hydrogen evolution reaction (HER), the oxygen evolution reaction (OER), and the CO 2 reduction reaction (CO 2 RR). 1-4 The nitrogen-coordinated metal sites (MN x ) have been considered the main active sites in these M-N-C catalysts. However, the synthesis of MN x moieties often undergoes a high-temperature heat-treatment step, resulting in low site density. On the other side, the coordination environment in the MN x sites is also affected by the metal species which induced the site formation. Therefore, it is challenging to single out the role of central metal in the structure-activity relationships for these MN x sites. In this presentation, we will discuss our recent progress in the development of a solution-phase coordination synthesis approach targeting M-N-C catalysts with high active-site density and well-defined coordination environments. 5, 6 A series of M-N-C catalysts are synthesized via this approach by coordinating electroactive target metal ions with the nitrogen-coordinated metal-vacancy (MVN x ) sites in N-C templated by sacrificial metals. With a combined experimental and computational approach, we explore the role of sacrificial metals, including s -, p -, 3 d -, 4 d -, and f -block metals, in forming various MVN x sites with unique coordination configurations. The structure-activity relationship between the coordination environment and the catalytic activity for ORR, HER, OER, and CO 2 RR is established by comparing the MN x site structures induced by various sacrificial metals. Furthermore, we will present the activity series of metal centers in M-N-C catalysts with the same and well-defined coordination environment for ORR, HER, OER, and CO 2 RR. These results will guide the future development of M-N-C catalysts. Acknowledgments Financial support from the State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences is greatly appreciated. This study is financially supported by the Shanxi Province grant (Grant No. 20210302123011, 202203021212007, and 202103021224442), and Key Research and Development (R&D) Projects of Shanxi Province (202102070301018). References J. Cui, Q. Chen, X. Li and S. Zhang. Recent advances in non-precious metal electrocatalysts for oxygen reduction in acidic media and PEMFCs: an activity, stability and mechanism study. Green Chemistry , 23 , 6898 (2021). H. He, H. H. Wang, J. Liu, X. Liu, W. Li and Y. Wang. Research Progress and Application of Single-Atom Catalysts: A Review. Molecules , 26 , 6501 (2021). U. Martinez, S. Komini Babu, E. F. Holby, H. T. Chung, X. Yin and P. Zelenay. Progress in the Development of Fe-Based PGM-Free Electrocatalysts for the Oxygen Reduction Reaction. Advanced Materials , 31 , 1806545 (2019). Y. Wang, X. Cui, L. Peng, ","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Valorization of Naturally Abundant Low-Value Peat into Highly Active Non-Platinum Group Metal Oxygen Reduction Catalysts","authors":"Patrick Teppor, Rutha Jäger, Jaak Nerut, Miriam Koppel, Jaan Aruväli, Olga Volobujeva, Enn Lust","doi":"10.1149/ma2023-01382287mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01382287mtgabs","url":null,"abstract":"As society continues to adopt an increasingly eco-friendly stance, the efficient usage of natural resources needs to be maximised. For instance, energy obtained from biomass covers roughly a tenth of the global demand. This biomass can instead be used as a carbon source to produce value-added materials such as tnon-platinum group metal (NPGM) oxygen reduction catalysts, which are desperately sought after as global demand for fuel cells continues to rise [1,2]. For example, peat is an extremely abundant biomass material in Estonia covering roughly 20% of the country [3]. Herein, the viability of using peat-based catalysts as oxygen reduction catalysts in alkaline media was investigated. The peat sourced from a local peatland was processed and modified with inexpensive iron and nitrogen precursors through the common double-pyrolysis and acid washing synthesis procedure into peat-based NPGM catalysts. Additionally, zinc chloride was used as a pore forming agent. The influence of several principal synthesis parameters, e.g. precursor compound type and amount, on the physical and electrochemical properties of these materials was investigated using various characterization methods. The NPGM catalysts obtained from naturally abundant peat were highly microporous systems due to the inclusion of zinc chloride in the synthesis mixture. High onset (~0.93 V vs RHE) and half-wave potential (~0.83 V vs RHE) values were obtained for most of the materials in activity screening experiments conducted with a rotating disc electrode setup using 0.1 M KOH. However, using an excessive amount of the nitrogen precursor in the synthesis proved to be detrimental to the obtained activity. The high activity of the obtained peat-derived catalysts was further investigated in a rotating ring disc electrode setup where the influence of the studied synthesis parameters on the oxygen reduction reaction selectivity was more evident. Acknowledgments This work was supported by the EU through the European Regional Development Fund under projects TK141 “Advanced materials and high-technology devices for energy recuperation systems” (2014-2020.4.01.15-0011), NAMUR “Nanomaterials - research and applications” (3.2.0304.12-0397), NAMUR+ core facility funded by the Estonian Research Council (TT 13), PRG676 “Development of express analysis methods for micro-mesoporous materials for Estonian peat derived carbon supercapacitors” (01.01.2020–31.12.2024) and PUT1581 (1.01.2017–31.12.2020). References F. Jaouen, D. Jones, N. Coutard, V. Artero, P. Strasser, A. Kucernak, Johns. Matthey Technol Rev. 2018, 62, 231. E4tech, 2022, The Fuel Cell Industry Review 2021 . M. Orru, H. Orru, Est. J. Earth Sci. 2008, 57, 87.","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}