@article {1132, title = {A Computational Framework to Accelerate the Discovery of Perovskites for Solar Thermochemical Hydrogen Production: Identification of Gd Perovskite Oxide Redox Mediators}, journal = {Advanced Functional Materials}, year = {2022}, pages = {2200201}, abstract = {A high-throughput computational framework to identify novel multinary perovskite redox mediators is presented, and this framework is applied to discover the Gd-containing perovskite oxide compositions Gd2BB'O6, GdA'B2O6, and GdA'BB'O6 that split water. The computational scheme uses a sequence of empirical approaches to evaluate the stabilities, electronic properties, and oxygen vacancy thermodynamics of these materials, including contributions to the enthalpies and entropies of reduction, ΔHTR and ΔSTR. This scheme uses the machine-learned descriptor τ to identify compositions that are likely stable as perovskites, the bond valence method to estimate the magnitude and phase of BO6 octahedral tilting and provide accurate initial estimates of perovskite geometries, and density functional theory including magnetic- and defect-sampling to predict STCH-relevant properties. Eighty-three promising STCH candidate perovskite oxides down-selected from 4392 Gd-containing compositions are reported, three of which are referred to experimental collaborators for characterization and exhibit STCH activity. The results demonstrate that the high-throughput computational scheme described herein{\textemdash}which is used to evaluate Gd-containing compositions but can be applied to any multinary perovskite oxide compositional space(s) of interest{\textemdash}accelerates the discovery of novel STCH active redox mediators with reasonable computational expense.}, keywords = {concentrated solar energy, density functional theory, hydrogen, Perovskite, thermochemical water splitting}, doi = {https://doi.org/10.1002/adfm.202200201}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202200201}, author = {Bare, Zachary J. L. and Morelock, Ryan J. and Musgrave, Charles B.} } @article {1140, title = {Formation of 6H-Ba3Ce0.75Mn2.25O9 During Thermochemical Reduction of 12R-Ba4CeMn3O12: Identification of a Polytype in the Ba(Ce,Mn)O3 Family}, journal = {Inorganic Chemistry}, volume = {61}, year = {2022}, month = {4}, keywords = {analytical chemistry, inorganic, layered perovskite, organic, oxide, physical, polytype, STCH, thermochemistry}, doi = {10.1021/acs.inorgchem.2c00282}, author = {Strange, Nicholas A. and Park, James Eujin and Goyal, Anuj and Bell, Robert T. and Trindell, Jamie A. and Sugar, Joshua D. and Stone, Kevin H. and Coker, Eric N. and Lany, Stephan and Shulda, Sarah and Ginley, David S.} } @article {1143, title = {Mechanistic understanding of pH effects on the oxygen evolution reaction}, journal = {Electrochimica Acta}, volume = {405}, year = {2022}, pages = {139810}, abstract = {The oxygen-evolution reaction (OER) is pivotal in many energy-conversion technologies as it is an important counter reaction to others that convert stable chemicals to higher-value products using electrochemistry. The local microenvironment and pH for the anode OER can vary from acidic to neutral to alkaline depending on the system being explored, making definitive mechanistic insights difficult. In this paper, we couple experiments, first-principles calculations based on density functional theory, microkinetics, and transport modeling to explore the entire pH range of the OER. At low current densities, neutral pH values unexpectedly perform better than the acidic and alkaline conditions, and this trend is reversed at higher current densities (> 20~mA cm-2). Using multiscale modeling, this switch is rationalized by a change from a dual-reaction mechanism to a single rate-determining step. The model also shows how the alkaline reaction rates dominate in the middle to high pH range. Furthermore, we explore that the local pH for near-neutral conditions is much different (e.g., 2.4 at the reaction surface vs. 9 in the bulk) than the pH extremes, demonstrating the criticality that transport phenomena plays in kinetic activity.}, keywords = {Electrochemistry, Microkinetics, Oxygen evolution reaction}, issn = {0013-4686}, doi = {https://doi.org/10.1016/j.electacta.2021.139810}, url = {https://www.sciencedirect.com/science/article/pii/S0013468621020934}, author = {Julie C. Fornaciari and Lien-Chun Weng and Shaun M. Alia and Cheng Zhan and Tuan Anh Pham and Alexis T. Bell and Tadashi Ogitsu and Nemanja Danilovic and Adam Z. Weber} } @article {1144, title = {Migration of inclusions in a matrix due to a spatially varying interface energy}, journal = {Scripta Materialia}, volume = {206}, year = {2022}, pages = {114235}, abstract = {An interfacial energy can be a function of a bulk field such as temperature or electric field. We find that in a system with a gradient in temperature or electric potential, the resulting variation in interfacial energy can induce a particle to migrate by either surface or bulk diffusion. For a circular particle under a constant unidirectional gradient in the bulk field, the field dependence of the interfacial energy induces a circular particle to move as a circle at a constant velocity along the direction from higher to lower interfacial energy. A linear stability analysis of this steady state migration suggests that perturbations will damp out as time evolves, and thus under these conditions a migrating circular particle is morphologically stable. Other spatial distributions of interface energy can lead to the distortion of an initially circular shaped particle during migration. A phase field model is developed that captures these distortions and verifies the theoretical results mentioned above.}, keywords = {Bulk diffusion, Interface diffusion, Interface energy depends on a field varying with location, Particle migration}, issn = {1359-6462}, doi = {https://doi.org/10.1016/j.scriptamat.2021.114235}, url = {https://www.sciencedirect.com/science/article/pii/S1359646221005157}, author = {Qian Zhang and Scott Barnett and Peter Voorhees} } @article {1145, title = {Operational Limits of Redox Metal Oxides Performing Thermochemical Water Splitting}, journal = {Energy Technology}, volume = {10}, year = {2022}, pages = {2100222}, abstract = {Solar thermochemical hydrogen production is an attractive technology that stores intermittent solar energy in the form of chemical bonds. Efficient operation requires the identification of a redox-active metal oxide (MOx) material that can achieve high conversion of water to hydrogen at minimal energy input. Water splitting occurs by consecutive reduction and reoxidation reactions of MOx. MOx is reduced to MOx-δ and, in the second step, is reoxidized by water recovering the initial MOx and generate H2. The material must reduce at temperatures achievable in concentrated solar receiver/reactors, while maintaining a thermodynamic driving force to split water. At equilibrium, extent of reduction depends on temperature and oxygen partial pressure, and in this analysis, a set of thermodynamic properties, namely, enthalpy and entropy of oxygen vacancy formation, is sufficient to represent MOx. Herein, a method to easily classify materials based on these thermodynamic properties under any condition of oxygen partial pressure and temperature is presented. This method is based on fundamental thermodynamic principles and is applicable for any redox material with known thermodynamic properties. Despite the simplicity of the method, it is believed that this analysis will support future research in targeting thermodynamic properties of redox-active metal oxides.}, keywords = {Hydrogen production, solar energy, thermochemical cycles, thermodynamic properties, water splitting}, doi = {https://doi.org/10.1002/ente.202100222}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/ente.202100222}, author = {Bayon, Alicia and de la Calle, Alberto and Stechel, Ellen B. and Muhich, Christopher} } @article {1148, title = {Revitalizing interface in protonic ceramic cells by acid etch}, journal = {Nature}, volume = {604}, year = {2022}, month = {04}, pages = {479-485}, keywords = {acid treatment, ceramic fuel-cell, electrolysis, high-temperature annealed electrolyte surface, proton conductivity, Protonic ceramic electrochemical cells}, doi = {10.1038/s41586-022-04457-y}, author = {Bian, Wenjuan and Wu, Wei and Wang, Baoming and Tang, Wei and Zhou, Meng and Jin, Congrui and Ding, Hanping and Fan, Weiwei and Dong, Yanhao and Li, Ju and Ding, Dong} } @article {1149, title = {Spatially resolved performance and degradation in a perfluorinated anion exchange membrane fuel cell}, journal = {Electrochimica Acta}, volume = {406}, year = {2022}, pages = {139812}, abstract = {Anion exchange membrane fuel cells may enable future operation with non-precious metal-based catalysts. These systems have a delicate sensitivity to operating conditions such as humidification levels and the presence of CO2 in the air oxidant stream. We present spatially resolved in-situ performance results that shed light on phenomena that are unique to anion exchange membrane fuel cells. For cell construction, a highly conductive perfluorinated anion exchange polymer was used as the membrane and the material in powder form as the ionomer. Experiments were conducted to investigate the effects of humidification, fuel/oxidant concentration, and carbonation effects on the performance and its distribution in the cell. The results indicated that (i) dry conditions at the cathode have a stronger effect than at the anode on overall cell performance, (ii) performance significantly suffered when humidification was below 90\%, (iii) fuel and oxidant dilution effects lead mass-transport losses and were stronger than flow rate effects, (iv) CO2 in the cathode feed stream creates an equilibration disparity between the inlet and outlet sections and CO2 purging is affected by flooding conditions, and (v) after >500~h of operation, performance deteriorates predominantly at the inlet.}, keywords = {2+1D fuel cell model, Anion Exchange membranes, Cathode dry-out, CO poisoning, Fuel cell durability, Mass transport limitations, Segmented fuel cell}, issn = {0013-4686}, doi = {https://doi.org/10.1016/j.electacta.2021.139812}, url = {https://www.sciencedirect.com/science/article/pii/S0013468621020958}, author = {Ashutosh G. Divekar and Michael R. Gerhardt and Christopher M. Antunes and Luigi Osmieri and Ami C. Yang-Neyerlin and Adam Z. Weber and Bryan S. Pivovar and Guido Bender and Andrew M. Herring} } @article {1133, title = {A Thermogravimetric Temperature-Programmed Thermal Redox Protocol for Rapid Screening of Metal Oxides for Solar Thermochemical Hydrogen Production}, journal = {Frontiers in Energy Research}, volume = {10}, year = {2022}, month = {04}, pages = {856943}, keywords = {concentrated solar, hydrogen lcroduction, Perovskite, screening, thermogravimetry, water splitting}, doi = {10.3389/fenrg.2022.856943}, author = {Sanders, Michael and Bergeson-Keller, Anyka and Coker, Eric and O{\textquoteright}Hayre, Ryan} } @article {1151, title = {A comprehensive modeling method for proton exchange membrane electrolyzer development}, journal = {International Journal of Hydrogen Energy}, volume = {46}, year = {2021}, note = {Special issue on the 2nd International Symposium on Hydrogen Energy and Energy Technologies (HEET 2019)}, pages = {17627-17643}, abstract = {Hydrogen attracts significant interests as an effective energy carrier that can be derived from renewable sources. Hydrogen production using a proton-exchange membrane (PEM) electrolyzer can efficiently convert renewable power via water splitting in wide scales{\textemdash}from large, centralized generation to on-site production. Mathematical models with multiple scales and fidelities facilitate the continuing improvements of PEM electrolyzer development to improve performance, cost, and reliability. The model scopes and methods are presented in this paper, which also introduces a comprehensive PEM electrolysis modeling tool based on computational fluid dynamics (CFD) software, ANSYS/Fluent. The modeling tool incorporates electrochemical model of a PEM electrolysis cell to simulate the performance of coupled thermal-fluid, species transport, and electrochemical processes in a product-scale cell or stack by leveraging the powerful meshing generation and CFD solver of ANSYS/Fluent. The thermal-fluid modeling includes liquid water/gas two-phase flow and simulates a PEM electrolysis cell by using Fluent user-defined functions as add-on modules accounting for PEM-specific species transport and electrochemical processes. The modeling outcomes expediate PEM electrolyzer scaling up from basic material development and laboratory testing.}, keywords = {Electrochemical modeling, Hydrogen production, Low temperature electrolysis water splitting, Proton exchange membrane electrolysis cell}, issn = {0360-3199}, doi = {https://doi.org/10.1016/j.ijhydene.2021.02.170}, url = {https://www.sciencedirect.com/science/article/pii/S0360319921007448}, author = {Zhiwen Ma and Liam Witteman and Jacob A. Wrubel and Guido Bender} } @article {1114, title = {Computationally Accelerated Discovery and Experimental Demonstration of Gd0.5La0.5Co0.5Fe0.5O3 for Solar Thermochemical Hydrogen Production}, journal = {Frontiers in Energy Research}, volume = {9}, year = {2021}, doi = {https://doi.org/10.3389/fenrg.2021.750600}, author = {J. E. Park and Z. J. L. Bare and R. J. Morelock and M. A. Rodriguez and A. Ambrosini and C. B. Musgrave and A. H. McDaniel and E. N. Coker} } @article {1154, title = {Effect of Nanoscale Ce0.8Gd0.2O2-δ Infiltrant and Steam Content on Ni{\textendash}(Y2O3)0.08(ZrO2)0.92 Fuel Electrode Degradation during High-Temperature Electrolysis}, journal = {Nano Letters}, volume = {21}, year = {2021}, note = {PMID: 34606281}, pages = {8363-8369}, keywords = {degredation, duel electrode, infiltration, solid oxide electrolysis cell}, doi = {10.1021/acs.nanolett.1c02937}, url = {https://doi.org/10.1021/acs.nanolett.1c02937}, author = {Park, Beom-Kyeong and Cox, Dalton and Barnett, Scott A.} } @article {1155, title = {Elucidating the Role of Hydroxide Electrolyte on Anion-Exchange-Membrane Water Electrolyzer Performance}, journal = {Journal of The Electrochemical Society}, volume = {168}, year = {2021}, month = {05/2021}, pages = {054522}, abstract = {Many solid-state devices, especially those requiring anion conduction, often add a supporting electrolyte to enable efficient operation. The prototypical case is that of anion-exchange-membrane water electrolyzers (AEMWEs), where addition of an alkali metal solution improves performance. However, the specific mechanism of this performance improvement is currently unknown. This work investigates the functionality of the alkali metal solution in AEMWEs using experiments and mathematical models. The results show that additional hydroxide plays a key role not only in ohmic resistance of the membrane and catalyst layer but also in the reaction kinetics. The modeling suggests that the added liquid electrolyte creates an additional electrochemical interface with the electrocatalyst that provides ion-transport pathways and distributes product gas bubbles; the total effective electrochemical active surface area in the cell with 1 M KOH is 5 times higher than that of the cell with DI water. In the cell with 1 M KOH, more than 80\% of the reaction current is associate with the liquid electrolyte. These results indicate the importance of high pH of electrolyte and catalyst/electrolyte interface in AEMWEs. The understanding of the functionality of the alkali metal solution presented in this study should help guide the design and optimization of AEMWEs.}, keywords = {alkali metal solutions, anion-exchange-membrane water electrolyzers, Energy Sciences, energy storage, liquid electrolyte, solid-state devices}, issn = {0013-4651}, doi = {10.1149/1945-7111/ac0019}, author = {Jiangjin Liu and Zhenye Kang and Dongguo Li and Magnolia Pak and Shaun M. Alia and Cy Fujimoto and Guido Bender and Yu Seung Kim and Adam Z. Weber} } @article {1120, title = {Outstanding Properties and Performance of CaTi0.5Mn0.5O3{\textendash}δ for Solar-Driven Thermochemical Hydrogen Production}, journal = {Matter}, volume = {4}, year = {2021}, pages = {688-708}, keywords = {inorganic perovskite, oxygen non-stoichiometry, phase transition, solar fuel, thermo-kinetic limit, thermochemical hydrogen production, thermodynamic properties}, doi = {https://doi.org/10.1016/j.matt.2020.11.016}, author = {X. Qian and J. He and E. Mastronardo and B. Baldassarri and W. Yuan and C. Wolverton and S. M. Haile} } @article {1166, title = {The oxygen partial pressure in solid oxide electrolysis cells with multilayer electrolytes}, journal = {Acta Materialia}, volume = {213}, year = {2021}, pages = {116928}, abstract = {A number of degradation mechanisms have been observed during the long-term operation of solid oxide electrolysis cells (SOEC). Using an electrolyte charge carrier transport model and a diffuse interface treatment for a multilayer electrolytes, we quantify the oxygen potentials across the electrolyte and thereby provide insights into these degradation mechanisms. Our model describes the transport of charge carriers in the electrolyte when the oxygen partial pressure is extremely low by accounting for the spatial variation of the concentration of oxygen vacancies in the electrolyte which is closely related to the degradation of the SOEC near the interface of hydrogen electrode and electrolyte. Moreover, we identify four quantities that characterize the distribution of oxygen partial pressure in the electrolyte, which are directly related to the degradation mechanisms in the electrolyte as well, and give analytical estimates for them. These analytical expressions provide guidance on the parameters that need to be controlled to suppress the degradation observed in the electrolyte.}, keywords = {Diffuse interface model, Multilayer electrolyte, Oxygen partial pressure, solid oxide electrolysis cell}, issn = {1359-6454}, doi = {https://doi.org/10.1016/j.actamat.2021.116928}, url = {https://www.sciencedirect.com/science/article/pii/S1359645421003086}, author = {Qian Zhang and Qin-Yuan Liu and Beom-Kyeong Park and Scott Barnett and Peter Voorhees} } @article {1113, title = {Performance and Durability of Anion Exchange Membrane Water Electrolyzers Using Down-Selected Polymer Electrolytes}, journal = {Journal of Materials Chemistry A}, year = {2021}, pages = {22670-22683}, doi = {https://doi.org/10.1039/D1TA06869E}, author = {A. R. Motz and D. Li and A. Keane and L. D. Manriquez and E. J. Park and S. Maurya and H. Chung and C. Fujimoto and J. Jeon and M. K. Pagels and C. Bae and K. E. Ayers and Y. S. Kim} } @article {1116, title = {Performance and Limits of 2.0 eV Bandgap CuInGaS2 Solar Absorber Integrated With CdS Buffer on F:SnO2 Substrate for Multijunction Photovoltaic and Photoelectrochemical Water Splitting Devices}, volume = {2}, year = {2021}, pages = {5752-5763}, doi = {https://doi.org/10.1039/D1MA00570G}, author = {N. Gaillard and W. Septina and J. Varley and T. Ogitsu and K. K. Ohtaki and H. A. Ishii and J. P. Bradley and C. Muzzillo and K. Zhu and F. Babbe and J. Cooper} } @article {1162, title = {Performance Indicators for Benchmarking Solar Thermochemical Fuel Processes and Reactors}, journal = {Frontiers in Energy Research}, volume = {9}, year = {2021}, abstract = {Concentrated solar energy offers a source for renewable high-temperature process heat that can be used to efficiently drive endothermic chemical processes, converting the entire spectrum of solar radiation into chemical energy. In particular, solar-driven thermochemical processes for the production of fuels include reforming of methane and other hydrocarbons, gasification of biomass, coal, and other carbonaceous feedstock, and metal oxide redox cycles for splitting H2O and CO2. A notable issue in the development of these processes and their associated solar reactors is the lack of consistent reporting methods for experimental demonstrations and modelling studies, which complicates the benchmarking of the corresponding technologies. In this work we formulate dimensionless performance indicators based on mass and energy balances of such reacting systems, namely: energy efficiency, conversion extent, selectivity, and yield. Examples are outlined for the generic processes mention above. We then provide guidelines for reporting on such processes and reactors and suggest performance benchmarking on four key criteria: energy efficiency, conversion extent, product selectivity, and performance stability.}, keywords = {benchmarking, concentrated solar power, solar fuels and chemicals, solar reactors, thermochemical processes}, issn = {2296-598X}, doi = {10.3389/fenrg.2021.677980}, url = {https://www.frontiersin.org/article/10.3389/fenrg.2021.677980}, author = {Bulfin, Brendan and Miranda, Miguel and Steinfeld, Aldo} } @article {1118, title = {Reduction Thermodynamics of Sr1-xCexMnO3 and CexSr2-xMnO4 Perovskites for Solar Thermochemical Hydrogen Production}, journal = {Energy Technology}, year = {2021}, doi = {https://doi.org/10.1002/ente.202100515}, author = {A. M. Bergeson-Keller and M. D. Sanders and R. P. O{\textquoteright}Hayre} } @article {1164, title = {Regulation of Cathode Mass and Charge Transfer by Structural 3D Engineering for Protonic Ceramic Fuel Cell at 400 {\textdegree}C (Adv. Funct. Mater. 33/2021)}, journal = {Advanced Functional Materials}, volume = {31}, year = {2021}, pages = {2170244}, abstract = {3D Engineering In article number 2102907, Wei Wu, Meng Zhou, Dong Ding, and co-workers develop a 3D engineered cathode to enhance oxygen reduction reaction kinetics on a proton-conducting fuel cell at <600 {\textdegree}C. The results demonstrate remarkable cell performance at 400{\textendash}600 {\textdegree}C by effectively regulating the mass and charge transfer through the electrode and across the interface of electrolyte and electrode.}, keywords = {3D engineering, charge transfer, mass transfer, oxygen reduction reaction, p-SOEC, protonic ceramic fuel cells}, doi = {https://doi.org/10.1002/adfm.202170244}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202170244}, author = {Bian, Wenjuan and Wu, Wei and Gao, Yipeng and Gomez, Joshua Y. and Ding, Hanping and Tang, Wei and Zhou, Meng and Ding, Dong} } @article {1121, title = {Techno-Economic Analysis of Thermochemical Water-Splitting System for Co-Production of Hydrogen and Electricity}, journal = {International Journal of Hydrogen Energy}, volume = {46}, year = {2021}, pages = {1656-1670}, keywords = {Techno-economic analysis}, doi = {https://doi.org/10.1016/j.ijhydene.2020.10.060}, author = {V. K. Budama and N. G. Johnson and I. Ermanoski and E. B. Stechel} } @article {1177, title = {Thin film growth effects on electrical conductivity in entropy stabilized oxides}, journal = {Journal of the European Ceramic Society}, volume = {41}, year = {2021}, pages = {2617-2624}, abstract = {Entropy stabilization has garnered significant attention as a new approach to designing novel materials. Much of the work in this area has focused on bulk ceramic processing, leaving entropy-stabilized thin films relatively under-explored. Following an extensive multi-variable investigation of polycrystalline (Mg0.2Co0.2Ni0.2Cu0.2Zn0.2)O thin films deposited via pulsed laser deposition (PLD), it is shown here that substrate temperature and deposition pressure have strong and repeatable effects on film texture and lattice parameter. Further analysis shows that films deposited at lower temperatures and under lower oxygen chamber pressure are \~{}40{\texttimes} less electrically resistive than otherwise identical films grown at higher temperature and pressure. Annealing these films in an oxygen-rich environment increases their electrical resistivity to match that of the films grown at higher temperatures and pressures. Because of this, the electric conductivity is hypothesized to be the result of polaron hopping mediated by transition metal valence changes which compensate for oxygen off-stoichiometry.}, keywords = {electrical conductivity, Entropy, oxide, Phase, Polycrystalline oxide thin films, Pulsed laser deposition, STCH, Thin film}, issn = {0955-2219}, doi = {https://doi.org/10.1016/j.jeurceramsoc.2020.12.021}, url = {https://www.sciencedirect.com/science/article/pii/S0955221920309900}, author = {V. Jacobson and D. Diercks and B. To and A. Zakutayev and G. Brennecka} } @article {1080, title = {Addressing the Stability Gap in Photoelectrochemistry: Molybdenum Disulfide Protective Catalysts for Tandem III{\textendash}V Unassisted Solar Water Splitting}, journal = {ACS Energy Letters}, year = {2020}, month = {07/2020}, pages = {2631-2640}, doi = {10.1021/acsenergylett.0c01132}, url = {https://doi.org/10.1021/acsenergylett.0c01132}, author = {Micha Ben-Naim and Reuben J. Britto and Chase W. Aldridge and Rachel Mow and Myles A. Steiner and Adam C. Nielander and Laurie A. King and Daniel J. Friedman and Todd G. Deutsch and James L. Young and Thomas F. Jaramillo} } @article {1171, title = {Enhancement of Ni-(Y2O3)0.08(ZrO2)0.92 fuel electrode performance by infiltration of Ce0.8Gd0.2O2-: δ nanoparticles}, journal = {Journal of Materials Chemistry A}, volume = {8}, year = {2020}, note = {Funding Information: The authors gratefully acknowledge research support from the HydroGEN Advanced Water Splitting Materials Consortium, established as part of the Energy Materials Network under the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Fuel Cell Technologies Office, under Award Number DE-0008079. The electrochemical modeling work was supported nancially by the Department of Energy National Energy Technology Laboratory under Prime Award Number DE-FE0027584 to FuelCell Energy, Inc., and under Subaward to Northwestern University. Some of the microstructural characterization was supported by National Science Foundation grants DMR-1506925 and DMR-1912530. Publisher Copyright: {\textcopyright} 2020 The Royal Society of Chemistry.}, pages = {4099{\textendash}4106}, abstract = {This paper addresses the use of Ce0.8Gd0.2O2-δ (GDC) infiltration into the Ni-(Y2O3)0.08(ZrO2)0.92 (YSZ) fuel electrode of solid oxide cells (SOCs) for improving their electrochemical performance in fuel cell and electrolysis operation. Although doped ceria infiltration into Ni-YSZ has recently been shown to improve the electrode performance and stability, the mechanisms defining how GDC impacts electrochemical characteristics are not fully delineated. Furthermore, the electrochemical characteristics have not yet been determined over the full range of conditions normally encountered in fuel cell and electrolysis operation. Here we present a study of both symmetric and full cells aimed at understanding the electrochemical mechanisms of GDC-modified Ni-YSZ over a wide range of fuel compositions and temperatures. Single-step GDC infiltration at an appropriate loading substantially reduced the polarization resistance of Ni-YSZ electrodes in electrolyte-supported cells, as measured using electrochemical impedance spectroscopy (EIS) at various temperatures (600-800 {\textdegree}C) in a range of H2O-H2 mixtures (3-90 vol\% H2O). Fuel-electrode-supported cells had significant concentration polarization due to the thick Ni-YSZ supports. A distribution of relaxation times approach is used to develop a physically-based electrochemical model; the results show that GDC reduces the reaction resistance associated with three-phase boundaries, but also appears to improve oxygen transport in the electrode. Increasing the H2O fraction in the H2-H2O fuel mixture reduced both the three-phase boundary resistance and the gas diffusion resistance for Ni-YSZ; with GDC infiltration, the electrode resistance showed less variation with fuel composition. GDC infiltration improved the performance of fuel-electrode-supported full cells, which yielded a maximum power density of 2.28 W cm-2 in fuel cell mode and an electrolysis current density at 1.3 V of 2.22 A cm-2, both at 800 {\textdegree}C.}, keywords = {HTE; SOEC; Yttria-stabilized zirconia}, issn = {2050-7488}, doi = {10.1039/c9ta12316d}, author = {Park, Beom Kyeong and Roberto Scipioni and Dalton Cox and Barnett, Scott A.} } @article {1126, title = {Favorable Redox Thermodynamics of SrTi0.5Mn0.5O3-δ in Solar Thermochemical Water Splitting}, journal = {Chemistry of Materials}, volume = {32}, year = {2020}, pages = {9335-9346}, keywords = {Cubic perovskite, Modeling, Perovskite, SrTi0.5Mn0.5O3-δ}, doi = {https://doi.org/10.1021/acs.chemmater.0c03278}, author = {X. Qian and J. He and E. Mastronardo and B. Baldassarri and C. Wolverton and S. M. Haile} } @article {1087, title = {Highly efficient and durable III{\textendash}V semiconductor-catalyst photocathodes via a transparent protection layer}, journal = {Sustainable Energy Fuels}, volume = {4}, year = {2020}, pages = {1437-1442}, abstract = {

Durable performance and high efficiency in solar-driven water splitting are great challenges not yet co-achieved in photoelectrochemical (PEC) cells. Although photovoltaic cells made from III{\textendash}V semiconductors can achieve high optical{\textendash}electrical conversion efficiency, their functional integration with electrocatalysts and operational lifetime remain great challenges. Herein, an ultra-thin TiN layer was used as a diffusion barrier on a buried junction n+p-GaInP2 photocathode, to enable elevated temperatures for subsequent catalyst growth of Ni5P4 as nano-islands without damaging the GaInP2 junction. The resulting PEC half-cell showed negligible absorption loss, with saturated photocurrent density and H2 evolution equivalent to the benchmark photocathode decorated with PtRu catalysts. High corrosion-resistant Ni5P4/TiN layers showed undiminished photocathode operation over 120 h, exceeding previous benchmarks. Etching to remove electrodeposited copper, an introduced contaminant, restored full performance, demonstrating operational ruggedness. The TiN layer expands the synthesis conditions and protects against corrosion for stable operation of III{\textendash}V PEC devices, while the Ni5P4 catalyst replaces costly and scarce noble metal catalysts.

}, doi = {10.1039/C9SE01264H}, url = {http://dx.doi.org/10.1039/C9SE01264H}, author = {Shinjae Hwang and James L. Young and Rachel Mow and Anders B. Laursen and Mengjun Li and Hongbin Yang and Philip E. Batson and Martha Greenblatt and Myles A. Steiner and Daniel Friedman and Todd G. Deutsch and Eric Garfunkel and G. Charles Dismukes} } @article {1172, title = {Highly quaternized polystyrene ionomers for high performance anion exchange membrane water electrolysers}, journal = {Nature Energy}, volume = {5}, year = {2020}, month = {3}, keywords = {LTE; AEM electrolysis; Novel ionomer}, doi = {10.1038/s41560-020-0577-x}, author = {Kim, Yu Seung and Li, Dongguo and Park, Eun Joo and Wenlei, Zhu and Qiurong, Shi and Zhou, Yang and Tian, Hangyu and Lin, Yuehe and Serov, Alexey and Zulevi, Barr and Baca, Ehren Donel and Fujimoto, Cy and Chung, Hoon} } @article {1124, title = {High-Throughput Analysis of Materials for Chemical Looping Processes}, journal = {Advanced Energy Materials}, volume = {10}, year = {2020}, keywords = {chemical looping, high-throughput screening, machine learning, redox catalysis}, doi = {https://doi.org/10.1002/aenm.202000685}, author = {N. R. Singstock and C. J. Bartel and A. M. Holder and C. B. Musgrave} } @article {1173, title = {Interfacial Electromechanics Predicts Phase Behavior of 2D Hybrid Halide Perovskites}, journal = {ACS Nano}, volume = {14}, year = {2020}, note = {PMID: 32073821}, pages = {3353-3364}, keywords = {PEC; Perovskites; Modeling}, doi = {10.1021/acsnano.9b09105}, url = {https://doi.org/10.1021/acsnano.9b09105}, author = {Price, Christopher C. and Blancon, Jean-Christophe and Mohite, Aditya D. and Shenoy, Vivek B.} } @article {1128, title = {Oxidation Kinetics of Hercynite Spinels for Solar Thermochemical Fuel Production}, journal = {Chemical Engineering Journal}, volume = {401}, year = {2020}, keywords = {Hercynite, In situ XPS, Reaction kinetics, Solar thermal, Thermochemical analysis}, doi = {https://doi.org/10.1016/j.cej.2020.126015}, author = {S. L. Millican and I. Androshchuk and J. T. Tran and R. M. Trottier and A. Bayon and Y. Al Salik and H. Idriss and C. B. Musgrave and A. W. Weimer} } @article {1123, title = {Predicting Spinel Disorder and Its Effect on Oxygen Transport Kinetics in Hercynite}, journal = {ACS Applied Materials \& Interfaces}, volume = {12}, year = {2020}, pages = {23831-23843}, keywords = {Hercynite, Spinel}, doi = {https://doi.org/10.1021/acsami.0c02819}, author = {R. M. Trottier and Z. J. L. Bare and S. L. Millican and C. B. Musgrave} } @article {1175, title = {On the role of the zirconia/ceria interface in the degradation of solid oxide electrolysis cells}, journal = {Applied Physics Letters}, volume = {117}, year = {2020}, pages = {123906}, keywords = {INL; o-SOEC}, doi = {10.1063/5.0016478}, url = {https://doi.org/10.1063/5.0016478}, author = {Zhang,Qian and Park,Beom-Kyeong and Barnett,Scott and Voorhees,Peter} } @article {1176, title = {Self-sustainable protonic ceramic electrochemical cells using a triple conducting electrode for hydrogen and power production}, journal = {Nature Communications}, volume = {11}, year = {2020}, month = {4}, keywords = {HTE; SOEC; Proton exchange membrane electrolysis cell; PrNi0.5Co0.5O3-δ perovskite}, doi = {10.1038/s41467-020-15677-z}, author = {Ding, Hanping and Wu, Wei and Jiang, Chao and Ding, Yong and Bian, Wenjuan and Hu, Boxun and Singh, Prabhakar and Orme, Christopher J. and Wang, Lucun and Zhang, Yunya and Ding, Dong} } @article {1178, title = {Tungsten oxide-coated copper gallium selenide sustains long-term solar hydrogen evolution}, journal = {Sustainable Energy \& Fuels}, volume = {5}, year = {2020}, month = {12}, keywords = {CuGaSe, durability, PEC, Photocathode, Pt hydrogen evolution catalyst, Tungsten oxide protective coating}, doi = {10.1039/d0se00487a}, author = {Palm, David W. and Muzzillo, Christopher P. and Ben-Naim, Micha and Khan, Imran and Gaillard, Nicolas and Jaramillo, Thomas F.} } @article {1179, title = {Understanding of A-site deficiency in layered perovskites: promotion of dual reaction kinetics for water oxidation and oxygen reduction in protonic ceramic electrochemical cells}, journal = {J. Mater. Chem. A}, volume = {8}, year = {2020}, pages = {14600-14608}, abstract = {Protonic ceramic electrochemical cells (PCECs) are promising solid-state energy conversion devices which enable the conversion of energy between electricity and hydrogen at intermediate temperatures. Rapid conversion between chemical and electrical energy via PCEC technology will assist in overcoming grand challenges in energy storage. To achieve highly efficient reversible operation between hydrogen production and electricity generation, boosting water-oxidation and oxygen reduction activities of the oxygen electrode while maintaining the durable operation is one of the early-stage technical opportunities. In this study, an A-site deficient layered perovskite (PrBa0.8Ca0.2)0.95Co2O6-δ has been developed as an oxygen electrode for a PCEC which presents superior electrochemical performances. The electrolysis current density reached as high as -0.72 A cm-2 at 1.3 V, and a peak power density of 0.540 W cm-2 was obtained at 600 {\textdegree}C in electrolysis and fuel cell mode, respectively. The PCEC with the new electrode shows good durability under practical operating conditions for 160 hours in both operating modes with no observable degradation. The reversibility between the electrolysis and fuel cell mode is also successfully demonstrated.}, keywords = {Durability; HTE; Layered perovskite; Protonic ceramic electrochemical cells}, doi = {10.1039/D0TA05137C}, url = {http://dx.doi.org/10.1039/D0TA05137C}, author = {Tang, Wei and Ding, Hanping and Bian, Wenjuan and Wu, Wei and Li, Wenyuan and Liu, Xingbo and Gomez, Joshua Y. and Regalado Vera, Clarita Y. and Zhou, Meng and Ding, Dong} } @article {1061, title = {Assessment of co-sintering as a fabrication approach for metal-supported proton-conducting solid oxide cells}, journal = {Solid State Ionics}, volume = {332}, year = {2019}, month = {04/2019}, pages = {25-33}, abstract = {

Published on April 1st, 2019. Proton conducting oxide electrolyte materials could potentially lower the operating temperature of metal-supported solid oxide cells (MS-SOCs) to the intermediate range 400 to 600 {\textdegree}C. The porous metal substrate provides the advantages of MS-SOCs such as high thermal and redox cycling tolerance, low-cost of structural materials, and mechanical ruggedness. In this work, viability of co-sintering fabrication of metal-supported proton conducting solid oxide cells is investigated. Candidate proton conducting oxides including perovskite oxides BaZr0.7Ce0.2Y0.1O3-δ, SrZr0.5Ce0.4Y0.1O3-δ, and Ba3Ca1.18Nb1.82O9-δ, pyrochlore oxides La1.95Ca0.05Zr2O7-δ and La2Ce2O7, and acceptor doped rare-earth ortho-niobate La0.99Ca0.01NbO4 are synthesized via solid state reactive or sol-gel methods. These ceramics are sintered at 1450 {\textdegree}C in reducing environment alone and supported on Fe-Cr alloy metal support, and their key characteristics such as phase formation, sintering property, and chemical compatibility with metal support are determined. Most electrolyte candidates suffer from one or more challenges identified for this fabrication approach, including: phase decomposition in reducing atmosphere, evaporation of electrolyte constituents, contamination of the electrolyte with Si and Cr from the metal support, and incomplete electrolyte sintering. In contrast, La0.99Ca0.01NbO4 is found to be highly compatible with the metal support and co-sintering processing in reducing atmosphere. A metal-supported cell is fabricated with La0.99Ca0.01NbO4 electrolyte, ferritic stainless steel support, Pt air electrode and nanoparticulate ceria-Ni hydrogen electrocatalyst. The total resistance is 50 Ω{\textperiodcentered}cm2 at 600 {\textdegree}C. This work clearly demonstrates the challenges, opportunities, and breakthrough of metal-supported proton-conducting solid oxide cells by co-sintering fabrication.

}, issn = {0167-2738}, doi = {10.1016/j.ssi.2019.01.004}, url = {http://www.sciencedirect.com/science/article/pii/S0167273818309263}, author = {Ruofan Wang and Conor Byrne and Michael C. Tucker} } @article {1182, title = {Conditions for stable operation of solid oxide electrolysis cells: oxygen electrode effects}, journal = {Energy Environ. Sci.}, volume = {12}, year = {2019}, pages = {3053-3062}, abstract = {Solid oxide electrolysis cells (SOECs) convert renewable electricity to fuels with efficiency substantially higher than other electrolysis technologies. However, questions remain regarding degradation mechanisms that limit SOEC long-term stability. One of the key degradation mechanisms is oxygen electrode delamination; although prior studies have improved the understanding of this mechanism, it is still difficult to predict how degradation depends on SOEC materials and operating conditions, i.e., temperature, voltage, and current density. Here we present a study aimed at developing a quantitative understanding of oxygen electrode delamination. Experimentally, a life test study of symmetric and full cells with yttria-stabilized zirconia (YSZ) electrolytes and Gd-doped ceria (GDC) barrier layers was done with three different perovskite oxygen electrode materials. Fracture was observed at the perovskite{\textendash}GDC interface above a critical current density and below a critical operating temperature. A theory is presented that combines a calculation of the effective oxygen pressure across the electrolyte with an estimation of the pressure required for fracture. Fracture is correctly predicted for a critical oxygen partial pressure of \~{}7200 atm and an associated electrode overpotential of \~{}0.2 V, occurring at the electrode/GDC interface because of the relatively low perovskite fracture toughness. Damage at the GDC/YSZ interface was also observed in some cases and explained by a peak in the oxygen pressure at this interface.}, keywords = {Gd-doped ceria, HTE, Perovskite, SOEC, Yttria-stabilized zirconia}, doi = {10.1039/C9EE01664C}, url = {http://dx.doi.org/10.1039/C9EE01664C}, author = {Park, Beom-Kyeong and Zhang, Qian and Voorhees, Peter W. and Barnett, Scott A.} } @article {1184, title = {Effect of direct-current operation on the electrochemical performance and structural evolution of Ni-YSZ electrodes}, journal = {Journal of Physics: Energy}, volume = {2}, year = {2019}, month = {12/2019}, pages = {014006}, abstract = {The effect of electrolysis operations on Ni-YSZ fuel electrode stability was studied at different current densities and fuel mixtures during 1000 h life tests. For a typical electrolysis mixture of 50\% H2/50\% H2O and 0.6 A cm-2 current density, cell ohmic resistance values were reasonably stable and no structural changes occurred. However, for more reducing conditions (97\% H2/3\% H2O), increasing the current density above 0.4 A cm-2 increased the ohmic resistance accompanied by significant electrolyte degradation including fracture and void formation at grain boundaries. Numerical analysis was carried out to determine the effective oxygen partial pressure across the electrolyte. The results show that the oxygen partial pressure values at high current density and low steam content may be low enough to reduce zirconia to form a Ni-Zr alloy product, initiating the observed electrolyte structural degradation.}, keywords = {durability, HTE, SOEC, Yttria-stabilized zirconia}, doi = {10.1088/2515-7655/ab59a6}, url = {https://doi.org/10.1088/2515-7655/ab59a6}, author = {Qinyuan Liu and Qian Zhang and Peter W Voorhees and Scott A Barnett} } @article {1185, title = {Ferritic stainless steel interconnects for protonic ceramic electrochemical cell stacks: Oxidation behavior and protective coatings}, journal = {International Journal of Hydrogen Energy}, volume = {44}, year = {2019}, pages = {25297-25309}, abstract = {Protonic ceramic fuel or electrolysis cells (PCFC/PCEC) have shown promising performance at intermediate temperatures. However, these technologies have not yet been demonstrated in a stack, hence the oxidation behavior of the metallic interconnect under relevant operating environments is unknown. In this work, ferritic stainless steels 430 SS, 441 SS, and Crofer 22 APU were investigated for their use as interconnect materials in the PCFC/PCEC stack. The bare metal sheets were exposed to a humidified air environment in the temperature range from 450~{\textdegree}C to 650~{\textdegree}C, to simulate their application in a PCFC cathode or PCEC anode. Breakaway oxidation with rapid weight gain and Fe outward diffusion/oxidation was observed on all the selected stainless steel materials. A protective coating is deemed necessary to prevent the metallic interconnect from oxidizing. To mitigate the observed breakaway oxidation, state-of-the-art protective coatings, Y2O3, Ce0.02Mn1.49Co1.49O4, CuMn1.8O4 and Ce/Co, were applied to the stainless steel sheets and their oxidation resistance was investigated. Dual atmosphere testing further validated the effectiveness of the protective coatings in realistic PCFC/PCEC environments, with a hydrogen gradient across the interconnect. Several combinations of metal and coating material were found to be viable for use as the interconnect for PCFC/PCEC stacks.}, keywords = {Dual atmosphere, Interconnect oxidation, Oxidation, Protective coatings, Protonic ceramic electrolysis cell, Protonic ceramic fuel cell}, issn = {0360-3199}, doi = {https://doi.org/10.1016/j.ijhydene.2019.08.041}, url = {https://www.sciencedirect.com/science/article/pii/S0360319919329581}, author = {Ruofan Wang and Zhihao Sun and Jung-Pyung Choi and Soumendra N. Basu and Jeffry W. Stevenson and Michael C. Tucker} } @inbook {1073, title = {HydroGEN Overview: A Consortium on Advanced Water Splitting Materials (AWSM)}, booktitle = {FY 2018 DOE Hydrogen and Fuel Cells Program Annual Progress Report}, year = {2019}, author = {Huyen N. Dinh and R Boardman and A.H. McDaniel and H Colon-Mercado and T. Ogitsu and A.Z. Weber} } @article {1065, title = {Initial approaches in benchmarking and round robin testing for proton exchange membrane water electrolyzers}, journal = {International Journal of Hydrogen Energy}, volume = {44}, year = {2019}, month = {04/2019}, pages = {9174-9187}, abstract = {

Published on April 5th, 2019. As ever-increasing amounts of renewable electricity enter the energy supply mix on a regional, national and international basis, greater emphasis is being placed on energy conversion and storage technologies to deal with the oscillations, excess and lack of electricity. Hydrogen generation via proton exchange membrane water electrolysis (PEMWE) is one technology that offers a pathway to store large amounts of electricity in the form of hydrogen. The challenges to widespread adoption of PEM water electrolyzers lie in their high capital and operating costs which both need to be reduced through R\&D. An evaluation of reported PEMWE performance data in the literature reveals that there are excessive variations of in situ performance results that make it difficult to draw conclusions on the pathway forward to performance optimization and future R\&D directions. To enable the meaningful comparison of in situ performance evaluation across laboratories there is an obvious need for standardization of materials and testing protocols. Herein, we address this need by reporting the results of a round robin test effort conducted at the laboratories of five contributors to the IEA Electrolysis Annex 30. For this effort a method and equipment framework were first developed and then verified with respect to its feasibility for measuring water electrolysis performance accurately across the various laboratories. The effort utilized identical sets of test articles, materials, and test cells, and employed a set of shared test protocols. It further defined a minimum skeleton of requirements for the test station equipment. The maximum observed deviation between laboratories at 1\ A\ cm-2 at cell temperatures of 60\ {\textdegree}C and 80\ {\textdegree}C was 27 and 20\ mV, respectively. The deviation of the results from laboratory to laboratory was 2{\textendash}3 times higher than the lowest deviation observed at one single lab and test station. However, the highest deviations observed were one-tenth of those extracted by a literature survey on similar material sets. The work endorses the urgent need to identify one or more reference sets of materials in addition to the method and equipment framework introduced here, to enable accurate comparison of results across the entire community. The results further imply that cell temperature control appears to be the most significant source of deviation between results, and that care must be taken with respect to break-in conditions and cell electrical connections for meaningful performance data.

}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2019.02.074}, url = {http://www.sciencedirect.com/science/article/pii/S0360319919306585}, author = {G. Bender and M. Carmo and T. Smolinka and A. Gago and N. Danilovic and M. Mueller and F. Ganci and A. Fallisch and P. Lettenmeier and K. A. Friedrich and K. Ayers and B. Pivovar and J. Mergel and D. Stolten} } @article {1187, title = {Interfacial engineering of gallium indium phosphide photoelectrodes for hydrogen evolution with precious metal and non-precious metal based catalysts}, journal = {Journal of Materials Chemistry A}, volume = {7}, year = {2019}, pages = {16821-16832}, abstract = {Gallium indium phosphide (GaInP2) is a semiconductor with promising optical and electronic properties to serve as the large bandgap, top junction in a dual absorber tandem solar water splitting device. Poor intrinsic catalytic ability and surface corrosion in aqueous electrolyte remain key obstacles. Significant progress has been made developing thin-film protection layers and active catalysts for photoelectrochemical devices, but combining these into a catalytic protection layer that can provide long-term stability without sacrificing performance has proven difficult due, in large part, to challenges in developing active and stable interfaces. In this work, we demonstrate that a nanoscale molybdenum disulfide (MoS2) film functions both as an effective protection layer and excellent hydrogen evolution catalyst for GaInP2 photocathodes, with only a \~{}10\% loss in initial light-limited current density after 100 h, and a photocurrent onset potential better than that of the same state-of-the-art device with a platinum{\textendash}ruthenium catalyst. Using transient photoreflectance spectroscopy, we probed the carrier dynamics of these photocathodes and show that the MoS2 coated device exhibits improved electron transfer at the surface interface compared to the PtRu catalyzed device. These MoS2 protected devices are among the most active and stable single-absorber photocathodes for solar water splitting to date and offer a promising pathway towards generating hydrogen with high efficiency and significant longevity.}, keywords = {durability, GaInP2, III-V, MoS2 hydrogen evolution catalyst, MoS2 protective coating, PEC, Photocathode}, doi = {10.1039/C9TA05247J}, url = {http://dx.doi.org/10.1039/C9TA05247J}, author = {Britto, Reuben J. and Young, James L. and Yang, Ye and Steiner, Myles A. and LaFehr, David T. and Friedman, Daniel J. and Beard, Mathew and Deutsch, Todd G. and Jaramillo, Thomas F.} } @article {1067, title = {Investigation of porous transport layer parameters for proton exchange membrane water electrolysis}, year = {2019}, abstract = {
  1. Presentation
  2. Investigation of porous transport layer parameters for proton exchange membrane water electrolysis
  3. Presenter
    Zhenye Kang
  4. Contributor
    Shaun M. Alia
  5. Contributor
    James L. Young
  6. Contributor
    Guido Bender
  7. LTE
  8. 2019
  9. Hilton Atlanta, Atlanta, GA, USA
  10. 236th ECS Meeting
  11. http://ma.ecsdl.org/content/MA2019-02/37/1747.short
  12. 11/6/2019, 10:47:45 AM
  13. 12/6/2019, 1:28:14 PM
Abstract
Published on October 17th, 2019 Hydrogen production through proton exchange membrane water electrolysis (PEMWE) is regarded as a very promising technology that offers a highly efficient and robust path to store electrical energy in form of hydrogen and further enables the integration of renewable energy into the electrical grid 1-3. The total cell voltage of a single PEM water electrolyzer cell is composed of the open circuit voltage, activation overpotential, diffusion overpotential, and ohmic loss overpotential 4. The total voltage of the cell can be expressed as Eq(1) 5. V=V_OCV+V_act+V_ohm+V_diff (1) Where V_OCV is the Nernst potential which is also called the reversible voltage and can be calculated from the Nernst equation or Gibbs free energy, V_act is the activation overpotential due to the electrochemical reaction and it represents the overpotential to drive the electron transfer and electrochemical reaction kinetics as described by the Butler-Volmer model, V_ohm is the ohmic overpotential caused by the resistances of the electronic/ionic components and interfacial contact resistances, and V_diff is the diffusion overpotential related to mass transport. Porous transport layers (PTLs) are key components in PEMWE. They facilitate mass transport, thermal and electrical conduction, and are required to sustain a good contact with adjacent components 6-8. It is expected that various PTLs with different structures and wettability exhibit nonidentical performance in PEMWE. In this study, a general model is established to investigate the PTL parameters of four inherently different PTLs, including non-treated Toray paper, PTFE treated Toray paper, sintered titanium particles and Ti felt. SEM images highlighting the structures of these PTL materials are shown in Figure 1. The materials, which differed in thickness, porosity, material and composition were evaluated with identical MEAs over a range of operating conditions for model validation. The resulting data indicate that the hydrophobic additives in the Toray paper will decrease the PEMWE performance due to increased mass transport loss and ohmic loss. Ti felt with similar thickness and porosity as non-treated Toray paper showed slightly reduced performance due to its higher ohmic loss. Sintered Ti particle PTLs exhibit much higher ohmic resistance than Ti felt and nontreated Toray paper, which may be attributed to its significantly larger thickness and/or an increased contact resistance. The experimental data was employed to validate the MATLAB/Simulink model which enables the simulation of the contribution of each overpotential. The model was used to successfully describe the effects of PTFE loading on PEMWE performance, as shown in Figure 2. The hydrophobic treatment resulted, as expected, in detrimental performance effects. The diffusion loss of a 20\% PTFE treated Toray paper is significantly higher than that of the nontreated PTLs (Figure 2). The modeling results also indicate that the change of the wettability of the PTLs by hydrophobic additives/agents, impacted not only the diffusion loss significantly, but also affected the ohmic loss and activation loss. This was specifically detrimental to PEMWE cell performance when operating at high current densities. The model that was validated in this study can be used to predict the effects of key PTL parameters and utilized to optimize PEMWE performance.
}, url = {http://ma.ecsdl.org/content/MA2019-02/37/1747.short}, author = {Zhenye Kang and Shaun M. Alia and James L. Young and Guido Bender} } @article {1089, title = {Molybdenum Disulfide Catalytic Coatings via Atomic Layer Deposition for Solar Hydrogen Production from Copper Gallium Diselenide Photocathodes}, journal = {ACS Applied Energy Materials}, volume = {2}, year = {2019}, pages = {1060-1066}, abstract = {

We demonstrate that applying atomic layer deposition-derived molybdenum disulfide (MoS2) catalytic coatings on copper gallium diselenide (CGSe) thin film absorbers can lead to efficient wide band gap photocathodes for photoelectrochemical hydrogen production. We have prepared a device that is free of precious metals, employing a CGSe absorber and a cadmium sulfide (CdS) buffer layer, a titanium dioxide (TiO2) interfacial layer, and a MoS2 catalytic layer. The resulting MoS2/TiO2/CdS/CGSe photocathode exhibits a photocurrent onset of +0.53 V vs RHE and a saturation photocurrent density of -10 mA cm{\textendash}2, with stable operation for \>5 h in acidic electrolyte. Spectroscopic investigations of this device architecture indicate that overlayer degradation occurs inhomogeneously, ultimately exposing the underlying CGSe absorber.

}, doi = {10.1021/acsaem.8b01562}, url = {https://doi.org/10.1021/acsaem.8b01562}, author = {Thomas R. Hellstern and David W. Palm and James Carter and Alex D. DeAngelis and Kimberly Horsley and Lothar Weinhardt and Wanli Yang and Monika Blum and Nicolas Gaillard and Clemens Heske and Thomas F. Jaramillo} } @article {1074, title = {New tolerance factor to predict the stability of perovskite oxides and halides}, journal = {Science Advances}, volume = {5}, year = {2019}, note = {

Copyright {\textcopyright} 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY).. This is an open-access article distributed under the terms of the Creative Commons Attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

}, month = {02/2019}, pages = {eaav0693}, abstract = {

Published on February 1st, 2019. Predicting the stability of the perovskite structure remains a long-standing challenge for the discovery of new functional materials for many applications including photovoltaics and electrocatalysts. We developed an accurate, physically interpretable, and one-dimensional tolerance factor, τ, that correctly predicts 92\% of compounds as perovskite or nonperovskite for an experimental dataset of 576 ABX3 materials (X = O2-, F-, Cl-, Br-, I-) using a novel data analytics approach based on SISSO (sure independence screening and sparsifying operator). τ is shown to generalize outside the training set for 1034 experimentally realized single and double perovskites (91\% accuracy) and is applied to identify 23,314 new double perovskites (A2BB'X6) ranked by their probability of being stable as perovskite. This work guides experimentalists and theorists toward which perovskites are most likely to be successfully synthesized and demonstrates an approach to descriptor identification that can be extended to arbitrary applications beyond perovskite stability predictions. Simple and interpretable data-driven descriptor accurately predicts the synthesizability of single and double perovskites.

}, issn = {2375-2548}, doi = {10.1126/sciadv.aav0693}, url = {https://advances.sciencemag.org/content/5/2/eaav0693}, author = {Christopher J. Bartel and Christopher Sutton and Bryan R. Goldsmith and Runhai Ouyang and Charles B. Musgrave and Luca M. Ghiringhelli and Matthias Scheffler} } @article {1075, title = {Phase Identification of the Layered Perovskite CexSr2{\textendash}xMnO4 and Application for Solar Thermochemical Water Splitting}, journal = {Inorganic Chemistry}, volume = {58}, year = {2019}, pages = {7705-7714}, abstract = {

Published on June 17th, 2019. Ruddlesden{\textendash}Popper (layered perovskite) phases are attracting significant interest because of their unique potential for many applications requiring mixed ionic and electronic conductivity. Here we report a new, previously undiscovered layered perovskite of composition, CexSr2{\textendash}xMnO4 (x = 0.1, 0.2, and 0.3). Furthermore, we demonstrate that this new system is suitable for solar thermochemical hydrogen production (STCH). Synchrotron radiation X-ray diffraction and transmission electron microscopy are performed to characterize this new system. Density functional theory calculations of phase stability and oxygen vacancy formation energy (1.76, 2.24, and 2.66 eV/O atom, respectively with increasing Ce content) reinforce the potential of this phase for STCH application. Experimental hydrogen production results show that this materials system produces 2{\textendash}3 times more hydrogen than the benchmark STCH oxide ceria at a reduction temperature of 1400 {\textdegree}C and an oxidation temperature of 1000 {\textdegree}C.

}, issn = {0020-1669}, doi = {10.1021/acs.inorgchem.8b03487}, url = {https://doi.org/10.1021/acs.inorgchem.8b03487}, author = {Debora R. Barcellos and Francisco G. Coury and Antoine Emery and Michael Sanders and Jianhua Tong and Anthony McDaniel and Christopher Wolverton and Michael Kaufman and Ryan O{\textquoteright}Hayre} } @article {1190, title = {Photoelectrochemical water splitting using strain-balanced multiple quantum well photovoltaic cells}, journal = {Sustainable Energy Fuels}, volume = {3}, year = {2019}, pages = {2837-2844}, abstract = {Starting from the classical GaInP/GaAs tandem photoelectrochemical water splitting device, higher solar-to-hydrogen efficiencies can be pursued by extending photon absorption to longer wavelengths. We incorporate strain-balanced GaInAs/GaAsP quantum wells into the bottom GaAs junction, to increase the range of photon absorption. The inclusion of 1.34 eV quantum wells in the depletion region of the bottom cell extends the absorption edge to 930 nm. With a corresponding increase in the thickness of the top cell for current matching, the light-limiting photocurrent increases by >8\%. The estimated solar-to-hydrogen efficiency is 13.6 {\textpm} 0.5\%, and we show a pathway to further improvement. With the semiconductor device remaining on the growth substrate, this quantum well architecture may enable improved stability and durability of the photoelectrochemical electrodes.}, keywords = {durability, National Renewable Energy Lab (NREL), PEC, photoelectrochemical water splitting}, doi = {10.1039/C9SE00276F}, url = {http://dx.doi.org/10.1039/C9SE00276F}, author = {Steiner, Myles A. and Barraugh, Collin D. and Aldridge, Chase W. and Alvarez, Isabel Barraza and Friedman, Daniel J. and Ekins-Daukes, Nicholas J. and Deutsch, Todd G. and Young, James L.} } @article {1078, title = {The role of decomposition reactions in assessing first-principles predictions of solid stability}, journal = {npj Computational Materials}, volume = {5}, year = {2019}, pages = {4}, abstract = {

Published on January 4th, 2019. The performance of density functional theory approximations for predicting materials thermodynamics is typically assessed by comparing calculated and experimentally determined enthalpies of formation from elemental phases, ΔHf. However, a compound competes thermodynamically with both other compounds and their constituent elemental forms, and thus, the enthalpies of the decomposition reactions to these competing phases, ΔHd, determine thermodynamic stability. We evaluated the phase diagrams for 56,791 compounds to classify decomposition reactions into three types: 1. those that produce elemental phases, 2. those that produce compounds, and 3. those that produce both. This analysis shows that the decomposition into elemental forms is rarely the competing reaction that determines compound stability and that approximately two-thirds of decomposition reactions involve no elemental phases. Using experimentally reported formation enthalpies for 1012 solid compounds, we assess the accuracy of the generalized gradient approximation (GGA) (PBE) and meta-GGA (SCAN) density functionals for predicting compound stability. For 646 decomposition reactions that are not trivially the formation reaction, PBE (mean absolute difference between theory and experiment (MAD)\ =\ 70\ meV/atom) and SCAN (MAD\ =\ 59\ meV/atom) perform similarly, and commonly employed correction schemes using fitted elemental reference energies make only a negligible improvement (~2 meV/atom). Furthermore, for 231 reactions involving only compounds (Type 2), the agreement between SCAN, PBE, and experiment is within ~35\ meV/atom and is thus comparable to the magnitude of experimental uncertainty.

}, issn = {2057-3960}, doi = {10.1038/s41524-018-0143-2}, url = {https://www.nature.com/articles/s41524-018-0143-2}, author = {Christopher J. Bartel and Alan W. Weimer and Stephan Lany and Charles B. Musgrave and Aaron M. Holder} } @article {1070, title = {Synthesis of Aromatic Anion Exchange Membranes by Friedel{\textendash}Crafts Bromoalkylation and Cross-Linking of Polystyrene Block Copolymers}, journal = {Macromolecules}, volume = {52}, year = {2019}, pages = {2139-2147}, abstract = {

Published on March 12th, 2019. Elastomeric anion exchange membranes (AEMs) were prepared by acid-catalyzed Friedel{\textendash}Crafts alkylation of the polystyrene block of polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (SEBS) using bromoalkylated tertiary alcohols and triflic acid as a catalyst, followed by amination with trimethylamine. This simple one-step bromoalkylation allowed convenient control of both the degree of functionalization and cation tether length by changing the molar ratio and the structure of the bromoalkylated tertiary alcohol. The resulting quaternary ammonium-functionalized ionic triblock SEBS copolymers showed a microphase-separated morphology on the 35 nm length scale. A series of AEMs with different ion exchange capacities and ion tether lengths were systematically investigated by comparing swelling and anion conductivity. Because the SEBS AEMs showed high swelling and low dimensional stability in water due to the rubbery nature of SEBS, the hard segment PS units were cross-linked by 1,6-hexanediamine for practical use. The cross-linking of SEBS AEMs reduced water uptake significantly (e.g., 155\% vs 28\%) and enhanced their mechanical properties. Because the backbone of the SEBS AEMs are composed of all carbon{\textendash}carbon bonds, they showed good alkaline stability, preserving their IEC and OH{\textendash} conductivity after testing in a 1 M NaOH solution at 80 {\textdegree}C for 500 h. Alkaline membrane fuel cell performance was evaluated with the cross-linked SEBS AEM, and a peak power density of 520 mW/cm2 was achieved at 60 {\textdegree}C under H2/O2 conditions.

}, issn = {0024-9297}, doi = {10.1021/acs.macromol.8b02355}, url = {https://doi.org/10.1021/acs.macromol.8b02355}, author = {Yong Yeob Jeon and Sungmin Park and Junyoung Han and Sandip Maurya and Angela D. Mohanty and Ding Tian and Nayan Saikia and Michael A. Hickner and Chang Y. Ryu and Mark E. Tuckerman and Stephen J. Paddison and Yu Seung Kim and Chulsung Bae} } @article {1098, title = {Wide-Bandgap Cu(In,Ga)S2 Photocathodes Integrated on Transparent Conductive F:SnO2 Substrates for Chalcopyrite-Based Water Splitting Tandem Devices}, journal = {ACS Applied Energy Materials}, volume = {2}, year = {2019}, month = {08/2019}, pages = {5515-5524}, abstract = {

Published on August 26th, 2019.

}, issn = {2574-0962, 2574-0962}, doi = {10.1021/acsaem.9b00690}, url = {http://pubs.acs.org/doi/10.1021/acsaem.9b00690}, author = {Nicolas Gaillard and Dixit Prasher and Marina Chong and Alexander Deangelis and Kimberly Horsley and Hope A. Ishii and John P. Bradley and Joel Varley and Tadashi Ogitsu} } @article {785, title = {BaCe 0.25 Mn 0.75 O 3-δ {\textemdash}a promising perovskite-type oxide for solar thermochemical hydrogen production}, journal = {Energy \& Environmental Science}, year = {2018}, note = {

{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n\ \n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright}

}, issn = {1754-5692, 1754-5706}, doi = {10.1039/C8EE01989D}, url = {http://xlink.rsc.org/?DOI=C8EE01989D}, author = {Debora R. Barcellos and Michael D. Sanders and Jianhua Tong and Anthony H. McDaniel and Ryan P. O{\textquoteright}Hayre} } @article {1062, title = {Cobalt-substituted SrTi0.3Fe0.7O3-δ: a stable high-performance oxygen electrode material for intermediate-temperature solid oxide electrochemical cells}, journal = {Energy \& Environmental Science}, volume = {11}, year = {2018}, month = {07/2018}, pages = {1870-1879}, abstract = {

Published on July 11th, 2018. A key need in the development of solid oxide cells (SOCs) is for electrodes that promote fast oxygen reduction and oxygen evolution reactions at reduced operating temperature (<=700 {\textdegree}C), with sufficient durability to allow operation over desired 40 000 h lifetimes. A wide range of electrode materials have been investigated, with some providing resistance low enough for cell operation below 700 {\textdegree}C, but it is generally found that the electrode performance degrades over time. Here we demonstrate an oxygen electrode material, Sr(Ti0.3Fe0.7-xCox)O3-δ (STFC), that provides a unique combination of excellent oxygen electrode performance and long-term stability. The addition of a relatively small amount of Co to Sr(Ti0.3Fe0.7)O3-δ, e.g., x = 0.07, reduces the electrode polarization resistance by \>2 times. The STFC electrode yields stable performance in both fuel cell and electrolysis modes at 1 A cm-2. The fundamental oxygen diffusion and surface exchange coefficients of STFC are determined, and shown to be substantially better than those of La0.6Sr0.4Co0.2Fe0.8O3-δ, the most widely used SOC oxygen electrode material. While other electrode materials have been shown to exhibit better oxygen transport coefficients than STFC, they do not match its stability.

}, doi = {10.1039/C8EE00449H}, url = {https://pubs.rsc.org/en/content/articlelanding/2018/ee/c8ee00449h}, author = {Shan-Lin Zhang and Hongqian Wang and Matthew Y. Lu and Ai-Ping Zhang and Liliana V. Mogni and Qinyuan Liu and Cheng-Xin Li and Chang-Jiu Li and Scott A. Barnett} } @article {1086, title = {High Efficiency Si Photocathode Protected by Multifunctional GaN Nanostructures}, journal = {Nano Letters}, volume = {18}, year = {2018}, pages = {6530-6537}, abstract = {

Published on October 10th, 2018. Photoelectrochemical water splitting is a clean and environmentally friendly method for solar hydrogen generation. Its practical application, however, has been limited by the poor stability of semiconductor photoelectrodes. In this work, we demonstrate the use of GaN nanostructures as a multifunctional protection layer for an otherwise unstable, low-performance photocathode. The direct integration of GaN nanostructures on n+{\textendash}p Si wafer not only protects Si surface from corrosion but also significantly reduces the charge carrier transfer resistance at the semiconductor/liquid junction, leading to long-term stability (\>100 h) at a large current density (\>35 mA/cm2) under 1 sun illumination. The measured applied bias photon-to-current efficiency of 10.5\% is among the highest values ever reported for a Si photocathode. Given that both Si and GaN are already widely produced in industry, our studies offer a viable path for achieving high-efficiency and highly stable semiconductor photoelectrodes for solar water splitting with proven manufacturability and scalability.

}, issn = {1530-6984}, doi = {10.1021/acs.nanolett.8b03087}, url = {https://doi.org/10.1021/acs.nanolett.8b03087}, author = {Srinivas Vanka and Elisabetta Arca and Shaobo Cheng and Kai Sun and Gianluigi A. Botton and Glenn Teeter and Zetian Mi} } @article {1097, title = {(Invited) HydroGEN: An AWSM Energy Materials Network}, journal = {ECS Transactions}, volume = {85}, year = {2018}, month = {05/2018}, pages = {3-14}, abstract = {

The HydroGEN (https://www.h2awsm.org/) energy materials network (EMN) aims to accelerate the research and development (R\&D) of advanced water splitting (AWS) technologies for clean, sustainable hydrogen production. Announced in October 2016, the HydroGEN EMN comprises six core National Laboratories and focuses on four AWS pathways: low- and high-temperature electrolysis, photoelectrochemical, and solar thermochemical water splitting. The HydroGEN consortium offers an extensive collection of materials research capabilities for addressing R\&D challenges in discovery and design, efficacy and efficiency, durability and cost. Leveraging the HydroGEN Consortium{\textquoteright}s technical experts and broad collection of unique resource capabilities is expected to advance the maturity and technology readiness levels in each advanced water splitting technology pathway.

}, issn = {1938-6737, 1938-5862}, doi = {10.1149/08511.0003ecst}, url = {http://ecst.ecsdl.org/content/85/11/3}, author = {James W. Vickers and Huyen N. Dinh and Katie Randolph and Adam Z. Weber and Anthony H. McDaniel and Richard Boardman and Tadashi Ogitsu and Hector Colon-Mercado and David Peterson and Eric L. Miller} } @article {1069, title = {Performance enhancement of PEM electrolyzers through iridium-coated titanium porous transport layers}, journal = {Electrochemistry Communications}, volume = {97}, year = {2018}, month = {12/2018}, pages = {96-99}, abstract = {

Published on December 1st, 2018. Titanium-based porous transport layers (PTL) used in polymer electrolyte membrane (PEM) water electrolyzers suffer from surface passivation (titanium oxidation), which increases the interface resistance between the PTL and electrode. For long-term operation, PTLs are typically coated with considerable amounts of platinum or gold to ensure reasonable performance profiles over time. Moreover, it is well known that the oxide forms of platinum and gold are not stable under electrolysis conditions. In this study, an easy and scalable method is introduced to protect the titanium PTL from passivation by sputtering very thin layers of iridium onto commercially-available titanium PTLs. The iridium layer reduces the overall ohmic resistance of the PTL/catalyst layer interface and improves the cell{\textquoteright}s performance to that achieved with carbon-based PTLs. The coating process homogeneously deposited iridium throughout the inner structure of the PTL. The findings of this study may lead to the use of iridium as a protective layer for titanium PTLs, potentially enable operation at increased cell voltages and lead to increased electrolyzer durability.

}, issn = {1388-2481}, doi = {10.1016/j.elecom.2018.10.021}, url = {http://www.sciencedirect.com/science/article/pii/S1388248118302741}, author = {Chang Liu and Marcelo Carmo and Guido Bender and Andreas Everwand and Thomas Lickert and James L. Young and Tom Smolinka and Detlef Stolten and Werner Lehnert} } @article {1076, title = {Physical descriptor for the Gibbs energy of inorganic crystalline solids and temperature-dependent materials chemistry}, journal = {Nature Communications}, volume = {9}, year = {2018}, month = {10/2018}, pages = {4168}, issn = {2041-1723}, doi = {10.1038/s41467-018-06682-4}, url = {https://www.nature.com/articles/s41467-018-06682-4}, author = {Christopher J. Bartel and Samantha L. Millican and Ann M. Deml and John R. Rumptz and William Tumas and Alan W. Weimer and Stephan Lany and Vladan Stevanovi{\'c} and Charles B. Musgrave and Aaron M. Holder} } @article {871, title = {Applications and limitations of two step metal oxide thermochemical redox cycles; a review}, journal = {J. Mater. Chem. A}, volume = {5}, year = {2017}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {18951-18966}, issn = {2050-7488, 2050-7496}, doi = {10.1039/C7TA05025A}, url = {http://xlink.rsc.org/?DOI=C7TA05025A}, author = {B. Bulfin and J. Vieten and C. Agrafiotis and M. Roeb and C. Sattler} } @article {801, title = {Characterizing Voltage Losses in an SO2 Depolarized Electrolyzer Using Sulfonated Polybenzimidazole Membranes}, journal = {Journal of The Electrochemical Society}, volume = {164}, year = {2017}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {F1591-F1595}, abstract = {Published on January 1st, 2017. The hybrid sulfur cycle has been investigated as a means to produce CO2-free hydrogen efficiently on a large scale through the decomposition of H2SO4 to SO2, O2, and H2O, and then electrochemically oxidizing SO2 back to H2SO4 with the cogeneration of H2. The net effect is the production of hydrogen and oxygen from water. Recently, sulfonated polybenzimidazoles (s-PBI) have been investigated as a replacement for Nafion due to the ability to offer increased process efficiency through the generation of higher acid concentrations at lower potentials. Here, we measure the acid concentrations and individual potential contributions toward the overall operating voltage seen in the SO2-depolarized-electrolyzer. We then determine model parameters necessary to predict voltage losses in a cell over a wide range of operating temperatures, pressures, currents and reactant flow rates.}, issn = {0013-4651, 1945-7111}, doi = {10.1149/2.1061714jes}, url = {http://jes.ecsdl.org/content/164/14/F1591}, author = {Taylor R. Garrick and Cody H. Wilkins and Andrew T. Pingitore and Jacob Mehlhoff and Alex Gulledge and Brian C. Benicewicz and John W. Weidner} } @article {1028, title = {Critical Review{\textemdash}Identifying Critical Gaps for Polymer Electrolyte Water Electrolysis Development}, journal = {Journal of The Electrochemical Society}, volume = {164}, year = {2017}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {F387-F399}, abstract = {Published on January 1st, 2017. Although polymer electrolyte water electrolyzers (PEWEs) have been used in small-scale (kW to tens of kW range) applications for several decades, PEWE technology for hydrogen production in energy applications (power-to-gas, power-to-fuel, etc.) requires significant improvements in the technology to address the challenges associated with cost, performance and durability. Systems with power of hundreds of kW or even MWs, corresponding to hydrogen production rates of around 10 to 20 kg/h, have started to appear in the past 5 years. The thin (\~{}0.2 mm) polymer electrolyte in the PEWE with low ohmic resistance, compared to the alkaline cell with liquid electrolyte, allows operation at high current densities of 1{\textendash}3 A/cm2 and high differential pressure. This article, after an introductory overview of the operating principles of PEWE and state-of-the-art, discusses the state of understanding of key phenomena determining and limiting performance, durability, and commercial readiness, identifies important {\textquoteleft}gaps{\textquoteright} in understanding and essential development needs to bring PEWE science \& engineering forward to prosper in the energy market as one of its future backbone technologies. For this to be successful, science, engineering, and process development as well as business and market development need to go hand in hand.}, issn = {0013-4651, 1945-7111}, doi = {10.1149/2.1441704jes}, url = {http://jes.ecsdl.org/content/164/4/F387}, author = {Ugljesa Babic and Michel Suermann and Felix N. B{\"u}chi and Lorenz Gubler and Thomas J. Schmidt} } @article {1030, title = {A Decade of Solid Oxide Electrolysis Improvements at DTU Energy}, journal = {ECS Transactions}, volume = {75}, year = {2017}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {3-14}, abstract = {Published on January 11th, 2017. Solid oxide electrolysis cells (SOECs) can efficiently convert electrical energy (e.g. surplus wind power) to energy stored in fuels such as hydrogen or other synthetic fuels. Performance and durability of the SOEC has increased orders of magnitudes within the last decade. This paper presents a short review of the R\&D work on SOEC single cells conducted at DTU Energy from 2005 to 2015. The SOEC improvements have involved increasing the of the oxygen electrode performance, elimination of impurities in the feed streams, optimization of processing routes, and fuel electrode structure optimization. All together, these improvements have led to a decrease in long-term degradation rate from ~40 \%/kh to ~0.4 \%/kh for steam electrolysis at -1 A/cm2, while the initial area specific resistance has been decreased from 0.44 Wcm2 to 0.15 Wcm2 at -0.5 A/cm2 and 750 {\textdegree}C.}, issn = {1938-6737, 1938-5862}, doi = {10.1149/07542.0003ecst}, url = {http://ecst.ecsdl.org/content/75/42/3}, author = {Anne Hauch and Karen Brodersen and Ming Chen and Christopher Graves and S{\o}ren H{\o}jgaard Jensen and Peter Stanley J{\o}rgensen and Peter Vang Hendriksen and Mogens Bjerg Mogensen and Simona Ovtar and Xiufu Sun} } @article {980, title = {Perovskite oxides {\textendash} a review on a versatile material class for solar-to-fuel conversion processes}, journal = {Journal of Materials Chemistry A}, volume = {5}, year = {2017}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {11983-12000}, issn = {2050-7488, 2050-7496}, doi = {10.1039/C7TA00987A}, url = {http://xlink.rsc.org/?DOI=C7TA00987A}, author = {Markus Kubicek and Alexander H. Bork and Jennifer L. M. Rupp} } @article {983, title = {Thermochemical CO 2 splitting using double perovskite-type Ba 2 Ca 0.66 Nb 1.34-x Fe x O 6-δ}, journal = {Journal of Materials Chemistry A}, volume = {5}, year = {2017}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {6874-6883}, issn = {2050-7488, 2050-7496}, doi = {10.1039/C6TA10285A}, url = {http://xlink.rsc.org/?DOI=C6TA10285A}, author = {Suresh Mulmi and Haomin Chen and Azfar Hassan and Jose F. Marco and Frank J. Berry and Farbod Sharif and Peter R. Slater and Edward P. L. Roberts and Stefan Adams and Venkataraman Thangadurai} } @inbook {749, title = {Application of SR methods for the study of nanocomposite materials for Hydrogen Energy}, volume = {84}, year = {2016}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {397-406}, publisher = {Elsevier Science Bv}, organization = {Elsevier Science Bv}, address = {Amsterdam}, abstract = {This work summarizes results of synchrotron radiation (SR) studies of the real/defect structure of nanocrystalline/nanocomposite oxide materials, which determines their functional properties in hydrogen energy field as catalysts and mixed ionic electronic conductors (cathodes and anodes of solid oxide fuel cells, oxygen separation membranes). For nanocrystalline ceria-zirconia mixed oxide prepared via modified Pechini route using ethanol solution of reagents, a high spatial uniformity of cations distribution between domains along with the oxygen sublattice deficiency revealed by full-profile Rietveld refinement of SR diffraction data provide structure disordering enhancing oxygen mobility. For PrNi0.5Co0.5O3-delta - Ce0.9Y0.1O2-delta nanocomposite extensive transfer of Pr cations into fluorite domains generates a new path of fast oxygen diffusion along chains of Pr3+ - Pr4+ cations as directly proved by analysis of the unit cell relaxation after changing pO(2) in perfect agreement with data obtained by oxygen isotope heteroexchange. (C) 2016 The Authors. Published by Elsevier B.V.}, author = {V. A. Sadykov and S. N. Pavlova and Z. S. Vinokurov and A. N. Shmakov and N. F. Eremeev and Yu E. Fedorova and E. P. Yakimchuk and V. V. Kriventsov and V. A. Bolotov and Yu Yu Tanashev and E. M. Sadovskaya and S. V. Cherepanova and K. V. Zolotarev and N. A. Vinokurov and B. A. Knyazev} } @conference {862, title = {Design and construction of a cascading pressure reactor prototype for solar-thermochemical hydrogen production}, volume = {1734}, year = {2016}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {120001}, address = {Cape Town, South Africa}, doi = {10.1063/1.4949203}, url = {http://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.4949203}, author = {Ivan Ermanoski and Johannes Grobbel and Abhishek Singh and Justin Lapp and Stefan Brendelberger and Martin Roeb and Christian Sattler and Josh Whaley and Anthony McDaniel and Nathan P. Siegel} } @article {1013, title = {Characterization of PEM fuel cell degradation by polarization change curves}, journal = {Journal of Power Sources}, volume = {294}, year = {2015}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {82-87}, abstract = {Published on October 30th, 2015. Polarization change curves, defined as a difference between the polarization curve at the beginning of life and the actual polarization curve after the cell has been operational for some time, were used to analyze degradation of a PEM fuel cell exposed to voltage cycling as an accelerated stress test for electrocatalyst degradation. Degradation, i.e., loss of voltage was due to increase of activation losses and increase of resistance in the catalyst layer, both most likely due to the loss of catalyst electrochemically active area. The results of the polarization change curves analysis correspond to the findings of the periodic individual tests performed during the accelerated stress test, such as electrochemical impedance spectroscopy, cyclic voltammetry and linear sweep voltammetry. Therefore, this method has potential to be used as a relatively quick and simple, yet effective, degradation diagnostic tool.}, issn = {0378-7753}, doi = {10.1016/j.jpowsour.2015.06.047}, url = {http://www.sciencedirect.com/science/article/pii/S0378775315010812}, author = {Dario Bezmalinovic and Boris Simic and Frano Barbir} } @article {806, title = {Concept analysis of an indirect particle-based redox process for solar-driven H2O/CO2 splitting}, journal = {Solar Energy}, volume = {113}, year = {2015}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {158-170}, abstract = {Published in March 2015.}, issn = {0038092X}, doi = {10.1016/j.solener.2014.12.035}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0038092X14006264}, author = {Stefan Brendelberger and Christian Sattler} } @article {951, title = {Design of a Solar Reactor to Split CO2 Via Isothermal Redox Cycling of Ceria}, journal = {Journal of Solar Energy Engineering}, volume = {137}, year = {2015}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {031007}, url = {https://solarenergyengineering.asmedigitalcollection.asme.org/article.aspx?articleID=1920469}, author = {Roman Bader and Rohini Bala Chandran and Luke J. Venstrom and Stephen J. Sedler and Peter T. Krenzke and Robert M. De Smith and Aayan Banerjee and Thomas R. Chase and Jane H. Davidson and Wojciech Lipi{\'L} and } } @article {946, title = {Perovskite La0.6Sr0.4Cr1-xCoxO3-δ solid solutions for solar-thermochemical fuel production: strategies to lower the operation temperature}, journal = {J. Mater. Chem. A}, volume = {3}, year = {2015}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {15546-15557}, issn = {2050-7488, 2050-7496}, doi = {10.1039/C5TA02519B}, url = {http://xlink.rsc.org/?DOI=C5TA02519B}, author = {A. H. Bork and M. Kubicek and M. Struzik and J. L. M. Rupp} } @article {860, title = {Surface controlled reduction kinetics of nominally undoped polycrystalline CeO 2}, journal = {Phys. Chem. Chem. Phys.}, volume = {17}, year = {2015}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {5849-5860}, issn = {1463-9076, 1463-9084}, doi = {10.1039/C4CP05742B}, url = {http://xlink.rsc.org/?DOI=C4CP05742B}, author = {Nicole Knoblauch and Lars D{\"o}rrer and Peter Fielitz and Martin Schm{\"u}cker and G{\"u}nter Borchardt} } @article {838, title = {Analysis and improvement of a high-efficiency solar cavity reactor design for a two-step thermochemical cycle for solar hydrogen production from water}, journal = {Solar Energy}, volume = {97}, year = {2013}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {26-38}, abstract = {Published in November 2013.}, issn = {0038092X}, doi = {10.1016/j.solener.2013.07.032}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0038092X13003071}, author = {Anis Houaijia and Christian Sattler and Martin Roeb and Matthias Lange and Stefan Breuer and Jan Peter S{\"a}ck} } @article {816, title = {Analytical Model of CeO 2 Oxidation and Reduction}, journal = {The Journal of Physical Chemistry C}, volume = {117}, year = {2013}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {24129-24137}, abstract = {Published on November 21st, 2013.}, issn = {1932-7447, 1932-7455}, doi = {10.1021/jp406578z}, url = {http://pubs.acs.org/doi/abs/10.1021/jp406578z}, author = {B. Bulfin and A. J. Lowe and K. A. Keogh and B. E. Murphy and O. L{\"u}bben and S. A. Krasnikov and I. V. Shvets} } @article {815, title = {Atomic layer deposited thin film metal oxides for fuel production in a solar cavity reactor}, journal = {International Journal of Hydrogen Energy}, volume = {37}, year = {2012}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {16888-16894}, abstract = {Published in November 2012.}, issn = {03603199}, doi = {10.1016/j.ijhydene.2012.08.004}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0360319912017703}, author = {Paul Lichty and Xinhua Liang and Christopher Muhich and Brian Evanko and Carl Bingham and Alan W. Weimer} } @article {835, title = {Low-temperature, manganese oxide-based, thermochemical water splitting cycle}, journal = {Proceedings of the National Academy of Sciences}, volume = {109}, year = {2012}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {9260{\textendash}9264}, url = {http://www.pnas.org/content/109/24/9260.short}, author = {Bingjun Xu and Yashodhan Bhawe and Mark E. Davis} } @article {1005, title = {Recommended Best Practices for the Characterization of Storage Properties of Hydrogen Storage Materials | Department of Energy}, year = {2012}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, url = {https://energy.gov/eere/fuelcells/downloads/recommended-best-practices-characterization-storage-properties-hydrogen-0}, author = {Karl J. Gross and K. Russell Carrington and Steven Barcelo} } @article {919, title = {Reimagining liquid transportation fuels : Sunshine to Petrol.}, number = {SAND2012-0307}, year = {2012}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, url = {http://www.osti.gov/servlets/purl/1035344/}, author = {James Edward Miller and Mark D. Allendorf and Andrea Ambrosini and Ken Shuang Chen and Eric Nicholas Coker and Daniel E. Dedrick and Richard B., Jr. Diver and Roy E., Jr. Hogan and Ivan Ermanoski and Terry Alan Johnson and Gary L. Kellog and Anthony H. McDaniel and Nathan Phillip Siegel and Chad Lynn Staiger and Ellen Beth Stechel} } @article {804, title = {Control of Heterogeneity in Nanostructured Ce1{\textendash}xZrxO2 Binary Oxides for Enhanced Thermal Stability and Water Splitting Activity}, journal = {The Journal of Physical Chemistry C}, volume = {115}, year = {2011}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {21022-21033}, abstract = {Published on November 3rd, 2011.}, issn = {1932-7447, 1932-7455}, doi = {10.1021/jp2071315}, url = {http://pubs.acs.org/doi/abs/10.1021/jp2071315}, author = {Nicholas D. Petkovich and Stephen G. Rudisill and Luke J. Venstrom and Daniel B. Boman and Jane H. Davidson and Andreas Stein} } @article {755, title = {The crystal structure of compositionally homogeneous mixed ceria-zirconia oxides by high resolution X-ray and neutron diffraction methods}, journal = {Open Chemistry}, volume = {15}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {438-445}, abstract = {The real/atomic structure of single phase homogeneous nanocrystalline Ce0.5Zr0.5O2 +/- delta oxides prepared by a modified Pechini route and Ni-loaded catalysts of methane dry reforming on their bases was studied by a combination of neutron diffraction, synchrotron X-ray diffraction, total X-ray scattering and X-ray absorption spectroscopy. The effects of sintering temperature and pretreatment in H-2 were elucidated. The structure of the mixed oxides corresponds to a tetragonal space group indicating a homogeneous distribution of Ce and Zr cations in the lattice. A pronounced disordering of the oxygen sublattice was revealed by neutron diffraction, supposedly due to incorporation of water into the structure when in contact with air promoted by the generation of anion vacancies in the lattice after reduction or calcination at high temperatures. However, such disordering has not resulted in any occupation of the oxygen interstitial positions in the bulk of the nanodomains.}, issn = {2391-5420}, doi = {10.1515/chem-2017-0044}, author = {Alexander N. Shmakov and Svetlana V. Cherepanova and Dmitrii A. Zyuzin and Yulia E. Fedorova and Ivan A. Bobrikov and Anne-Cecile Roger and Andrzej Adamski and Vladislav A. Sadykov} } @article {975, title = {Design of a pilot scale directly irradiated, high temperature, and low pressure moving particle cavity chamber for metal oxide reduction}, journal = {Solar Energy}, volume = {157}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {365-376}, issn = {0038092X}, doi = {10.1016/j.solener.2017.08.040}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0038092X17307181}, author = {Abhishek Singh and Justin Lapp and Johannes Grobbel and Stefan Brendelberger and Jan P. Reinhold and Lamark Olivera and Ivan Ermanoski and Nathan P. Siegel and Anthony McDaniel and Martin Roeb and Christian Sattler} } @article {854, title = {Design principles for metal oxide redox materials for solar-driven isothermal fuel production}, journal = {Advanced Energy Materials}, volume = {5}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {1401082}, issn = {16146832}, doi = {10.1002/aenm.201401082}, url = {http://doi.wiley.com/10.1002/aenm.201401082}, author = {Ronald Michalsky and Venkatesh Botu and Cory M. Hargus and Andrew A. Peterson and Aldo Steinfeld} } @article {918, title = {Development and Assessment of Solar-Thermal-Activated Fuel Production. Phase 1, Summary.}, number = {SAND2012-5658, 1055617}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, url = {http://www.osti.gov/servlets/purl/1055617/}, author = {James Edward Miller and Mark D. Allendorf and Andrea Ambrosini and Eric Nicholas Coker and Richard B., Jr. Diver and Ivan Ermanoski and Lindsey R. Evans and Roy E., Jr. Hogan and Anthony H. McDaniel} } @article {966, title = {Doped calcium manganites for advanced high-temperature thermochemical energy storage: Doped calcium manganites for thermochemical energy storage}, journal = {International Journal of Energy Research}, volume = {40}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {280-284}, issn = {0363907X}, doi = {10.1002/er.3467}, url = {http://doi.wiley.com/10.1002/er.3467}, author = {Sean M. Babiniec and Eric N. Coker and James E. Miller and Andrea Ambrosini} } @article {1020, title = {Durable Membrane Electrode Assemblies for Proton Exchange Membrane Electrolyzer Systems Operating at High Current Densities}, journal = {Electrochimica Acta}, volume = {210}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {502-511}, abstract = {High efficiencies, wide operation range and rapid response time have motivated the recent interest in proton exchange membrane (PEM) electrolysis for hydrogen generation with surplus electricity. However, degradation at high current densities and the associated mechanism has not been thoroughly explored so far. In this work, membrane electrode assemblies (MEA) from different suppliers are aged in a commercial PEM electrolyzer (2.5Nm3H2h--1), operating up to 4Acm--2 for more than 750h. In all cases, the cell voltage (Ecell) decreases during the testing period. Interestingly, the cells with Ir-black anodes exhibit the highest performance with the lowest precious metal loading (1mgcm-2). Electrochemical impedance spectroscopy (EIS) shows a progressive decrease in the specific exchange current, while the ohmic resistance decreases when doubling the nominal current density. This effect translates into an enhancement of cell efficiency at high current densities. However, Ir concurrently leaches out and diffuses into the membrane. No decrease in membrane thickness is observed at the end of the tests. High current densities do not lead to lowering the performance of the PEM electrolyzer over time, although MEA components degrade, in particular the anode.}, issn = {0013-4686}, doi = {10.1016/j.electacta.2016.04.164}, url = {http://www.sciencedirect.com/science/article/pii/S0013468616310167}, author = {P. Lettenmeier and R. Wang and R. Abouatallah and S. Helmly and T. Morawietz and R. Hiesgen and S. Kolb and F. Burggraf and J. Kallo and A. S. Gago and K. A. Friedrich} } @article {1027, title = {Electrochemical Hydrogen Compression: Efficient Pressurization Concept Derived from an Energetic Evaluation}, journal = {Journal of The Electrochemical Society}, volume = {164}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {F1187-F1195}, abstract = {Electrochemical hydrogen compression is a potentially high efficient, low-maintenance and silent technology to produce high pressure hydrogen. A new pressure concept with increased compression efficiency, termed intermediate differential pressure polymer electrolyte water electrolysis is proposed. With slightly pressurized oxygen and a much higher hydrogen pressure, this pressure concept profits from the advantages of the lower gas crossover of differential (only hydrogen compressed) pressure water electrolysis and the improved oxygen evolution reaction kinetics with increasing pressure of balanced pressure operation. Data for gas pressures up to 100 MPa is modeled, based on experimental results up to 5 MPa, of the three pressure concepts and validated with literature data up to 70 MPa. While differential pressure electrolyzer operation, following ideal isothermal compression, can be more efficient than today{\textquoteright}s best mechanical compressors up to 40 MPa, the intermediate pressure concept shows higher compression efficiency up to 90 MPa.}, issn = {0013-4651, 1945-7111}, doi = {10.1149/2.1361712jes}, url = {http://jes.ecsdl.org/content/164/12/F1187}, author = {Michel Suermann and Thomas Kiupel and Thomas J. Schmidt and Felix N. B{\"u}chi} } @article {1023, title = {Electrochemical investigation of electrocatalysts for the oxygen evolution reaction in PEM water electrolyzers}, journal = {International Journal of Hydrogen Energy}, volume = {33}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {4955-4961}, abstract = {To develop the proton exchange membrane water electrolyzer (PEMWE) with satisfactory performance and durability for application in a regenerative fuel cell (RFC) system, anode electrocatalysts of Ir, Ru and their oxides were prepared and incorporated into the catalyst coated membranes (CCM) of the PEMWE. Repetitive cyclic voltammetry of the Nafion bonded electrodes, steady state polarization curves and stability testing of the single PEMWE cells were performed to investigate the performance and stability of these electrocatalysts. The structure and specific surface areas of the electrocatalysts were characterized by XRD and BET. IrO2 exhibited a slightly lower performance but a markedly higher stability than the other electrocatalysts. By modifying the preparation process via a colloidal iridium hydroxide hydrate precursor, which permitted a lower heat treatment temperature, its performance was enhanced, corresponding to a terminal voltage of 1.63V at 1A/cm2.}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2008.06.039}, url = {http://www.sciencedirect.com/science/article/pii/S0360319908007520}, author = {Shidong Song and Huamin Zhang and Xiaoping Ma and Zhigang Shao and Richard T. Baker and Baolian Yi} } @article {765, title = {Electronic properties of crystalline materials observed in X-ray diffraction}, journal = {Physics Reports}, volume = {411}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {233-289}, issn = {03701573}, doi = {10.1016/j.physrep.2005.01.003}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0370157305000682}, author = {S Lovesey and E Balcar and K Knight and J Fernandezrodriguez} } @article {932, title = {Enhanced Oxidation Kinetics in Thermochemical Cycling of CeO 2 through Templated Porosity}, journal = {The Journal of Physical Chemistry C}, volume = {117}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {1692-1700}, issn = {1932-7447, 1932-7455}, doi = {10.1021/jp309247c}, url = {http://pubs.acs.org/doi/abs/10.1021/jp309247c}, author = {Stephen G. Rudisill and Luke J. Venstrom and Nicholas D. Petkovich and Tingting Quan and Nicholas Hein and Daniel B. Boman and Jane H. Davidson and Andreas Stein} } @article {1016, title = {Evaluation of nitrided titanium separator plates for proton exchange membrane electrolyzer cells}, journal = {Journal of Power Sources}, volume = {272}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {954-960}, abstract = {Proton exchanges membrane (PEM) regenerative fuel cell electrolysis of water is of great recent interest as a hydrogen generation technology. Anode side titanium current collectors and separator plates used in these applications typically employ coatings of platinum group metals to achieve durability and performance requirements in the high voltage, oxidizing environment. The present work assessed the potential for lower cost surface modified titanium by both thermal (gas) nitridation and plasma nitridation approaches. The nitrided Ti was found to result in far less hydrogen uptake in coupon testing than did Pt-plated Ti. Short-term (48~h) single-cell performance at 25~{\textdegree}C was approximately 13\% better (lower voltage) at 1.2~A~cm-2 for thermal and plasma nitrided plates vs. untreated Ti. However, at 50~{\textdegree}C and 1.5~A~cm-2, the thermally nitrided plate exhibited only on the order of 3\% better behavior (lower voltage) compared to the untreated Ti and plasma nitrided Ti. Durability testing for 500~h resulted in only a minor degradation in cell performance, on the order of 1{\textendash}2\% voltage increase, with the best behavior exhibited by the thermally nitrided Ti plate. Despite their relatively stable cell performance, extensive local oxidation of the thermally nitrided and plasma nitrided flow field regions was observed.}, issn = {0378-7753}, doi = {10.1016/j.jpowsour.2014.09.016}, url = {http://www.sciencedirect.com/science/article/pii/S0378775314014220}, author = {Todd J. Toops and Michael P. Brady and Feng-Yuan Zhang and Harry M. Meyer and Katherine Ayers and Andrew Roemer and Luke Dalton} } @article {971, title = {Experimental demonstration of the thermochemical reduction of ceria in a solar aerosol reactor}, journal = {Industrial \& Engineering Chemistry Research}, volume = {55}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {10618-10625}, issn = {0888-5885, 1520-5045}, doi = {10.1021/acs.iecr.6b02853}, url = {http://pubs.acs.org/doi/abs/10.1021/acs.iecr.6b02853}, author = {Michael Welte and Rafik Barhoumi and Adrian Zbinden and Jonathan R. Scheffe and Aldo Steinfeld} } @article {1015, title = {Failure of PEM water electrolysis cells: Case study involving anode dissolution and membrane thinning}, journal = {International Journal of Hydrogen Energy}, volume = {39}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {20440-20446}, abstract = {Polymer electrolyte membrane (PEM) water electrolysis is an efficient and environmental friendly method that can be used for the production of molecular hydrogen of electrolytic grade using zero-carbon power sources such as renewable and nuclear. However, market applications are asking for cost reduction and performances improvement. This can be achieved by increasing operating current density and lifetime of operation. Concerning performance, safety, reliability and durability issues, the membrane-electrode assembly (MEA) is the weakest cell component. Most performance losses and most accidents occurring during PEM water electrolysis are usually due to the MEA. The purpose of this communication is to report on some specific degradation mechanisms that have been identified as a potential source of performance loss and membrane failure. An accelerated degradation test has been performed on a MEA by applying galvanostatic pulses. Platinum has been used as electrocatalyst at both anode and cathode in order to accelerate degradation rate by maintaining higher cell voltage and higher anodic potential that otherwise would have occurred if conventional Ir/IrOx catalysts had been used. Experimental evidence of degradation mechanisms have been obtained by post-mortem analysis of the MEA using microscopy and chemical analysis. Details of these degradation processes are presented and discussed.}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2014.05.043}, url = {http://www.sciencedirect.com/science/article/pii/S0360319914013913}, author = {S. A. Grigoriev and K. A. Dzhus and D. G. Bessarabov and P. Millet} } @article {970, title = {High temperature hydrogen production: Design of a 750kW demonstration plant for a two-step thermochemical cycle}, journal = {Solar Energy}, volume = {135}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {232-241}, issn = {0038092X}, doi = {10.1016/j.solener.2016.05.059}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0038092X16301773}, author = {J.-P. S{\"a}ck and S. Breuer and P. Cotelli and A. Houaijia and M. Lange and M. Wullenkord and C. Spenke and M. Roeb and Chr. Sattler} } @article {995, title = {High-temperature sulfuric acid decomposition over complex metal oxide catalysts}, journal = {International Journal of Hydrogen Energy}, volume = {34}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {4065-4073}, abstract = {Activity and stability of FeTiO3, MnTiO3, NiFe2O4, CuFe2O4, NiCr2O4, 2CuO{\textperiodcentered}Cr2O3, CuO and Fe2O3 for the atmospheric decomposition of concentrated sulfuric acid in sulfur-based thermochemical water splitting cycles are presented. Catalyst activity was determined at temperatures from 725 to 900{\textdegree}C. Catalytic stability was examined at 850{\textdegree}C for up to 1 week of continuous operation. The results were compared to a 1.0wt\% Pt/TiO2 catalyst. Surface area by nitrogen physisorption, X-ray diffraction analyses, and temperature programmed desorption and oxidation were used to characterize fresh and spent catalyst samples. Over the temperature range, the catalyst activity of the complex oxides followed the general trend: 2CuO{\textperiodcentered}Cr2O3>CuFe2O4>NiCr2O4≈NiFe2O4>MnTiO3≈FeTiO3. At temperatures less than 800{\textdegree}C, the 1.0wt\% Pt/TiO2 catalyst had higher activity than the complex oxides, but at temperatures above 850{\textdegree}C, the 2CuO{\textperiodcentered}Cr2O3 and CuFe2O4 samples had the highest activity. Surface area was found to decrease for all of the metal oxides after exposure to reaction conditions. In addition, the two complex metal oxides that contained chromium were not stable in the reaction environment; both leached chromium into the acid stream and decomposed into their individual oxides. The FeTiO3 sample also produced a discoloration of the reactor due to minor leaching and converted to Fe2TiO5. Fe2O3, MnTiO3 and NiFe2O4 were relatively stable in the reaction environment. In addition, CuFe2O4 catalyst appeared relatively promising due to its high activity and lack of any leaching issues; however it deactivated in week-long stability experiments. Complex metal oxides may provide an attractive alternative to platinum-based catalyst for the decomposition of sulfuric acid; however, the materials examined in this study all displayed shortcomings including material sintering, phase changes, low activity at moderated temperatures due to sulfate formation, and decomposition to their individual oxides. More effort is needed in this area to discover metal oxide materials that are less expensive, more active and more stable than platinum catalysts.}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2008.09.064}, url = {http://www.sciencedirect.com/science/article/pii/S0360319908013062}, author = {Daniel M. Ginosar and Harry W. Rollins and Lucia M. Petkovic and Kyle C. Burch and Michael J. Rush} } @article {943, title = {Hydrogen production by water splitting on manganese ferrite-sodium carbonate mixture: Feasibility tests in a packed bed solar reactor-receiver}, journal = {International Journal of Hydrogen Energy}, volume = {39}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {20920-20929}, issn = {03603199}, doi = {10.1016/j.ijhydene.2014.10.105}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0360319914029450}, author = {Francesca Varsano and Maria Anna Murmura and Bruno Brunetti and Franco Padella and Aurelio La Barbera and Carlo Alvani and Maria Cristina Annesini} } @article {753, title = {In situ high-temperature powder diffraction studies of solid oxide electrolyte direct carbon fuel cell materials in the presence of brown coal}, journal = {Journal of Materials Science}, volume = {51}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {3928-3940}, abstract = {Direct carbon fuel cells are an attractive alternative for conventional power generation; however, there is almost no information on the stability of conventional fuel cell materials in direct carbon fuel cell environments, in particular when exposed to realistic fuels and the contaminants contained within these fuels. Similarly, there is little information on the structure and phase assemblage of solid fuels exposed to typical environments found in direct carbon fuel cells. In this paper, we use in situ high-resolution synchrotron powder diffraction on conventional high-temperature fuel cell materials and untreated brown coal to assess the stability and reactivity of these materials at various temperatures up to 850 {\textdegree}C. Materials investigated include nickel metal (Ni), gadolinium-doped ceria (GDC) and yttria-stabilised zirconia (YSZ). The phase stability, crystallite size, lattice parameters and associated linear coefficient of thermal expansion were determined. The phase stability of all fuel cell materials was found to be good with no additional phase formation noted either during heating or after prolonged periods at temperature. An increase in the crystallite size was observed for both GDC and Ni. Non-linear thermal expansion observed in these materials was related to partial reduction of cerium ions (GDC) and due to a Curie point transition (Ni). A wide range of mineral phases were observed in the coal samples and these phases were found to change significantly with temperature. Mineral phases consistent with the ash composition and existing literature on Victorian brown coal were assigned to phases observed.}, issn = {1573-4803}, doi = {10.1007/s10853-015-9712-7}, url = {https://doi.org/10.1007/s10853-015-9712-7}, author = {Adam C. Rady and C. Munnings and Sarbjit Giddey and Sukhvinder P. S. Badwal and Sankar Bhattacharya and Aniruddha Kulkarni} } @article {758, title = {Incommensurate Sinusoidal Oxygen Modulations in Layered Manganites La 1 - x Sr 1 + x MnO 4 ( x >= 0.5 )}, journal = {Physical Review Letters}, volume = {109}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, issn = {0031-9007, 1079-7114}, doi = {10.1103/PhysRevLett.109.107202}, url = {https://link.aps.org/doi/10.1103/PhysRevLett.109.107202}, author = {Joaqu{\'\i}n Garc{\'\i}a and Javier Herrero-Mart{\'\i}n and Gloria Sub{\'\i}as and Javier Blasco and J. S. Andreu and M. Concepci{\'o}n S{\'a}nchez} } @article {855, title = {Investigation of long term reactive stability of ceria for use in solar thermochemical cycles}, journal = {Energy}, volume = {89}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {924-931}, issn = {03605442}, doi = {10.1016/j.energy.2015.06.041}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0360544215007975}, author = {Nathan R. Rhodes and Michael M. Bobek and Kyle M. Allen and David W. Hahn} } @article {748, title = {Investigation of oxygen vacancies in CeO2/Pt system with synchrotron light techniques}, journal = {Journal of Physics: Conference Series}, volume = {712}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {012064}, issn = {1742-6596}, doi = {10.1088/1742-6596/712/1/012064}, url = {https://doi.org/10.1088\%2F1742-6596\%2F712\%2F1\%2F012064}, author = {L. Braglia and A. L. Bugaev and K. A. Lomachenko and A. V. Soldatov and C. Lamberti and A. A. Guda} } @article {843, title = {Investigation of perovskite structures as oxygen-exchange redox materials for hydrogen production from thermochemical two-step water-splitting cycles}, journal = {The Journal of Physical Chemistry C}, volume = {118}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {12682-12692}, issn = {1932-7447, 1932-7455}, doi = {10.1021/jp5034849}, url = {http://pubs.acs.org/doi/abs/10.1021/jp5034849}, author = {Antoine Demont and St{\'e}phane Abanades and Eric Beche} } @article {1022, title = {Long-time anodisation of titanium in sulphuric acid}, journal = {Surface and Coatings Technology}, volume = {202}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {1379-1384}, abstract = {The long-time behaviour of CP titanium in 1~M H2SO4 has been investigated. The authors revealed electrochemical behaviour during the long-time chrono-amperometric experiments. The ex-situ observations (EIS, ellipsometry, SEM and optical microscopy) brought out information concerning morphological changes of the surface as well as the change in the oxide thickness during the anodic oxidation process. From the obtained data, the authors developed a hypothesis describing the potentiostatic anodisation of titanium at voltages (up to 15~V) in 1~M H2SO4 with respect to time of anodisation.}, issn = {0257-8972}, doi = {10.1016/j.surfcoat.2007.06.027}, url = {http://www.sciencedirect.com/science/article/pii/S0257897207006676}, author = {D. Capek and M. -P. Gigandet and M. Masmoudi and M. Wery and O. Banakh} } @article {958, title = {Low-temperature reducibility of MxCe1{\textendash}xO2(M = Zr, Hf) under hydrogen atmosphere}, journal = {The Journal of Physical Chemistry C}, volume = {120}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {118-125}, issn = {1932-7447, 1932-7455}, doi = {10.1021/acs.jpcc.5b10796}, url = {http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.5b10796}, author = {Alexander Bonk and Arndt Remhof and Annika C. Maier and Matthias Trottmann and Meike V. F. Schlupp and Corsin Battaglia and Ulrich F. Vogt} } @article {1007, title = {Methods of photoelectrode characterization with high spatial and temporal resolution}, journal = {Energy \& Environmental Science}, volume = {8}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {2863-2885}, abstract = {Materials and photoelectrode architectures that are highly efficient, extremely stable, and made from low cost materials are required for commercially viable photoelectrochemical (PEC) water-splitting technology. A key challenge is the heterogeneous nature of real-world materials, which often possess spatial variation in their crystal structure, morphology, and/or composition at the nano-, micro-, or macro-scale. Different structures and compositions can have vastly different properties and can therefore strongly influence the overall performance of the photoelectrode through complex structure{\textendash}property relationships. A complete understanding of photoelectrode materials would also involve elucidation of processes such as carrier collection and electrochemical charge transfer that occur at very fast time scales. We present herein an overview of a broad suite of experimental and computational tools that can be used to define the structure{\textendash}property relationships of photoelectrode materials at small dimensions and on fast time scales. A major focus is on in situ scanning-probe measurement (SPM) techniques that possess the ability to measure differences in optical, electronic, catalytic, and physical properties with nano- or micro-scale spatial resolution. In situ ultrafast spectroscopic techniques, used to probe carrier dynamics involved with processes such as carrier generation, recombination, and interfacial charge transport, are also discussed. Complementing all of these experimental techniques are computational atomistic modeling tools, which can be invaluable for interpreting experimental results, aiding in materials discovery, and interrogating PEC processes at length and time scales not currently accessible by experiment. In addition to reviewing the basic capabilities of these experimental and computational techniques, we highlight key opportunities and limitations of applying these tools for the development of PEC materials.}, issn = {1754-5706}, doi = {10.1039/C5EE00835B}, url = {http://pubs.rsc.org/en/content/articlelanding/2015/ee/c5ee00835b}, author = {Daniel V. Esposito and Jason B. Baxter and Jimmy John and Nathan S. Lewis and Thomas P. Moffat and Tadashi Ogitsu and Glen D. O{\textquoteright}Neil and Tuan Anh Pham and A. Alec Talin and Jesus M. Velazquez and Brandon C. Wood} } @article {768, title = {M-edge x-ray absorption spectroscopy of 4f instabilities in rare-earth systems (invited)}, journal = {Journal of Applied Physics}, volume = {55}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {1910-1915}, issn = {0021-8979}, doi = {10.1063/1.333517}, url = {https://aip.scitation.org/doi/abs/10.1063/1.333517}, author = {G. Kaindl and G. Kalkowski and W. D. Brewer and B. Perscheid and F. Holtzberg} } @article {791, title = {Novel rare-earth-containing manganites Ba4REMn3O12 (RE=Ce, Pr) with 12R structure}, journal = {Journal of Solid State Chemistry}, volume = {177}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {714-720}, issn = {00224596}, doi = {10.1016/j.jssc.2003.08.025}, url = {http://linkinghub.elsevier.com/retrieve/pii/S002245960300505X}, author = {Antonio F Fuentes and Khalid Boulahya and Ulises Amador} } @article {967, title = {Oxidation and reduction reaction kinetics of mixed cerium zirconium oxides}, journal = {The Journal of Physical Chemistry C}, volume = {120}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {2027-2035}, issn = {1932-7447, 1932-7455}, doi = {10.1021/acs.jpcc.5b08729}, url = {http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.5b08729}, author = {B. Bulfin and F. Call and J. Vieten and M. Roeb and C. Sattler and I. V. Shvets} } @article {897, title = {Oxidation reaction kinetics for the steam-iron process in support of hydrogen production}, journal = {International Journal of Hydrogen Energy}, volume = {36}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {15125-15135}, issn = {03603199}, doi = {10.1016/j.ijhydene.2011.08.074}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0360319911019951}, author = {R.C. Stehle and M.M. Bobek and R. Hooper and D.W. Hahn} } @article {993, title = {Pt/TiO2 (rutile) catalysts for sulfuric acid decomposition in sulfur-based thermochemical water-splitting cycles}, journal = {Applied Catalysis A: General}, volume = {338}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {27-36}, abstract = {Thermochemical cycles consist of a series of chemical reactions to produce hydrogen from water at lower temperatures than by direct thermal decomposition. All the sulfur-based cycles for water splitting employ the sulfuric acid decomposition reaction. This work reports the studies performed on 1wt\% Pt/TiO2 (rutile) catalysts submitted to flowing concentrated sulfuric acid at 1123K and atmospheric pressure for different times on stream between 0 and 548h. Catalyst activity showed an initial decrease that lasted for about 66h, followed by a slight recovery of activity between 66 and 102h TOS, and a period of slower deactivation after 102h TOS. Catalyst sulfation did not seem to be detrimental to catalyst activity. The activity profile suggested that a complex dynamic situation, involving platinum sintering, volatilization, and oxidation, along with TiO2 morphological changes, affected catalyst activity in a non-monotonic way.}, issn = {0926-860X}, doi = {10.1016/j.apcata.2007.12.016}, url = {http://www.sciencedirect.com/science/article/pii/S0926860X07007363}, author = {L. M. Petkovic and D. M. Ginosar and H. W. Rollins and K. C. Burch and P. J. Pinhero and H. H. Farrell} } @article {756, title = {Rate Constants of Electrochemical Reactions in a Lithium-Sulfur Cell Determined by Operando X-ray Absorption Spectroscopy}, journal = {Journal of The Electrochemical Society}, volume = {165}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {A3487-A3495}, abstract = {The reduction of sulfur during discharge in a lithium-sulfur (Li-S) cell is known to occur in a series of reaction steps that involve lithium polysulfide intermediates. We present an operando study of the discharge of a solid-state Li-S cell using X-ray absorption spectroscopy (XAS). In theory, the average chain length of the polysulfides, xavg,cell, at a given depth of discharge is determined by the number of electrons delivered to the sulfur cathode. The dependence of xavg,cell measured by XAS on the depth of discharge is in excellent agreement with theoretical predictions. XAS is also used to track the formation of Li2S, the final discharge product, as a function of depth of discharge. The XAS measurements were used to estimate rate constants of a series of simple reactions commonly accepted in literature.}, issn = {0013-4651, 1945-7111}, doi = {10.1149/2.0981814jes}, url = {http://jes.ecsdl.org/content/165/14/A3487}, author = {Dunyang Rita Wang and Deep B. Shah and Jacqueline A. Maslyn and Whitney S. Loo and Kevin H. Wujcik and Erik J. Nelson and Matthew J. Latimer and Jun Feng and David Prendergast and Tod A. Pascal and Nitash P. Balsara} } @article {916, title = {Reactivity of doped ceria-based mixed oxides for solar thermochemical hydrogen generation via two-step water-splitting cycles}, journal = {Energy \& Fuels}, volume = {27}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {6068-6078}, issn = {0887-0624, 1520-5029}, doi = {10.1021/ef4014373}, url = {http://pubs.acs.org/doi/abs/10.1021/ef4014373}, author = {Alex Le Gal and St{\'e}phane Abanades and Nicolas Bion and Thierry Le Mercier and Virginie Harl{\'e}} } @article {987, title = {Redox thermodynamics and phase composition in the system SrFeO 3-δ {\textemdash} SrMnO 3-δ}, journal = {Solid State Ionics}, volume = {308}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {149-155}, issn = {01672738}, doi = {10.1016/j.ssi.2017.06.014}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0167273817302990}, author = {J. Vieten and B. Bulfin and M. Senholdt and M. Roeb and C. Sattler and M. Schm{\"u}cker} } @article {953, title = {The reduction and oxidation of ceria: A natural abundance triple oxygen isotope perspective}, journal = {Geochimica et Cosmochimica Acta}, volume = {159}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {220-230}, issn = {00167037}, doi = {10.1016/j.gca.2015.03.030}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0016703715001829}, author = {Justin Hayles and Huiming Bao} } @article {760, title = {Resonant 1 s {\textrightarrow} 3 d x-ray Bragg diffraction and structure factors for transition-metal compounds}, journal = {Physical Review B}, volume = {64}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, issn = {0163-1829, 1095-3795}, doi = {10.1103/PhysRevB.64.054405}, url = {https://link.aps.org/doi/10.1103/PhysRevB.64.054405}, author = {S. W. Lovesey and K. S. Knight and E. Balcar} } @article {771, title = {Resonant soft x-ray powder diffraction study to determine the orbital ordering in A-site-ordered SmBaMn 2 O 6}, journal = {Physical Review B}, volume = {77}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, issn = {1098-0121, 1550-235X}, doi = {10.1103/PhysRevB.77.060402}, url = {https://link.aps.org/doi/10.1103/PhysRevB.77.060402}, author = {M. Garc{\'\i}a-Fern{\'a}ndez and U. Staub and Y. Bodenthin and S. M. Lawrence and A. M. Mulders and C. E. Buckley and S. Weyeneth and E. Pomjakushina and K. Conder} } @article {968, title = {Solar thermochemical hydrogen production using ceria zirconia solid solutions: Efficiency analysis}, journal = {International Journal of Hydrogen Energy}, volume = {41}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {19320-19328}, issn = {03603199}, doi = {10.1016/j.ijhydene.2016.05.211}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0360319916307650}, author = {Brendan Bulfin and Matthias Lange and Lamark de Oliveira and Martin Roeb and Christian Sattler} } @article {937, title = {Spinel Metal Oxide-Alkali Carbonate-Based, Low-Temperature Thermochemical Cycles for Water Splitting and CO 2 Reduction}, journal = {Chemistry of Materials}, volume = {25}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {1564-1571}, issn = {0897-4756, 1520-5002}, doi = {10.1021/cm3038747}, url = {http://pubs.acs.org/doi/abs/10.1021/cm3038747}, author = {Bingjun Xu and Yashodhan Bhawe and Mark E. Davis} } @article {870, title = {Splitting CO2 with a ceria-based redox cycle in a solar-driven thermogravimetric analyzer}, journal = {AIChE Journal}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, issn = {00011541}, doi = {10.1002/aic.15501}, url = {http://doi.wiley.com/10.1002/aic.15501}, author = {M. Takacs and S. Ackermann and A. Bonk and M. Neises-von Puttkamer and Ph. Haueter and J. R. Scheffe and U. F. Vogt and A. Steinfeld} } @article {1024, title = {Sputtered iridium oxide films as electrocatalysts for water splitting via PEM electrolysis}, journal = {Electrochimica Acta}, volume = {52}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {3889-3894}, abstract = {Thin films of iridium oxide deposited by reactive magnetron sputtering have been investigated as catalysts for electrochemical water splitting in a polymer electrolyte membrane (PEM) cell. The sputtered films possess excellent mechanical stability and corrosion resistance at the high anodic potentials where oxygen evolution takes place. Their catalytic activity has been assessed using the conventional electrochemical methods of cyclovoltammetry and steady state polarisation techniques. A morphology factor assessing the catalyst active surface for a series of sputtered samples with varying thickness/loading has been determined and correlated to the catalytic efficiency. It has been proven that iridium oxide is a very efficient catalyst for oxygen evolution reaction (OER). The best performance with anodic current density of 0.3Acm-2 at potential of 1.55V (versus RHE) has shown the 500nm thick film containing 0.2mgcm-2 catalyst. The results obtained have also demonstrated the advantages of the reactive magnetron sputtering as simple and reliable method for deposition of efficient and cost effective catalysts for PEM electrolysis application.}, issn = {0013-4686}, doi = {10.1016/j.electacta.2006.11.005}, url = {http://www.sciencedirect.com/science/article/pii/S0013468606011571}, author = {E. Slavcheva and I. Radev and S. Bliznakov and G. Topalov and P. Andreev and E. Budevski} } @article {992, title = {Stability of supported platinum sulfuric acid decomposition catalysts for use in thermochemical water splitting cycles}, journal = {International Journal of Hydrogen Energy}, volume = {32}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {482-488}, abstract = {The activity and stability of several metal oxide supported platinum catalysts were explored for the sulfuric acid decomposition reaction. The acid decomposition reaction is common to several sulfur based thermochemical water splitting cycles. Reactions were carried out using a feed of concentrated liquid sulfuric acid (96wt\%) at atmospheric pressure at temperatures between 800 and 850oC and a weight hour space velocity of 52g acid/g catalyst/h. Reactions were run at high space velocities such that variations in kinetics were not masked by surplus catalyst. The influence of exposure to reaction conditions was explored for three catalysts; 0.1{\textendash}0.2wt\% Pt supported on alumina, zirconia and titania. The higher surface area Pt/Al2O3 and Pt/ZrO2 catalysts had the highest activity but deactivated rapidly. A low surface area Pt/TiO2 catalyst had good stability in short term tests, but slowly lost activity for over 200h of continuous operation.}, issn = {0360-3199}, doi = {10.1016/j.ijhydene.2006.06.053}, url = {http://www.sciencedirect.com/science/article/pii/S0360319906002655}, author = {Daniel M. Ginosar and Lucia M. Petkovic and Anne W. Glenn and Kyle C. Burch} } @article {747, title = {Structural Features of Sm- and Gd-Doped Ceria Studied by Synchrotron X-ray Diffraction and μ-Raman Spectroscopy}, journal = {Inorganic Chemistry}, volume = {54}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {4126-4137}, abstract = {A structural study of Sm- and Gd-doped ceria was performed with the aim to clarify some unexplained structural features. (Ce1{\textendash}xREx)O2{\textendash}x/2 samples (RE = Sm, Gd; x = 0, 0.1, ..., 1) were prepared by coprecipitation of mixed oxalates and subsequent thermal treatment at 1473, 1173, or 1073 K in air; they were then analyzed at room temperature both by synchrotron X-ray diffraction and μ-Raman spectroscopy. Two structural models were adopted to fit the experimental data, namely, a fluoritic one, resembling the CeO2 structure at low RE content, and a hybrid one at higher RE content, intermediate between the CeO2 and the RE2O3 structures. Two main transitions were detected along the compositional range: (a) an RE-dependent transition at the boundary between the fluoritic and the hybrid regions, of a chemical nature; (b) an RE-independent transition within the hybrid region at \~{}0.5, having a purely geometrical nature. The presence of two finely interlaced F- and C-based structures within the hybrid region was confirmed, and hints of their composition were obtained by μ-Raman spectroscopy. The obtained results indicate a possible explanation for the non-Vegard behavioral trend of the cell parameters.}, issn = {0020-1669}, doi = {10.1021/acs.inorgchem.5b00395}, url = {https://doi.org/10.1021/acs.inorgchem.5b00395}, author = {Cristina Artini and Marcella Pani and Maria Maddalena Carnasciali and Maria Teresa Buscaglia and Jasper Rikkert Plaisier and Giorgio Andrea Costa} } @article {752, title = {On the structural stability of crystalline ceria phases in undoped and acceptor-doped ceria materials under in situ reduction conditions}, journal = {Crystengcomm}, volume = {21}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {145-154}, abstract = {The reduction of pure and Sm-doped ceria in hydrogen has been studied by synchrotron-based in situ X-ray diffraction to eventually prove or disprove the presence of crystalline cerium hydride (CeHx) phases and the succession of potential structural phase (trans)formations of reduced cerium oxide phases during heating-cooling cycles up to 1273 K. Despite a recent report on the existence of bulk and surface CeHx phases during reductive treatment of pure CeO2 in H-2, structural analysis by Rietveld refinement as well as additional H-1-NMR spectroscopy did not reveal the presence of any crystalline CeHx phase. Rather, a sequence of phase transformations during the re-cooling process in H-2 has been observed. In both samples, the reduced/defective fluorite lattice undergoes at first a transformation into a bixbyite-type lattice with a formal stoichiometry Ce0.583+Ce0.424+O1.71 and Sm0.153+Ce0.393+Ce0.464+O1.73, before a transformation into rhombohedral Ce7O12 takes place in pure CeO2. This phase is clearly absent for the Sm-doped material. Finally, a triclinic Ce11O20 phase appears for both materials, which can be recovered to room temperature, and on which a phase mixture of bixbyite Ce0.663+Ce0.344+O1.67, rh-Ce0.603+Ce0.404+O1.70 and tri-Ce0.483+Ce0.524+O1.76 (for pure CeO2) or bixbyite Sm0.153+Ce0.473+Ce0.384+O1.69 and tri-Sm0.153+Ce0.313+Ce0.544+O1.77 (for Sm-doped CeO2) prevails. The absence of the rhombohedral phase indicates that Sm doping leads to the stabilization of the bixbyite phase over the rhombohedral one at this particular oxygen vacancy concentration. It is worth noting that recent work proves that hydrogen is indeed incorporated within the structures during the heat treatments, but under the chosen experimental conditions it has apparently no effect on the salient structural principles during reduction.}, issn = {1466-8033}, doi = {10.1039/c8ce01726c}, author = {Maged F. Bekheet and Matthias Gruenbacher and Lukas Schlicker and Albert Gili and Andrew Doran and Jan Dirk Epping and Aleksander Gurlo and Bernhard Kloetzer and Simon Penner} } @article {780, title = {Surface Defect Chemistry and Electronic Structure of Pr 0.1 Ce 0.9 O 2-δ Revealed in Operando}, journal = {Chemistry of Materials}, volume = {30}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {2600-2606}, issn = {0897-4756, 1520-5002}, doi = {10.1021/acs.chemmater.7b05129}, url = {http://pubs.acs.org/doi/10.1021/acs.chemmater.7b05129}, author = {Qiyang Lu and Gulin Vardar and Maximilian Jansen and Sean R. Bishop and Iradwikanari Waluyo and Harry L. Tuller and Bilge Yildiz} } @article {923, title = {Thermodynamic analysis of isothermal redox cycling of ceria for solar fuel production}, journal = {Energy \& Fuels}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {130812072357003}, issn = {0887-0624, 1520-5029}, doi = {10.1021/ef400132d}, url = {http://pubs.acs.org/doi/abs/10.1021/ef400132d}, author = {Roman Bader and Luke J. Venstrom and Jane H. Davidson and Wojciech Lipi{\'n}ski} } @article {972, title = {Thermodynamic assessment of an electrically-enhanced thermochemical hydrogen production (EETHP) concept for renewable hydrogen generation}, journal = {International Journal of Hydrogen Energy}, volume = {42}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {14380-14389}, issn = {03603199}, doi = {10.1016/j.ijhydene.2017.04.125}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0360319917315331}, author = {Sean M. Babiniec and Andrea Ambrosini and James E. Miller} } @article {947, title = {Thermodynamics of CeO2 thermochemical fuel production}, journal = {Energy \& Fuels}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {150126104600001}, issn = {0887-0624, 1520-5029}, doi = {10.1021/ef5019912}, url = {http://pubs.acs.org/doi/abs/10.1021/ef5019912}, author = {B. Bulfin and F. Call and M. Lange and O. L{\"u}bben and C. Sattler and R. Pitz-Paal and I. V. Shvets} } @article {834, title = {Understanding Chemical Expansion in Non-Stoichiometric Oxides: Ceria and Zirconia Case Studies}, journal = {Advanced Functional Materials}, volume = {22}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {1958-1965}, issn = {1616301X}, doi = {10.1002/adfm.201102648}, url = {http://doi.wiley.com/10.1002/adfm.201102648}, author = {Dario Marrocchelli and Sean R. Bishop and Harry L. Tuller and Bilge Yildiz} } @article {1031, title = {Understanding the Current-Voltage Behavior of High Temperature Solid Oxide Fuel Cell Stacks}, journal = {Journal of The Electrochemical Society}, volume = {164}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {F1460-F1470}, abstract = {High temperature solid oxide fuel cell (SOFC) stacks are highly efficient and environmentally friendly electrochemical systems, which convert the chemical energy of fuel gases with oxygen from air directly into electrical energy. During operation of SOFC stacks under system operating conditions pronounced temperature and fuel gas composition gradients along the cell area and along the height of the stack occur. Therefore, in contrast to SOFC cells, the electrochemical behavior of SOFC stacks is much more complex and has not sufficiently been studied. Specially, a shortcoming exists in terms of understanding the homogeneity, performance loss mechanisms, and various resistances and overvoltages within the stack repeat components. Therefore, this paper focuses on the improvement of the understanding and of the interpretation of different current-voltage curves of solid oxide fuel cell stack repeat units. Three different cases are discussed: repeat units with high power performance, with high cell contact resistance and with high fuel utilization. The stacks were investigated by current-voltage curves, electrochemical impedance spectroscopy and gas analysis. In order to understand the electrochemical behavior of these three cases both experimental and modeling results are presented, compared and discussed.}, issn = {0013-4651, 1945-7111}, doi = {10.1149/2.1541713jes}, url = {http://jes.ecsdl.org/content/164/13/F1460}, author = {M. Lang and C. Bohn and M. Henke and G. Schiller and C. Willich and F. Hauler} } @article {787, title = {Understanding the spectroscopic signatures of Mn valence changes in the valence energy loss spectra of Li-Mn-Ni-O spinel oxides}, journal = {Physical Review Materials}, volume = {1}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, issn = {2475-9953}, doi = {10.1103/PhysRevMaterials.1.074402}, url = {https://link.aps.org/doi/10.1103/PhysRevMaterials.1.074402}, author = {M. K. Kinyanjui and P. Axmann and M. Mancini and G. Gabrielli and P. Balasubramanian and F. Boucher and M. Wohlfahrt-Mehrens and U. Kaiser} } @article {973, title = {Vacuum pumping options for application in solar thermochemical redox cycles {\textendash} Assessment of mechanical-, jet- and thermochemical pumping systems}, journal = {Solar Energy}, volume = {141}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {91-102}, issn = {0038092X}, doi = {10.1016/j.solener.2016.11.023}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0038092X16305552}, author = {Stefan Brendelberger and Henrik von Storch and Brendan Bulfin and Christian Sattler} } @article {774, title = {Valence measurement of Mn oxides using Mn K-beta emission spectroscopy}, journal = {JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS}, volume = {61}, note = {{\textquoteright}doi: 10.1021/acsenergylett.0c01132\n - I.Am.Hydrogen{\textquoteright} {\textquoteright}\n - jyoungstrom{\textquoteright} {\textquoteright}Jason thinks this is great.\n~\n - jyoungstrom{\textquoteright} {\textquoteright}\n - estechel{\textquoteright} }, pages = {547-460}, abstract = {High resolution Mn K-beta emission spectra provide a direct method to probe the effective spin state and charge density on Mn sites. Direct comparison of MnF2 and MnO reveals significant changes due to the degree of covalency. The detailed shape and energy shi of thr spectra for the perovskite LaMnO3 and CaMnO3 compounds are found to be very similar to Mn2O3 and MnO2, respectively. Detailed Mn K-beta X-ray emission results on La1-xCaxMnO3 can be well fit by linear superpositions of the end member spectra. However, for x < 0.3, a retarded response is found. No evidence for Mn2+ is found}, author = {Q Qian and TA Tyson and CC Kao and JP Rueff and FMF deGroot and M Croft and SW Cheong and M Breenblatt and MA Subramanian} }