@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 {1142, title = {Intermediate Temperature Solid Oxide Cell with a Barrier Layer Free Oxygen Electrode and Phase Inversion Derived Hydrogen Electrode}, journal = {Journal of the Electrochemical Society}, volume = {169}, year = {2022}, month = {3}, keywords = {area specific resistance, cathode, electrical conductivity, intermediate temperature-operating solid oxide fuel cell, layered perovskite}, doi = {10.1149/1945-7111/ac565a}, author = {Zhang, Yongliang and Xu, Nansheng and Tang, Qiming and Huang, Kevin} } @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 {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 {1160, title = {Modeling Electrokinetics of Oxygen Electrodes in Solid Oxide Electrolyzer Cells}, journal = {Journal of The Electrochemical Society}, volume = {168}, year = {2021}, month = {11/2021}, pages = {114510}, abstract = {A microscale model is presented in this study to simulate electrode kinetics of the oxygen electrode in a solid oxide electrolyzer cell (SOEC). Two mixed ionic/electronic conducting structures are examined for the oxygen producing electrode in this work: single layer porous lanthanum strontium cobalt ferrite (LSCF), and bilayer LSCF/SCT (strontium cobalt tantalum oxide) structures. A yttrium-stabilized zirconia (YSZ) electrolyte separates the hydrogen and oxygen electrodes, as well as a gadolinium doped-ceria (GDC) buffer layer on the oxygen electrode side. Electrochemical reactions occurring at the two-phase boundaries (2PBs) and three-phase boundaries (3PBs) of single-layer LSCF and bilayer LSCF/SCT oxygen electrodes are modeled under various SOEC voltages with lattice oxygen stoichiometry as the key output. The results reveal that there exists a competition in electrode kinetics between 2PBs and 3PBs, but 3PBs are the primary reactive sites for single-layer LSCF oxygen electrode under high voltages. These locations experience the greatest oxygen stoichiometry variations and are therefore the most likely locations for dimensional changes. By applying an active SCT layer over LSCF, the 2PBs become activated to compete with the 3PBs, thus alleviating oxygen stoichiometry variations and reducing the likelihood of dimensional change. This strategy could reduce lattice structural expansion, proving to be valuable for electrode-electrolyte delamination prevention and will be the focus of future work.}, keywords = {Barium zirconate, Defect transport, electrode-electrolyte delamination prevention, Faradaic efficiency, lattice oxygen stoichiometry, microscale model, o-SOEC, oxygen electrode, solid oxide electrolyzer cell}, doi = {10.1149/1945-7111/ac35fc}, url = {https://doi.org/10.1149/1945-7111/ac35fc}, author = {Korey Cook and Jacob Wrubel and Zhiwen Ma and Kevin Huang and Xinfang Jin} } @article {1127, title = {CeTi2O6{\textemdash}A Promising Oxide for Solar Thermochemical Hydrogen Production}, journal = {ACS Applied Materials \& Interfaces}, volume = {12}, year = {2020}, pages = {21521-21527}, keywords = {brannerite structure, Cerium based oxides, CeTi2O6, high thermal stability, large entropy of reduction, small reduction enthalpy}, doi = {CeTi2O6{\textemdash}A Promising Oxide for Solar Thermochemical Hydrogen Production}, author = {S. S. Naghavi and J. He and C. Wolverton} } @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 {1191, title = {Progress in Metal-Supported Solid Oxide Fuel Cells and Electrolyzers with Symmetric Metal Supports and Infiltrated Electrodes}, journal = {ECS Transactions}, volume = {91}, year = {2019}, month = {07/2019}, pages = {877{\textendash}885}, abstract = {The LBNL metal-supported solid oxide cell architecture contains zirconia electrolyte and porous backbones co-sintered between porous stainless steel supports. Advantages of this design include low-cost structural materials, mechanical ruggedness, excellent tolerance to redox cycling, and extremely fast start-up capability. With infiltrated catalysts, high performance is also achieved: 1.5 W/cm2 with hydrogen fuel and 1.3 W/cm2 with internal reforming of ethanol fuel at 700 {\textdegree}C; 2.6 A/cm2 electrolysis current density at 1.3V and 50\% steam/50\% hydrogen at 700{\textdegree}C. Recent approaches to mitigating catalyst coarsening and Cr deposition within the cathode stabilize the microstructure during operation. The degradation rate is improved to 2.3\% kh-1 at 700{\textdegree}C in fuel cell mode. Electrolysis operation, however, results in higher degradation rate. Preliminary effort to fabricate metal-supported cells with proton conducting electrolyte is successful for La0.99Ca0.01NbO4 electrolyte, and specific challenges for BaZr0.7Ce0.2Y0.1O3-δ electrolyte are determined.}, keywords = {BaZr0.7Ce0.2Y0.1O3-δ electrolyte, HTE, La0.99Ca0.01NbO4 electrolyte, SOEC}, doi = {10.1149/09101.0877ecst}, url = {https://doi.org/10.1149/09101.0877ecst}, author = {Emir Dogdibegovic and Fengyu Shen and Ruofan Wang and Ian Robinson and Grace Y Lau and Michael C Tucker} } @article {1193, title = {Synergistic Coupling of Proton Conductors BaZr0.1Ce0.7Y0.1Yb0.1O3-δ and La2Ce2O7 to Create Chemical Stable, Interface Active Electrolyte for Steam Electrolysis Cells}, journal = {ACS Applied Materials \& Interfaces}, volume = {11}, year = {2019}, pages = {18323-18330}, keywords = {BaZr0.1Ce0.7Y0.1Yb0.1O3-δ, durability, HTE, La2Ce2O7, Protonic ceramic electrolysis cell, SOEC}, doi = {10.1021/acsami.9b00303}, url = {https://doi.org/10.1021/acsami.9b00303}, author = {Li, Wenyuan and Guan, Bo and Ma, Liang and Tian, Hanchen and Liu, Xingbo} }