@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 {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}
}
