Mechanism and kinetics of Ni-Y2O3-ZrO2 hydrogen electrode for water electrolysis reactions in solid oxide electrolysis cells
MetadataShow full item record
© The Author(s) 2015. Published by ECS. Ni-Y2O3 stabilized ZrO2 (Ni-YSZ) cermet is the most commonly used hydrogen electrode for hydrogen oxidation reaction (HOR) under solid oxide fuel cell (SOFC) mode and water reduction reaction (WRR) under solid oxide electrolysis cell (SOEC) mode. Here we studied the electrocatalytic activity of Ni-YSZ electrodes as a function of Ni content, water concentration and dc bias for WRR and HOR under SOEC and SOFC modes, respectively. The activity of Ni-YSZ cermet increases significantly with the increase of YSZ content due to the enhanced three phase boundaries (TPB). The electrode activity for the WRR and in less degree for the HOR increases with the increase of steam concentration. The electrode polarization resistance, RE, for the WRR increases with the dc bias, while in the case of HOR, RE decreases with the dc bias, demonstrating that kinetically the WRR and HOR is not reversible on the Ni-YSZ cermet electrodes under SOFC and SOEC operation modes. The WRR can be described by two electrode processes associated with the H2O adsorption and diffusion on the oxygen-covered Ni or YSZ surface in the vicinities of TPB, followed by the charge transfer. The significant increase of high frequency electrode polarization resistance, RH and in much less extent low frequency electrode polarization resistance, RL with the dc bias indicates that the water electrolysis reaction is kinetically controlled by the reactant supply (e.g., the adsorbed H2O species) limited charge transfer process.
This open access article is distributed under the Creative Commons license https://creativecommons.org/licenses/by/4.0/
Showing items related by title, author, creator and subject.
Electrochemical Characterization of Ni/Y2O3-ZrO2 Hydrogen Electrode for Water Splitting in Solid Oxide Electrolysis CellsPan, W.; Chen, K.; Ai, N.; Lü, Z.; Jiang, San Ping (2015)Ni/Y2O3 stabilized ZrO2 (Ni/YSZ) cermet is a widely used hydrogen electrode for solid oxide fuel cells (SOECs), but detailed studies regarding the water splitting processes are scarce. Here we report the preliminary results ...
Highly active and stable Er<inf>0.4</inf>Bi<inf>1.6</inf>O<inf>3</inf> decorated La<inf>0.76</inf>Sr<inf>0.19</inf>MnO<inf>3+: d</inf> nanostructured oxygen electrodes for reversible solid oxide cellsAi, N.; Li, N.; He, S.; Cheng, Y.; Saunders, M.; Chen, K.; Zhang, T.; Jiang, San Ping (2017)© 2017 The Royal Society of Chemistry. Bismuth based oxides have excellent ionic conductivity and fast oxygen surface kinetics and show promising potential as highly active electrode materials in solid oxide cells (SOCs) ...
Novel solid oxide cells with SrCo0.8Fe0.1Ga0.1O3-d oxygen electrode for flexible power generation and hydrogen productionMeng, X.; Shen, Y.; Xie, M.; Yin, Y.; Yang, N.; Ma, Z.; Diniz Da Costa, J.; Liu, Shaomin (2016)This work investigates the performance of solid oxide cells as fuel cells (SOFCs) for power production and also as electrolysis cells (SOECs) for hydrogen production. In order to deliver this dual mode flexible operation ...