Analysis of the Anode Reaction of Solid Oxide Electrolyzer Cells with BaZr0.4Ce0.4Y0.2O3-delta Electrolytes and Sm0.5Sr0.5CoO3-delta Anodes

作者：Kobayashi Taisei; Kuroda Kosuke; Jeong SeongWoo; Kwon Hyuna; Zhu Chunyu; Habazaki Hiroki; Aoki Yoshitaka

来源：Journal of the Electrochemical Society, 2018, 165(5): F342-F349.

DOI：10.1149/2.0891805jes

Anodic reaction pathways in proton-conducting solid oxide electrolyzer cells (H+ -SOECs) were investigated using electrochemical impedance spectroscopy with a cell structure of Sm0.5Sr0.5CoO3 (anode) vertical bar BaZr0.4Ce0.4Y0.2O3-delta vertical bar Pt (cathode). Densely sintered BaZr0.4Ce0.4Y0.2O3-delta ceramics (>97% relative density) were fabricated by a reactive sintering process with a 2 mol% Zn(NO3)(2) additive and were applied as the electrolyte. The impedance spectra were measured while the oxygen (p(O2)) and water partial pressures (p(H2O)) in the anode side were systematically varied, which revealed that the SOECs have two polarization resistances at the anode side, one proportional to p(O2)(-1/4) and p(H2O)(0) and another insensitive to p(O2) and p(H2O). A comparison between the experimental results and elementary step modeling revealed that the actual anode reactions could be described by the reverse mode H+-SOFC cathode reactions, and, thus, the elementary steps dominating the anodic polarization resistance were assigned.

• 出版日期2018