Electrochemical performance of Sr1.9La0.1Fe1.5Mo0.5O6-d symmetric electrode for solid oxide fuel cells with carbon-based fuels

La-doped Sr2-xLaxFe1.5Mo0.5O6-$ perovskite oxides are synthesized and used as a symmetric electrode to evaluate the effect of La on the crystal structure, conductivity, and catalytic activity for O2 reduction and H2 oxidation reaction. The electronic doping effect dominates the oversize effect in Sr2-xLaxFe1.5Mo0.5O6-$ oxide, resulting in unit cell volume expansion and decreased conductivity in air. In addition, the introduction of La increases the chemical structural stability of Sr2Fe1.5Mo0.5O6-$ in reducing condition due to the higher La -O bond compared with Sr-O bond, leading to high catalytic activity for the H2 oxidation reaction. At 800 degrees C, the Rp values of Sr1.9La0.1Fe1.5Mo0.5O6-$ symmetric cell in air and wet H2 are as low as 0.075 and 0.21 U cm2, respectively. Moreover, the peak power densities of 769, 561, 439, and 653 mW cm-2 at 850 degrees C are obtained when wet H2, CO, CH4, and C3H8 are used as fuels on Sr1.9La0.1Fe1.5Mo0.5O6-$/LSGM/Sr1.9La0.1Fe1.5Mo0.5O6-$ cell. The symmetric cell also shows excellent stability (>100 h) in wet H2/air, implying Sr1.9La0.1Fe1.5Mo0.5O6-8 oxide is a promising symmetric electrode material. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

La-doped Sr2-xLaxFe1.5Mo0.5O6-$ perovskite oxides exhibit improved crystal structure stability and catalytic activity in a symmetric electrode, showing promising potential for various applications.