Superior electrochemical performance of non-precious Co-Ni-Mo alloy catalyst-impregnated Sr2FeMoO6-δ as an electrode material for symmetric solid oxide fuel cells

Abstract

Double perovskite-based Sr2FeMoO6-δ (SFM), as an electrode material for symmetric solid oxide fuel cells (SOFCs), has been synthesized by a sucrose-modified combustion technique. SFM showed metallic conducting behavior with a conductivity of 215.72Scm−1 in dry H2 at 800°C. The polarization resistance (Rp) for H2 oxidation, evaluated using half-cell symmetry, was recorded as 0.192Ωcm2 under humidified H2 at 800°C. Improved catalytic activity was accomplished by impregnation of Pd or Co-Ni-Mo (0.1:5:1 molar ratio, CNM) via a glycine-mediated impregnation technique. The Rp values for the Pd- and CNM-impregnated SFM were 0.087 and 0.060Ωcm2, respectively, under humidified H2 at 800°C. The symmetric SOFC with an La0.8Sr0.2Ga0.8Mg0.2O3-δ (LSGM) electrolyte and a CNM-impregnated SFM electrode showed maximum power densities of 1066mWcm−2 and 480mWcm−2 at 800°C under humidified H2 and CH4, respectively.