Engineering composite oxide SOFC anodes for efficient oxidation of methane

Abstract

Ceramic anodes for solid oxide fuel cells (SOFCs) were prepared by aqueous impregnation of nitrate salts to produce composites with 45 wt % La0.8 Sr0.2 Cr0.5 Mn0.5 O3 (LSCM) in a 65% porous yttria-stabilized zirconia (YSZ) scaffold. Scanning electron micrographs indicate that the LSCM coats the YSZ pores following calcination at 1473 K. Composites produced in this manner exhibit conductivities at 1073 K of approximately 1 Scm in air and 0.1 Scm in humidified H2. A SOFC with a composite anode composed of 45 wt % LSCM, 0.5 wt % Pd, and 5 wt % ceria exhibited maximum power densities at 1073 K of 1.1 and 0.71 W cm-2 in humidified (3% H2 O) H2 and methane, respectively. © 2007 The Electrochemical Society.