A high-performance solid oxide fuel cell anode based on lanthanum strontium vanadate

Ceramic composites were prepared by infiltration of La0.7Sr0.3VO3.85 (LSV) into porous scaffolds of yttria-stabilized zirconia (YSZ) and tested for use as solid oxide fuel cell (SOFC) anodes. There was no evidence for solid-state reaction between LSV and YSZ at calcination temperatures up to 1273 K. For calcination at 973 K, LSV formed a continuous film over the YSZ. The LSV phase reduced easily upon heating in H2 to 973 K, with the reduction forming pores in the LSV and greatly increasing its surface area. The electrodes showed high electronic conductivity after reduction, with a 10-vol% LSV–YSZ composite exhibiting a conductivity of 2 S cm−1 at 973 K. In the absence of an added catalyst, the LSV–YSZ electrodes showed relatively poor performance; however, an electrode impedance of approximately 0.1 Ω cm2 was achieved at 973 K in humidified H2 following addition of 0.5 vol% Pd and 2.8 vol% ceria The LSV–YSZ composites were stable in CH4 but there was evidence for poisoning of the Pd catalyst by V following high-temperature oxidation.

► Composite anode was prepared by infiltration of La0.7Sr0.3VO3.85 into porous YSZ. ► This anode has a sufficiently high electronic conductivity and reduces easily. ► The addition of a Pd/ceria catalyst decreases electrode impedances in both H2 and CH4 fuels.