Enhanced Chromium Tolerance of La0.6Sr0.4Co0.2Fe0.8O3-δ Cathode by BaO Infiltration

Abstract

Performance degradation of cathodes due to the attack by chromium from Fe-Cr alloy interconnect is a major barrier to develop long-term durable solid oxide fuel cells (SOFCs). In this presentation, we report the development of a chromium tolerant BaO infiltrated La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathode. After the test at 800oC for 100 h in the presence of Fe-Cr interconnect, the electrode polarization resistance (RE) of the infiltrated BaO-LSCF electrode increases by 0.05 Ω cm2, much smaller than 0.48 Ω cm2 in the case of the LSCF electrode. The presence of BaO nanoparticles inhibits the formation of SrCrO4 by forming thermodynamically stable and conducive BaCrO4, thus preventing the extraction of Sr at the A-site of LSCF perovskite structure and mitigating the poisoning effect of Cr on the electrocatalytic activity of LSCF. The results have demonstrated a new and effective strategy to develop highly tolerant and resistant cathodes towards the Cr contaminant of SOFCs.