Highly sulfur poisoning-tolerant BaCeO3-impregnated La0.6Sr0.4Co0.2Fe0.8O3-δ cathodes for solid oxide fuel cells

Electrochemical performance and sulfur (SO2) tolerance were studied on pristine La0.6Sr0.4Co0.2Fe0.8O3-delta (LSCF) and BaCeO3-impregnated LSCF (BaCeO3-LSCF) composite cathodes of solid oxide fuel cells (SOFCs). Compared to pristine LSCF electrodes, BaCeO3-LSCF composite electrodes exhibited reduced electrode polarization resistance and significantly lower activation energy for the O-2 reduction reaction, indicating that BaCeO2 impregnation is effective at promoting the electrocatalytic activity of LSCF electrodes at low temperatures. Most significantly, BaCeO3-LSCF cathodes show remarkable tolerance and resistance towards sulfur via the formation of BaSO4 instead of SrSO4 on the electrode surface, preventing excess Sr deficiency at the A-site of LSCF perovskite and thus mitigating the sulfur poisoning effect. BaCeO3-LSCF cathodes show potential as highly active and excellent anti-sulfur oxygen electrodes for SOFCs.