Tailoring cobalt‐free La_0.5Sr_0.5FeO_3‐δ cathode with a nonmetal cation‐doping strategy for high‐performance proton‐conducting solid oxide fuel cells

Abstract

Abstract A nonmetal doping strategy was exploited for the conventional La 0.5 Sr 0.5 FeO 3‐ δ (LSF) cathode, allowing high performance for proton‐conducting solid oxide fuel cells (H‐SOFCs). Unlike previous studies focusing on the utilization of metal oxides as dopants, phosphorus, which is a nonmetal element, was used as the cation dopant for LSF by partially replacing Fe ions to form the new La 0.5 Sr 0.5 Fe 0.9 P 0.1 O 3‐ δ (LSFP) compound. The H‐SOFC using the LSFP cathode showed a two‐fold peak power density as compared to that using the LSF cathode. Both experimental studies and first‐principle calculations were used to unveil the mechanisms for the high performance of the LSFP cells.