A novel facile strategy to suppress Sr segregation for high-entropy stabilized La0·8Sr0·2MnO3-δ cathode

Abstract Sr segregation on a perovskite oxide surface immensely affects the oxygen reduction activity and the durability of solid oxide fuel cells cathode. Herein, a facile strategy is proposed, which employs a high-entropy perovskite oxide as a cathode to suppress the Sr segregation during the long-term operation. The as-prepared high-entropy La0·8Sr0·2MnO3-δ (LSM) incorporates five components into A-site of LSM perovskite, including La, Pr, Nd, Sm and Sr (La0.2Pr0.2Nd0.2Sm0.2Sr0·2MnO3-δ, HE-LSM). The homogeneously dispersive multiple rare-earth metal species in A-site of perovskite are thermodynamically stable at high temperature. Besides, the lattice distortion of HE-LSM caused by the high dispersity of A-site cations will lead to the formation of disordered stress field around Sr, which can limit the transport rate of Sr. Further long-term stability test indicates that HE-LSM is rather stable under the operation condition, demonstrating that high-entropy perovskite oxide is a potential cathode material which can suppress the cation segregation for solid oxide fuel cell.