S-Doped La0.8Sr0.2(CrMnFeCoNi)O3 High Entropy Perovskite As Efficient Bifunctional Oxygen Evolution Reaction/Oxygen Reduction Reaction Electrocatalyst

Developing non-noble metal, low cost, highly efficient and stable bifunctional oxygen evolution reaction (OER)/oxygen reduction reaction (ORR) electrocatalyst has attracted significant interests for several applications such as metal air battery. Herein, we report an S-doped high entropy perovskite oxide (HEPO) of La 0.8 Sr 0.2 (CrMnFeCoNi)O 3 electrocatalyst for bifunctional OER/ORR electrocatalyst. We show that S-doped La 0.8 Sr 0.2 (CrMnFeCoNi)O 3 electrocatalyst exhibits a low OER overpotential of 385 mV at 10 mA cm -2 and a half-wave potential of 0.728 V for ORR in 0.1 M KOH. The electrocatalyst also demonstrates excellent stability. Various in-situ analyses were performed to investigate the morphological and structural change of electrocatalyst during the OER and ORR processes. This study opens a new opportunity for further exploring advanced bifunctional electrocatalyst.