A ZnFeNiCoCr high‐entropy alloy for efficient bifunctional oxygen electrocatalysis

Abstract The dearth of efficacious and economic bifunctional oxygen electrocatalysts has constituted a significant impediment to the actual implementation of high‐performance metal‐air batteries. Here, we construct an efficacious bifunctional oxygen electrocatalyst ZnFeNiCoCr high‐entropy alloy (HEA) nanoparticles for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) using a facile sol–gel strategy. The synthesized ZnFeNiCoCr HEA exhibits excellent bifunctional properties due to the synergistic effect between the metal elements. The overpotential of 305 mV at 10 mA·cm −2 for OER and a half‐wave potential of 0.864 V for ORR, which is excellent to that of commercial RuO 2 and Pt/C. Consequently, ZnFeNiCoCr HEA is utilized as a cathode catalyst for zinc‐air batteries. The specific capacity of a zinc‐air battery based on this HEA is 743 mAh·g −1 and the battery undergoes a continuous charge/discharge cycle for over 400 h. The ZnFeNiCoCr HEA catalyst holds significant application potential in diverse electrochemical energy storage and conversion devices.