Cu97P3-x-yOxNy/NPC as a bifunctional electrocatalyst for rechargeable zinc-air battery

Abstract

Developing highly efficient and economically sustainable electrocatalysts with bifunctions for the oxygen reduction reaction and oxygen evolution reaction is crucially important in practical implementation of rechargeable zinc-air batteries. Herein, a novel Cu-based electrocatalyst composed of Cu97P3-x-yOxNy nanoparticles supported on N, P co-doped carbon is synthesized straightforward by the annealing of the Cu-phytic acid gel under an argon and ammonia gases atmosphere. The Cu97P3-x-yOxNy/N, P co-doped carbon catalyst displays the outstanding catalytic performance for both the oxygen evolution reaction and oxygen reduction reaction in alkaline solution, which is ascribed to the synergistic effect of Cu97P3-x-yOxNy and N, P co-doped carbon. Meanwhile, the primary and rechargeable zinc-air batteries assembled by the Cu97P3-x-yOxNy/N, P co-doped carbon catalyst exhibit a high specific capacity and remarkable charge-discharge cycle stability, which are comparable to that of the benchmark Pt/C and IrO2. The energy density of the catalyst reaches to 737 Wh kgZn−1. To the best of our knowledge, few Cu-based electrocatalysts is reported for rechargeable zinc-air batteries.