Isolated p-Block Antimony Atoms Activated CuO@Co-CN Enable High Performances for Water Splitting and Zn-Air Batteries

This study reports an effective strategy for designing 3D electrocatalyst via the deposition of ZIF67-derived Co-CN shell layer over CuO nanoarrays to form a CuO@Co-CN hybrid, followed by incorporation with p-block Sb single atoms (CuO@Co-CN/Sb) to obtain highly activated catalytic behaviors. Inheriting both the excellent intrinsic catalytic activity of the components and their synergy, the CuO@Co-CN/Sb material serves as a high-efficiency multifunctional catalyst for overall water splitting and zinc (Zn)-air batteries. The material yields a current density of 10 mA cm^-2 at a low overpotential of 72 and 250 mV for the hydrogen evolution reaction and oxygen evolution reaction, respectively. Furthermore, an electrolyzer based on CuO@Co-CN/Sb shows remarkable performance with a derived current density of 0.5 A cm^-2 at low cell voltage of 2.67 V and good stability for 50 h continuous operation at a high current density of 0.5 A cm^-2. Simultaneously, Zn-air battery using the CuO@Co-CN/Sb material as air cathode yields a high open circuit voltage of 1.455 V and a discharge power density of 131.07 mW cm^-2.