Nitrogen-doped strategy derived Co3O4/carbon nanosheets as high-performance oxygen electrocatalysis for rechargeable zinc-air batteries application

Doping engineering has a crucial role in improving the electrocatalytic oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). However, research on heteroatom doped electrocatalysts as high-performance rechargeable zinc-air batteries application still maintain a significant challenge. Herein, nitrogen-doped Co3O4 on nitrogen-doping carbon nanosheets (referred to as N-Co3O4/N-CNs) were constructed by utilizing a facile N-doped strategy. The N-Co3O4/N-CNs catalysts exhibited outstanding OER/ORR activity such as low overpotential (354 mV@10 mA cm-2) and large half-wave potential (0.79 V), as well as good stability in alkaline solutions. Furthermore, excellent catalytic performances were mainly ascribed to N-doping engineering, which optimized electronic structure of Co species, promoted intrinsic catalytic activities, accelerated charge transfer and exposed more active sites for oxygen electrocatalytic process. More interestingly, when assembled as an air cathode for Zn-air batteries application, N-Co3O4/N-CNs delivered an outstanding power density of 126.7 mW cm-2, a high specific capacity of 754.0 mA h g-1 and outstanding cycling stability, surpassing that of commercial Pt/C-RuO2 and most of Co3O4-based Zn-air batteries. This research provides a promising approach for designing highly-efficient Co3O4-based electrocatalysts for Zn-air batteries application.