MOF–Derived N–Doped C @ CoO/MoC Heterojunction Composite for Efficient Oxygen Reduction Reaction and Long-Life Zn–Air Battery

Abstract

The high activity and reliability of bifunctional oxygen catalysts are imperative for rechargeable metal–air batteries. However, the preparation of bifunctional non–noble metal electrocatalysts with multiple active sites remains a great challenge. Herein, an MOF–derived N–doped C–loaded uniformly dispersed CoO/MoC heterojunction catalyst for high–performance dual function was prepared by a simple “codeposition–pyrolysis” method. Experimental investigations revealed that the formation of the heterojunction can tailor the valence of Co and Mo sites, which impressively modulates the electronic properties of the active sites and promotes the electrocatalytic processes. The optimal catalyst reveals a high–wave half potential (E1/2 = 0.841 V) for ORR and a low overpotential (E10 = 348 mV) for OER. The NCCM–600–based Zn–air battery displays a high peak power density of 133.36 mW cm−2 and a prolonged cycling life of more than 650 h. This work provides avenues for the development of functional materials with enhanced properties in a variety of practical energy applications.

Keywords

• heterojunction
• oxygen reduction reaction
• Zn–air battery