Engineering Antiperovskite Ni4N/VN Heterostructure with Improved Intrinsic Interfacial Charge Transfer as a Bifunctional Catalyst for Rechargeable Zinc–Air Batteries

Development of an oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) bifunctional electrocatalyst based on a low-cost and earth-abundant raw material is pivotal for large-scale application of rechargeable zinc–air batteries (ZABs). Herein, an antiperovskite Ni4N/VN heterostructure anchored on nitrogen-doped graphene (Ni4N/VN–NG) was designed and synthesized. Both experimental and theoretical results suggest that the electronic coupling between Ni4N and VN can regulate the electronic structure of the catalyst for promoted catalytic kinetics. Remarkably, the Ni4N/VN–NG exhibited excellent bifunctional catalytic activity and stability with an overvoltage difference of 0.75 V. The ZABs with Ni4N/VN–NG as the air cathode can achieve a high-power density of 140 mW cm–2 and a long-term operational stability for 180 h, superior to the battery with commercial Pt/C and RuO2 catalysts. This work proposes the construction of pretransition metal and post-transition metal nitride heterojunctions to promote ORR/OER activity and provides a new strategy for the rational design and synthesis of efficient oxygen bifunctional electrocatalysts for ZABs.