Interfacial oxygen bridge bonding with Mo-O-Ti units in MoOx@Ti3C2 MXene harness efficient Li-O2 Battery at high rate

Abstract

The rational pursuit of competent bifunctional catalysts for facilitating oxygen redox kinetics is critical in boosting the Li-O2 battery commercial application. Here, we report the preparation of efficient MoOx@Ti3C2 MXene catalysts with optimized electronic structure by in-situ incorporation of interfacial oxygen bridge bonding with Mo-O-Ti units. MoOx@Ti3C2 MXene delivers tailored chemical bonding, amplified electrical conductivity, and outstanding high-rate stability. The as-constructed MoOx@Ti3C2 MXene-based Li-O2 battery achieves lower discharge/charge polarization of 0.75 V and long-term lifespan of 300 hours (over 300 cycles) under 2500 mA g−1, exceeding those of reported related catalysts. Density functional theory analysis and ex-situ experiments reveal the critical role of bimetallic-oxygen coupling in regulating the micro-chemical constitution and controlling the Li2O2 formation mode. This work could provide consideration insights in the rational design of competent and stable MXene-based cathode catalyst with bimetallic heterostructure for high-rate Li-O2 batteries.