Strong electronic coupling of NiCo2O4 and CeO2 regulates the nucleation and decomposition of Li2CO3 for high-rate performance Li–CO2 batteries

Abstract

The sluggish CO2 reduction/evolution kinetics at the cathode severely hamper the industrial applications of Li–CO2 batteries, especially under large current densities. Herein, NiCo2O4/CeO2 with a strong electron coupling effect is prepared via solvothermal method and calcination to realize the rapid kinetics of discharge and charge processes. The electronic character of the catalyst and the growth behavior of Li2CO3 are investigated through density functional theory (DFT) and experiments, elucidating the reaction mechanism of Li–CO2 battery. The results demonstrate that the strong electronic coupling of NiCo2O4 and CeO2 enhances the intrinsic activity of the catalyst and promotes the generation of membrane-like Li2CO3 with good reversibility, thereby enhancing battery performance at a large current density. Consequently, NiCo2O4/CeO2 achieved a large specific capacity of 7767 mAh g−1 under 2000 mA g−1 and could be stably cycled more than 240 times, outperforming most reported metal-based catalysts. This work underscores the important role of strong electronic coupling in facilitating the formation and decomposition of Li2CO3, providing valuable insight for designing cathode catalysts with high-rate properties for Li–CO2 batteries.