Boosting Charge Carrier Transport by Layer‐Stacked MnxV2O6/V2C Heterostructures for Wide‐Temperature Zinc‐Ion Batteries

Abstract

AbstractVanadium‐based materials are considered promising cathodes for high‐energy‐density zinc‐ion batteries (ZIBs) owing to their open skeleton structure and multielectron redox reactions. However, most vanadium‐based materials have low intrinsic conductivities and sluggish reaction kinetics, resulting in poor cycling properties. Herein, a layer‐stacked MnxV2O6+V2CTx (MVO+V2C) heterostructure cathode with high capacity and superior cyclic stability based on an electrostatic self‐assembly strategy is proposed. The abundant heterointerfaces between MVO and V2C dramatically enhanced the intrinsic conductivity of the composites. Moreover, the generation of built‐in electric fields at the layer‐stacked MVO/V2C heterointerface reduced the migration energy barrier of Zn2+, accelerated charge carrier transport, and enhanced the reaction kinetics of the cathode. In addition, the abundance of nano‐channels in the heterostructures facilitates rapid electrolyte transport in composites. Therefore, the MVO+V2C cathode showed a capacity of 389.4 mAh g−1 after 590 cycles at 0.5 A g−1 and 290.2 mAh g−1 after 6000 cycles at 5 A g−1, demonstrating its superior cycling stability. In particular, the assembled MVO+V2C batteries exhibited remarkable electrochemical performance at −20–40 °C, revealing its excellent wide‐temperature adaptability. This work offers important insights into the design of cathode materials for long‐lifespan and wide‐temperature ZIBs.