Three-dimensional hydrated vanadium pentoxide/MXene composite for high-rate zinc-ion batteries.

Aqueous zinc-ion batteries (ZIBs) have been considered to be potential energy storage devices because of their cost-effectiveness and environmental friendliness. However, most of the cathode materials reported in ZIBs exhibit poor electrochemical performances like capacity fading during cycling and inferior performance at high current densities, which significantly hinder the further development of ZIBs. Here, we reported a novel three-dimensional hydrated vanadium pentoxide (VO·nHO)/MXene composite via a simple one-step hydrothermal method. Owing to the unique structure and high electrical conductivity of MXene, VO·nHO/TiCT MXene shows a remarkable electrochemical performance with a reversible capacity of 323 mAh g at 0.1 A g and exceptional rate capability (262 mAh g at 1 A g and 225 mAh g at 2 A g) when used as the cathode for aqueous ZIBs. This work offers a new insight into fabricating novel vanadium oxide-based cathode material for aqueous ZIBs.