Heterointerface Built Up by Ultrathin Amorphous MoO3 Conformal Coating Enables V5O12·6H2O with Superior Properties for Aqueous Zinc Batteries

Layered V5O12·6H2O is a promising candidate for aqueous zinc batteries (AZBs) but with moderate electrochemical performances. Herein, the charge storage properties of V5O12·6H2O are markedly improved by building up the heterointerface on its surface using amorphous molybdenum trioxide as the heteromaterial. The amorphous molybdenum trioxide functioning as the proton reservoir enables the proton-involved electrochemical reactions and induces the formation of a built-in electric field along the [001] orientation at the heterointerface constructed by the (001) plane of V5O12·6H2O, which could provide new diffusion pathways and extra sites for ion storage. As a result, V5O12·6H2O with significantly improved kinetics realizes an ultrahigh capacity of 510 mAh g-1, better rate capability, and prolonged lifespan. This work provides general guidance for designing advanced cathode materials for AZBs with respect to heterostructure.