Vanadium-based compounds for aqueous zinc ion batteries with excellent rate capability and cyclic stability

Zinc ion battery (ZIB) is becoming a research hotspot because of its high safety, low cost and environmental protection, and will become a promising new energy storage device. Vanadium-based compounds are widely investigated as positive materials because of their multivalency, rich crystal structure and high specific capacity. In this work, three vanadium-based compounds V2O5, V2O3 and VN samples are prepared by hydrothermal and solid-phase synthesis methods. The phase structure and purity of synthetic materials are demonstrated X-ray Diffraction (XRD). Morphology characterization shows that V2O5, V2O3 and VN samples have nanosheets, nanoflakes and nanoparticles structures, respectively. In addition, the electrochemical properties of V2O5, V2O3 and VN samples in ZIBs are systematically investigation. These three vanadium-based compounds all have great cycle stability and high-rate capabilities. This work provides guidance for the development of novel vanadium-based electrode materials and paves the way for the development of zinc ion storage.