A facile pyrolysis method to prepare vanadium oxides for high performance aqueous Zn-ion battery

Abstract Vanadium oxides, as one of the most promising cathode materials for zinc ion batteries, have attracted extensive attention in recent years. Different from the generally used hydrothermal and solvothermal methods to adjust the composition, structure, morphology and electrical properties of vanadium oxides, we firstly adopt a simple pyrolysis method to synthesize a series of vanadium oxides and use them as cathode materials for aqueous Zn-ion battery, whose electrochemical performances is superior to most state-of-the-art vanadium oxides. The as-obtained V4O7 under the calcination temperature of 700 °C exhibits excellent zinc ion storage performance with maximum specific capacity of 367.2 mAh g−1 at the current density of 1 A g−1, about 84.9% capacity retention after 100 cycles, excellent rate performance, high capacity. In addition, a series of structural and electrochemical characterization are used to reveal the possible mechanism of charge and discharge.