Vanadium oxide/carbonized chestnut needle composites as cathode materials for advanced aqueous zinc-ion batteries

Owing to the abundance of zinc, inherent safety, simple assembly-operation and inexpensive nature, aqueous zinc ion batteries (AZIBs) as high-potential electrochemical energy devices hold marvelous development prospects. V2O3 as one of the promising AZIBs cathode materials has been severely limited due to its low electron conductivity and large volume variation during charge/discharge. In this study, the V2O3/carbonized chestnut needle (V2O3/CCN) composites were successfully prepared by a simple evaporation-induced self-assembly technique, using NH4VO3 and chestnut needle as raw materials. The introduction of biomass derived carbon not only provides a channel to ensure rapid electron/ion transport but effectively enhances the structural stability and electrical conductivity of V2O3. Benefiting from the above-mentioned positive effects, V2O3/CCN-15/2 electrode possess an exceptional discharge capacity of 431.96 mAh g−1 at 0.05 A g−1 and a fabulous cycle capability of 201.41 mAh g−1 (capacity retention of 94.27 %) at 3 A g−1 after 1000 cycles. The desirable electrochemical performance of V2O3/CCN-15/2 is proved by ex-situ testing methods. The insights provided by this investigation may contribute to the development of AZIBs cathode materials with competitive potential that are expected to play a paramount role in future large-scale energy storage.