Freestanding CuV2O6/carbon nanotube composite films for flexible aqueous zinc-ion batteries

Freestanding CuV2O6/reductive acidified carbon nanotube (CVO/RCNTs) composite films with excellent flexibility and conductivity were prepared via a vacuum filtration strategy and made into the aqueous Zn//CVO/RCNTs gel battery, which exhibited stable electrochemical properties under different bending conditions. [Display omitted] •Free-standing CuV2O6/RCNTs composite films with high flexibility were achieved.•RCNTs provided a 2 µm conductive substrate for the film as a current colletor.•The aqueous Zn//CVO/RCNTs gel battery exhibited stable electrochemical properties.•Great potential as flexible wearable energy storage devices. Rechargeable aqueous zinc-ion batteries (ZIBs) have become a key research object in the field of new generation energy storage devices due to their high safety, low cost and eco-friendliness, and show a promising potential application. In this work, CuV2O6 nanobelts were synthesized by the hydrothermal method and freestanding CuV2O6/reductive acidified carbon nanotube (CVO/RCNTs) composite film without any binder was synthesized by vacuum filtration. The aqueous Zn//CVO/RCNTs batteries presented a admirable reversible capacity of 353 mAh g−1 at 0.1 A g−1 and the cycling performance with a high reversible capacity of 174.7 mAh g−1 and 61.5% capacity retention after 1400 cycles at 5 A g−1,making rings round the vast majority reported zinc ion batteries.More importantly, the CVO/RCNTs composite films had stable electrochemical properties under different bending degrees after preparation into flexible gel batteries, demonstrating great potential in the field of flexible wearable zinc ion batteries.