In Situ Grown V ₃ O ₇ ·H ₂ O Nanosheets on Reduced Graphene Oxide for High-Performance Aqueous Zinc-Ion Battery Cathodes

Vanadium-based oxides possess remarkable charge storage capability and variable valence states for zinc-ion intercalation; nevertheless, their real-world application is significantly constrained by inherent drawbacks such as low intrinsic conductivity and structural instability. This work produced a V 3 O 7 ·H 2 O/rGO composite cathode (VOH/rGO) through a straightforward single-step hydrothermal approach. When graphene oxide forms reduced graphene oxide during the hydrothermal process and is combined with the material, it enhances the material’s electrical conductivity and specific surface area, generating a large number of active sites. Consequently, Zn 2+ migration between the electrode and electrolyte was boosted, resulting in fast reaction kinetics. The rationally constructed VOH/rGO-2 composite cathode exhibits 430.7 mAh g –1 reversible capacity at 0.5 A g –1 and 290 mAh g –1 at 5 A g –1 . This work offers a promising direction for designing robust, high-capacity composite cathodes for aqueous zinc-ion batteries.