Layered Barium Vanadate Cathodes for Aqueous Zinc Batteries: Enhancing Cycling Stability through Inhibition of Vanadium Dissolution

The development of cathode materials has always been the key to improve the performance of aqueous zinc-ion batteries (AZIBs). The issue of cathode material dissolution in aqueous electrolytes is a critical problem that needs urgent attention and exact solutions. In this article, a cathode composed of Ba_0.26V₂O₅·0.92H₂O nanobelts has been successfully synthesized. AZIBs using this material as cathode deliver high capacity up to 384.93 mA h g^–1 at 0.05 A g^–1, owing to the resident cation Ba²⁺ and crystal water in the vanadium oxygen layers, which enlarge the interlayer distance and improve the ion-migration speed. More importantly, excellent cycle stability and rate performance are achieved because of the formation of the BaSO₄ cathode–electrolyte interphase (CEI) film. This film can inhibit the dissolution of V ions effectively.