Synthesis of Zn Intercalated Zn-V@Mo-V Nanorods-based Cathodes for Prolonged Cyclic Stability of Rechargeable Aqueous Zinc-Ion Batteries

Stationary rechargeable Zn-ion batteries (ZIBs) are attractive energy storages systems because of their natural abundance, safety, and low cost. High capacity, stable, and robust cathode materials play an important role in aqueous electrolyte systems in ZIBs, where metal oxide cathode dissolution is a problem that needs to be addressed. Herewith, we report an intercalation-type Zn-doped Zn-V@Mo-V (ZMV) cathode material affording prolonged cycle stability and high storage capacity. Porous, superfine nanostructures offer Zn2+ ion diffusion pathways, alleviating intercalation redox reactions without dissolution. Zn doping restructures the cathode expansion-like, resulting in increased electrical conductivity and faster electrochemical ion diffusion. A reversible and uniform Zn electro-plating at the anode surface interface indicates improved cell reversibility. The ZMV cathode scales up to assemble a pouch cell of Zn//ZnSO4//ZMV, where the cathode enhances the rate performance and decreases the self-discharge rate. High efficiency and long cycle life can be endowed to the cathode material to construct a stable Zn-ion battery, accelerating the commercialization of the whole system.