Co doped V2O5 hollow microsphere as high-performance cathode for aqueous zinc-ion battery

V₂O₅ is widely used as a cathode material for aqueous zinc ion batteries (AZIBs) due to its high theoretical capacity, diverse valence states and high electrochemical activity. However, the inherent issues of poor cycle stability and low conductivity limit its further application. In this study, vanadium-based metal organic frameworks (V-MOFs) are used as templates to synthesize Co-doped V₂O₅ with porous spherical structure by hydrothermal and calcination methods. The construction of the hollow structure promotes the diffusion of the electrolyte, alleviates the volume expansion of the electrode during the cycling process, and effectively enhances the electrochemical stability. Co doping can efficiently stabilize V-O bonds and suppress the dissolution of vanadium. The results show that the material exhibits excellent performance, delivering a capacity of 437 mAh g⁻¹ at 0.2A g⁻¹. After 1400 cycles at 5A g⁻¹, the capacitance of the material remain at 87.5 %, and possess the lowest charge transfer resistance (184Ω), indicating that doping Co can effectively enhance conductivity and stabilize the crystal structure, thereby improving electrochemical stability. This research pioneers a new approach toward generating better cathode materials for AZIBs.