Controllable Synthesis of Skeletonized V₂O₅ Microspheres Derived from a V‑MOF for Aqueous Zinc-Ion Batteries

Low-cost, environmentally friendly aqueous zinc-ion batteries (ZIBs) exhibit tremendous potential in energy storage; however, the research of cathode materials that enable meeting the requirements of high capacity and cycling performance is still in the exploratory stage. This research synthesizes unique skeletonized V₂O₅ microspheres by facile calcination using a spherical vanadium metal–organic framework (V-MOF) as the template. Owing to the three-dimensional porous structure, the V₂O₅ cathode considerably enhances the kinetics of the ionic reaction. In addition, the prepared V₂O₅ has a mixed valence state, which improves the electrochemical activity and reduces the polarization. As a result, its application as the cathode in aqueous ZIBs exhibits excellent electrochemical qualities. It reaches a remarkable specific capacity of 449 mA h g^–1 at 0.5 A g^–1, and the specific capacity remains at 200 mA h g^–1 after 1400 cycles at 5 A g^–1. These excellent performances indicate that V₂O₅ prepared as a cathode material for aqueous ZIBs shows significant prospects.