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.