Localized Ostwald Ripening Guided Dissolution/Regrowth to Ancient Chinese Coin-shaped VO2 Nanoplates with Enhanced Mass Transfer for Zinc Ion Storage

Charge and mass transfer at the interface between electrode and electrolyte are of vital significance for energy conversion and storage in aqueous rechargeable zinc ion batteries (ZIBs). Approaching rational design and preparation of unique nanostructures with enhanced mass transfer is still facing great challenges in response to these problems. Herein, the highly uniform and round new-state nsutite-type vanadium dioxide (VO2) nanoplates with novel ancient Chinese coin structure (with thickness of approximate to 50 nm and diameter of approximate to 500 nm, with a hole in the middle) are prepared successfully. During the hydrothermal process, the VO2 nanoplate undergoes an interesting Ostwald ripening guided dissolution-regrowth process, resulting in the formation of the unusual ancient Chinese coin structure. Impressively, based on structural merits of the abundant electrolyte-accessible sites and transfer pathways, the mass transfer can be enhanced at the surface of as-prepared VO2 nanoplates-based electrode. The VO2 nanoplates further deliver high reversible specific capacity and rate ability for rechargeable ZIBs. Hence, this work presents a new avenue for designing unique nanostructure vanadium oxides to boost the electrochemical properties of aqueous ZIBs.