Description:
A general strategy is explored to design and synthesize a series of layered vanadate hydrates. Structural analysis found a small amount of cations entered into the VO layers to form a chemical bonding and lock the layer slabs with a stable structure. The stabilized vanadate hydrates have the expanded layer spacing and the robust layered structures that provide a fast ion migration channel and stand the volume change in the intercalation/de-intercalation of Zinc-ion during the electrochemical reaction, rendering an excellent rate capability and stable cycling performance. Specifically, Mn-stabilized vanadium pentoxide hydrate delivers a specific capacity of 400 mAh/g at a current density of 50 mA/g and 260 mAh/g at 4 A/g with capacity retention of 92% over 2,000 cycles. Several transition metal cations can also play the same role in enhancing Zn-ion storage in layered vanadate hydrates, suggesting a general strategy for exploiting the high-performances cathodes for multi-valent ion batteries.