High performance bilayer 2D VO cathode for Zn-ion and Zn/Li hybrid metal-ion intercalation battery.

The deteriorating and unevenly distributed Li reserves lead to the quest for Li-ion battery's alternatives.Hybrid metal-ion batteries are gaining attention as they effectively address the limited diffusion of heavier ions into cathode materials, typically involving the combination of multi and mono-valent metal-ions.The unavailability of high-performance cathode materials restricts the use of heavier ion (e.g., Zn) intercalation batteries even though they offer more stable anodic behavior and good charge capacity. In the present study, bilayer VO nanosheets demonstrate exceptional performance as a cathode material for Zn-ion battery and Zn/Li hybrid metal-ion battery facilitating a faster conduit of ion diffusion. The Zn-ion battery and Zn/Lihybrid metal-ion battery showed high specific capacities of 270 and 510 mAh/g with fast charging rates of 0.77, and 0.6 A/g, respectively. Li is a lighter ion with an ionic radius of 0.76Å compared to the Zn ion that of 0.74Å and hence has shown higher diffusion into the crystal. The introduction of Li in the hybrid metal-ion battery showed good cyclic performance with high coulombic efficiency. Thus, this study presents bilayer 2D VO as a favorable cathode material for Zn-ion and Zn/Li hybrid metal-ion batteries for the first time.