Hierarchical Porous Intercalation-Type V O as High-Performance Anode Materials for Li-Ion Batteries.

As intercalation-type anode materials for Li-ion batteries (LIBs), the commercially used graphite and Li Ti O exhibit good cycling and rate properties, but their theoretical specific capacities are too low to meet the ever-growing demands of high-energy applications such as electric vehicles. Therefore, the development of new intercalation-type anode materials with larger capacity is very desirable. Herein, we design and synthesize novel 3 D hierarchical porous V O @C micro/nanostructures consisting of crumpled nanosheets, through self-reduction under annealing from the structurally similar VO (B)@C precursors without the addition of any other reducing reagent or gas. Excitingly, it is found for the first time through ex situ XRD technology that V O is a new, promising intercalation-type anode material for LIBs with a high capacity. V O @C micro/nanostructures can deliver a large capacity of 732 mAh g without capacity loss at 100 mA g even after 136 cycles, as well as exhibiting excellent cycling and rate performances. The application of V O for Na-ion batteries (NIBs) is elaborated for the first time, and excitingly, it is found that V O @C micro/nanostructures may be promising anode materials for NIBs.