Nickel-mediated polyol synthesis of hierarchical V2O5 hollow microspheres with enhanced lithium storage properties†
In this study, a facile template-free synthesis of hierarchical V2O5 hollow microspheres has been developed, based on a nickel-mediated polyol process and subsequent calcinations. It is found that morphological control over V2O5 micro-architecture is realized by adding Ni into the polyol process. XPS results demonstrate that Ni doping promotes the formation of low valence state vanadium in V2O5 samples and is beneficial to maintain electric stability to the V4+ state. Due to unique structure and low valence state vanadium in Ni–V2O5 microspheres, Ni (10 mol%)–V2O5 used as the cathode material for a lithium ion battery exhibits excellent lithium storage properties with very high capacity (294 mA h g−1) and superior cycling stability and rate performance. The good electrochemical performance suggests that this hierarchical Ni–V2O5 material could be a promising candidate as a cathode material for lithium-ion batteries.