Nickel-mediated polyol synthesis of hierarchical V2O5 hollow microspheres with enhanced lithium storage properties

Abstract

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.