Y-doped V2O5 with enhanced lithium storage performance

Abstract

Y-doped V₂O₅ was prepared by the sol–gel method combined with the freeze drying technique followed by annealing in air. The microstructure of the Y-doped V₂O₅ was analyzed by XRD, SEM, XPS, and first-principles calculations. The electrochemical performance of the Y-doped V₂O₅ was characterized by CV, EIS, and charge–discharge tests. The results demonstrated that Y doping had great influence on the morphology and crystalline orientation of the prepared V₂O₅ sample. In particular, Y formed covalent bonds with the adjacent O atoms within the V₂O₅ layers and decreased the bond orders of the neighboring V–O bonds. Compared with undoped V₂O₅, Y-doped V₂O₅ showed much improved rate capability, higher lithium ion diffusion coefficient, lower electrochemical reaction resistance, and greatly enhanced cycling stability. Y-doped V₂O₅ could be a promising cathode material for lithium ion batteries.