Synthesis and characterization of self-assembled nanofiber-bundles of V2O5: their electrochemical and field emission properties

Abstract

High-quality self-assembled V₂O₅ nanofiber-bundles (NBs) are synthesized by a simple and direct hydrothermal method using a vanadium(V) hydroxylamido complex as a vanadium source in the presence of HNO₃. The possible reaction pathway for the formation of V₂O₅ NBs is discussed and demonstrated that HNO₃ functions both as an oxidizing and as an acidification agent. V₂O₅ NBs are single-crystals of an orthorhombic phase that have grown along the [010] direction. A bundle is made of indefinite numbers of homogeneous V₂O₅ nanofibers where nanofibers have lengths up to several micrometres and widths ranging between 20 and 50 nm. As-prepared V₂O₅ NBs display a high electrochemical performance in a non-aqueous electrolyte as a cathode material for lithium ion batteries. Field emission properties are also investigated which shows that a low turn-on field of ∼1.84 V μm⁻¹ is required to draw the emission current density of 10 μA cm⁻².