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

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 similar to 1.84 V mu m(-1) is required to draw the emission current density of 10 mu Lambda cm(-2).