Ultralong single crystalline V2O5nanowire/graphene composite fabricated by a facile green approach and its lithium storage behavior

Abstract

A novel hybrid material constructed from 2D graphene nanosheets (GNS) and 1D vanadium pentoxide (V₂O₅) nanowires was successfully fabricated via a very simple green approach. The ultralong V₂O₅ single crystalline nanowires were supported on the transparent GNS substrate and exhibited excellent electrochemical properties. When used as a cathode material of lithium-ion batteries, the composite material revealed high initial discharge capacities and exceptional rate capacities. For instance, at the lower current density of 50 mA g⁻¹, an initial specific discharge capacity of 412 mAh g⁻¹ could be achieved; when the current density was increased to 1600 mA g⁻¹, the composite still delivered 316 mAh g⁻¹lithium ions. The good performance of the composite resulted from its unique nano-scaled V₂O₅ wires with short diffusion pathway for lithium ions and the excellent electrical conductivity of GNS. Note that the fabrication approach in the present work is environmental friendly without any strong reduction and oxidation reagents, or causing the generation of toxic gas during the fabrication process. We believe that this green approach may open up the possibility of fabricating more novel structured graphene-based functional materials.