NANORODS OF VANADIUM COMPOUNDS

Abstract

The synthesis and characterisation of nanorods of vanadium pentoxide, V2O5, vanadium trioxide, V2O3, vanadium dioxide, VO2(B), and vanadium nitride, VN, are presented, and their application in electrochemical supercapacitors and lithium-ion batteries is outlined. Specifically, a novel method for the preparation of V2O5 nanorods is discussed. It involves ball milling as a first step and controlled annealing as a second step Nanorods of V2O5 can be converted into those of other vanadium-related phases by simple chemical reduction treatments Such chemical transformations are pseudomorphic and often topotactic, that is, the resulting nanorods belong to a different chemical phase but tend to retain the original morphology and preferential crystal orientation dictated by parent V2O5 crystals. The corresponding properties of nanorods for their prospective application in electrochemical energy storage (lithium-ion batteries and electrochemical supercapacitors) are discussed. The synthesised V2O5 nanorods possess a stable cyclic behaviour when they are used in a cathode of a lithium-ion battery and are suitable for use in an anode. VN nanorods synthesised by NH3 reduction of V2O5 were found to possess pseudocapacitive properties in aqueous electrolytes. Show more