Field emission of vertically aligned V(2)O(5) nanowires on an ITO surface prepared with gaseous transport

Abstract

Growing V(2)O(5) nanowires (NWs) on a conducting glass substrate combines gaseous transport and pyrolytic deposition of vanadium polyoxometalate anions, and yields vertically aligned vanadium-oxide nanowires. Scanning electron and transmission electron microscopy, selected-area electron diffraction, Raman spectra and powder X-ray analyses indicate that V(2)O(5) nanowires as synthesized were single-crystalline and grew anisotropically among direction [010]. NH(2)OH center dot HCl served not only as a reducing agent to produce vanadium polyoxometalate clusters but also as a source of NH(3) gas to facilitate the vapor pyrolysis and deposition. The optical properties of V(2)O(5) nanowires exhibit a character dependent on structure. Field emission (FE) measurements show a small turn-on field voltage similar to 8.3V/mu m, maximum Current density 1.8 mA/cm(2), and a linear Fowler-Nordheim behavior. (C) 2009 Elsevier Inc. All rights reserved.