Growth and characterization of stoichiometric tungsten oxide nanorods by thermal evaporation and subsequent annealing

Abstract

Stoichiometric tungsten oxide (WO3) nanorods are synthesized on tungsten ( W) substrates by a high- temperature, catalyst- free, physical deposition process and by subsequent annealing in oxygen atmosphere. Tungsten oxide nanorods are grown by thermal evaporation of WO3 powder at elevated temperature in a tube furnace. XRD, TEM and XPS analysis shows that the as-grown nanorods are single crystalline and non-stoichiometric ( WOx). Annealing of WOx nanorods at 700 degrees C under oxygen atmosphere has led to the formation of stoichiometric WO3 as evidenced by XRD, XPS and Raman analysis.