A new and effective synthesis of non-stoichiometric metal oxides such as oxygen-deficient WO2.72

Abstract

A new method for the quantitative synthesis of non-stoichiometric oxides such as WO_2.72 is described. The method involves the pyrolysis of an acidified mixture of sodium tungstate and ammonium polyacrylate under argon. The tungsten carbide-containing product of the pyrolysis is carefully oxidised under carbon dioxide in order to produce well-defined needles of the tungsten oxide.