Solution combustion synthesis of nanosized WOx: characterization, mechanism and excellent photocatalytic properties

Various nanoscale tungsten oxides with excellent photocatalytic properties were synthesized via an ultra-rapid solution combustion synthesis method. The results indicated that the WO3 and W18O49 could be synthesized with different fuels (glycine, urea, urea and citric acid) and the powders presented mesoporous structures with different morphologies such as nanoparticles, nanorods and nanoneedles. Detailed reaction mechanisms of various systems were identified, and the specific roles of different fuels were discussed. Moreover, the synthesized powders displayed excellent photocatalytic efficiency, degrading organic compounds in 50 min under UV-visible light irradiation. The work suggests that solution combustion synthesis can be used as a new strategy to design nanosized stoichiometric and oxygen-vacancy-rich nonstoichiometric oxides with excellent properties.