Studies on fabrication of urchin-like WO3•H2O hollow spheres and their photocatalytic properties

Urchin-like tungsten oxide hydrate (WO3 center dot H2O) hollow spheres were successfully synthesized via a self-sacrifice template method at low temperature. The effects of reaction parameters on the preparation were studied in solution. The growth mechanism was also proposed on the basis of experimental results. In addition, the acid amount and temperature have important effects on size control of the as-obtained samples. The achieved nanoarchitectures have typical diameters of 46 m with nanoflakes of several nanometers at surface. Crystal structure, morphology, and composition of final nanostructures were characterized by Xray diffraction (XRD) and scanning electron microscopy (SEM). Degradation experiments of organic contaminant were also performed on samples of hollow spheres and walnut-like structures under visible-light illumination. Hollow sphere sample exhibited better photocatalytic capability than walnut-like sample. Possible mechanism was studied for WO3 center dot H2O assisted photocatalytic degradation of organic contaminant under visible light.