Preparation and Characterization of WO3 Nanocrystalline by Selected-dissolving of WO3/SiO2 Composites

Abstract

WO3/SiO2 was first synthesized by incorporating silicotungstic acid into amorphous SiO2 substrate via impregnation-sintering method. The nanocrystalline tungsten trioxide (WO3) particles were achieved through selected-dissolving as-prepared WO3/SiO2 composites in dilute fluoric acid solution. The crystallizing formation procedure of WO3 was monitored by BET and thermogravimetric-differential thermal analysis (TG-TGA), respectively. The resultant WO3 products were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results indicated the obtained particles belonged to the high pure orthorhombic phase, and possessed a small particle diameter and a narrow particle size distribution.