Doped-metal oxide nanoparticles for use as photocatalysts

Nano-sized doped-metal oxides such as Fe-doped TiO2, WO3-doped ZnO and Fe-doped CeO2 were synthesized by the modified sol-gel/impregnation, flame spray pyrolysis and homogeneous precipitation/impregnation methods respectively. The crystalline phase, particles size, and crystallinity of nano-sized powder were analyzed by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Specific surface area of the sample was examined by the Brunauer, Emmett and Teller (BET) adsorption–desorption of nitrogen gas. The photocatalytic activity of Fe-doped TiO2, WO3/ZnO, Fe-doped CeO2 nanoparticles was examined by studying the mineralization of methanol, sucrose, glucose, oxalic acid and formic acid under UV and visible light irradiations in a pyrex spiral photoreactor. It was found that doped metal oxides could improve the photocatalytic activity of the pure metal oxides.