Comparison of photocatalytic performance of anatase TiO2 prepared by low and high temperature route

Anatase TiO2 was prepared by a facile sol-gel method at low temperature through tailoring the pH of sol-gel without calcination. As a control, anatase TiO2 was also synthesized by the conventional sol-gel process, in which calcination at 500 °C was required to transform the amorphous oxide into highly crystalline anatase. As-prepared samples were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and photoluminescence spectroscopy (PL). Their photocatalytic activities were evaluated by degradation of methyl orange under UV light irradiation. On the basis of experiment results, it could be concluded that TiO2 prepared by low temperature route showed more advantages in small particle size, highly dispersion nature, abundance of surface hydroxyl groups, strong PL signal, and high photocatalytic activity over TiO2 obtained by the conventional sol-gel process. Furthermore, the reason of the former possessing higher photocatalytic activity was discussed.

Research highlights▶ Anatase TiO2 was prepared by low temperature (TiO2-120) and high temperature route (TiO2-500). ▶ Low temperature synthesis of anatase TiO2 is advantageous for energy saving. ▶ TiO2-120 showed more advantages in small particle and strong photoluminescence over TiO2-500. ▶ TiO2-120 showed higher photo-degradation activity of methyl orange than TiO2-500.