UV/ozone-assisted low temperature preparation of mesoporous TiO2 with tunable phase composition and enhanced solar light photocatalytic activity

Abstract

In this paper, we report a UV/ozone-assisted method for low temperature preparation of mesoporous TiO₂ with controlled crystalline phase. The results showed that the crystallization of mesoporous TiO₂ can occur at temperatures as low as 100 °C under UV/ozone irradiation. Highly crystalline mesoporous anatase TiO₂ was obtained after UV/ozone treatment at 200 °C. The phase transformation from anatase to rutile occurred during the UV/ozone treatment at 300 °C and mesoporous bicrystalline TiO₂ with a controlled mixture of anatase and rutile phases was prepared by adjusting the exposure time. The photocatalytic performance of the mesoporous TiO₂ strongly depends on the crystal structures and the bicrystalline mesoporous TiO₂ exhibits remarkably enhanced solar light photocatalytic activity. This technique can be useful for low temperature preparation of crystalline mesoporous titania on various substrates and may be generalized to the synthesis of other materials.