Photodegradation of Pollutants in Water over TiO2 Supported on Molecular Sieves

Abstract

Dispersion of TiO2 on supported materials has been reported to be an effective approach to increase the catalytic activity of TiO2 in photodegradation of pollutants. Among the different supports, silica molecular sieves have the advantages of ordered porous structure, high surface area and high chemical stability. In this chapter, the preparation methods of TiO2 supporting on different types of silica-based molecular sieves and the resulting structures are demonstrated. The catalytic performances of these catalysts for photodegradation of organic pollutants in water are also discussed. The photocatalytic activity of supported TiO2 can be significantly enhanced by the molecular sieves as the supporting materials including zeolites, macro and mesoporous SiO2, and clays. The enhancement of the activity is mainly attributed to more active sites of TiO2 on the larger surface areas of the catalysts and the higher adsorption capabilities to organic molecules of the supported TiO2 in most of the cases. On the other hand, optimization of TiO2 loading, which in turn affecting the size of TiO2 particles, was found to be crucial to maximize the photocatalytic activity of the catalyst.