Abstract

The codoping of TiO2 provides a promising approach to extend the photo-response of TiO2 to the more abundant visible region and emerges as a very active research field in the photocatalytic degradation of organic pollutants very recently. The present review first gives an overview on the general performance of the co-doped TiO2 visible-light photocatalysts and then the current progresses in the synthetic methods and structure characteristics of the codoped TiO2 are summarized and discussed. The synergistic effects of co-doping on the optical absorption, the redox ability, the mobility and surface trapping of the photogenerated carriers are highlighted in the terms of the electronic, crystalline, and surface properties in the codoped TiO2, relative to the monodoped ones.