Recent Advancements in Doped Titanium Dioxide (TiO2) Nanostructures for Photocatalytic Dye Degradation

Titanium dioxide (TiO2) and doped TiO2 have emerged as efficient photocatalytic materials for the degradation of harmful dyes released in water. The doping significantly increases the photocatalytic activity of TiO2 by enhancing light absorption in visible region and by alteration of structure, surface area and morphology etc. The doping of TiO2 has been achieved with various elements from the transition metal series, ions, nitrogen, with rare earths and other metallic nanostructures. Recently, significant new developments were noticed in the literature about doping of TiO2 with new materials using different strategies. In this review, the basic information of TiO2 as a photocatalyst is presented and the importance of doping to improve the photocatalytic performance of TiO2 is highlighted. Recent reports about the doped TiO2 from the literature are listed in tabular format and critically analyzed. The collective information presented will help to design new doping strategies and to come up with novel and more efficient TiO2 based photocatalysts to develop a water purification technology.