Synthesis Of Nano-Sized Titanium Dioxide Doped With Cations And Anions And Study On Its Photocatalystic Activity

Nano-meter photocatalysts have drawn much research attention in recent years due to their applications to environmental purification. TiO2 has been proved to be an excellent catalyst in the photocatalytic degradation of organic pollutants, because it is an effective, photostable, inexpensive, non-toxic and easily available. However, Most investigations have to be carried out under ultraviolet (UV) light, because TiO2 photocatalyst shows relatively high activity and chemical stability only under UV light,which limits its application in the sunlight. In addition, higher electron-hole recombination rate and short lifetime also inhibit its extensive application. Therefore, how to improve the photocatalystic ability of the TiO2 is what we need to resolve.Referring to the previous works, introducing doping ions in TiO2 is known as an effective method by which its photocatalystic ability can be improved. Therefore in the thesis, the TiO2 doped with various ions have been synthesized through both a low temperature molten salt and hydrothermal method, respectively; and their performance in the photocatalystic activity and photooxidation rate has been also rated.1. Nano-sized SnxTi1-xO2 photocatalysts were successfully synthesized by a molten salt (MS) method at a low reaction temperature, where homogeneous precipitates containing titanium and tin cations were used as precursors. The synthesized powders have been investigated by using such a testing technique as TG-DTA, XRD, TEM and UV-VIS, respectively. The results showed that the nano-sized Sn0.25Ti0.75O2 photocatalysts, which are composed of homogeneously...