| Nowadays, the problems of environment have become server and server, which have had obvious negative effects on our health and daily lives. How to clean the pollution is one of the big challenges in the world. Heterogeneous photocatalysis is an attractive technique because it is an energy-saving and economical method. Many photocatalysts can be used, and TiO2 is one of the best due to its stability and non-toxicity. The disadvantage of TiO2 is its wide bandgap, which limits its large-scale application in reality, so how to use visible light is still an increasing hotspot up to now.In this research, the method of hydrothermal was used to prepared Fe doped TiO2 and F surface-modified TiO2. We studied the structure and photocatalytic activities in detail, and the relation between structure and activities were also analyzed.(1)Fe-doped TiO2 nano photocatalysts were fabricated using hydrothermal method. The as-prepared samples are composed of small and uniform anatase TiO2 nanopartilces. The absorption edge of the Fe doped TiO2 has a red shift and the sample also has a stronger absorption than the pure TiO2 in visible region. The Fe doped TiO2 shows increased photocatalytic activity when<0.8 at.% ions were introduced.(2)Surface-fluorinated TiO2 nano-photocatalysts were prepared using hydrothermal process. The amount of HF has significant effect on the crystallite of the TiO2 photocatalyst. The fluorinated TiO2 after sinter is slightly higher than of the pure TiO2 sample at<500nm, whereas the absorption edge region is almost unaffected by the surface fluorination, This also confirms that F element do not enter the lattice of TiO2. The photocatalytic activity of sintered samples is better than that of pure TiO2 because the electron-hole recombination is inhibited due to surface anchored F ions. |
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