| As the most important issues, energy shortage and environmental pollution have attracted much attention all over the world. In some extent, the urgency to solve these problems accelerates the development of catalytic materials. Due to its chemical stability, non-toxic, strong oxidation, anti-corrosion and low cost, TiO2 has been used as an important photocatalytic material and made a great progress. However, since the band gap of TiO2 is 3.2eV, only the UV-5% of the sunlight can be efficient, it is necessary to make a red shift of absorption edge of TiO2 to improve its efficiency.In this paper, we improved the TiO2 photocatalytic activity in two aspects of preparation method and N,S co-doping. The main research and experiment results were as follows:1. The mesoporous N, S-TiO2 powders were synthesized by a simple hydrothermal method, and the preparation technology such as amount of hydrothermal temperature, thiourea doped amount, calcination temperature of preparation were studied. The results showed that the mesoporous structure was due to the aggregation of a large number of nano-particles, and preparation technology also affected the microstructure, crystal phase, photocatalytic properties, and so on.2. By means of SEM, XRD, BET, XPS, and UV-Vis, the co-doping of N,S was favorable to the formation of anatase, and increaseed the surface area. The BJH curve further confirmed the existence of mesoporous structure.3. With the XPS test, N, S elements were present in the TiO2 powder. S element was mainly adsorbed on the crystal surface in the form of SO42-, the N element replaced O in the lattice or chemically absorbed on the surface. These two elements of the doping improved the utilization of visible light.4. According to UV-Vis and photocatalytic degradation, N, S doped samples had more absorption to visible light, and their degradation of methylene blue capacity in the visible light were significantly stronger than the undoped samples and commercial Degussa P25. |
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