Preparation And Photocatalytic Properties Of Nano-titanium Dioxide Photocatalyst

In this article, The characteristic and classification of nanophase materials were discussed and the mechanism preparation and applications of nano-TiO2 photo-catalysts were also reviewed. We mainly studied the preparation of powers and film TiO2. XRD TEM AFM and UV-Vis instruments were used to characterize the samples. Photocatalytic decoloration and degradation of methyl orange(C14H14O3N3SNa) by merchantable TiO2 , powder TiO2 (we prepared in the lab) and film TiO2 were investigated. The research work of this article include the following aspects:The first part of the dissertation focuses on the characterization and classification of nanophase materials. The mechanism, preparation and applications of TiO2 in environmental purification,wastewater treatment,hygiene and anti-fogging etc were reviewed. The future prospect for the development of photocatalysis were also discussed. The modification and immobilization of photocatalysts and incorporation of multiform technique were probably the choice way to enhance photocatalysis efficiency.The second part of the dissertation deals with the application of merchantable TiO2 powers in the decoloration and degradation of methyl orange(C14H14O3N3SNa) . The TiO2 used in this paper was characterizedby XRD and the adsorption of TiO2 to UV light was also measured using UV-ViS photometer. The optimum experimental condition, which was that the amount of TiO2 was 2.5g/L and the initial concentration of methyl orange( Ci4Hi4O3N3SNa ) was 12.25mg/L , was concluded by researching the effect of the amount of TiO2 and the initial concentration of Ci4Hi4O3N3SNa on the decomposition rate of methyl orange (Ci4Hi4O3N3SNa). The photocatalytic activity of catalyst was improved dramatically when Ag was photo-reduced on the TiO2 surface or when H2O2 was added into the TiO2 powder suspension.The third part of the dissertation discusses the preparation of nano-TiO2 powers by hydrolysising with TiCl4 in weakly alkaline solution. After filtering, scouring, drying and burning, we can get TiO2 powers. The products were also characterized by UV-vis, XRD and TEM et al. Experimental results indicated that different burning temperatures influence the crystal type and particle size. We use TiO2 powers treated at different burning temperature (T=100-800 C) as photocatalysts, the photocatalysed efficiency of TiO2 diposed at 500 C is best. In the end, we compared the photocatalysed activity between merchantable TiO2 powers and those of we prepared. TiO2 powers we prepared showed better photocatalysed activity.The fourth part of the article described the preparation of TiO2 film.The nano- TiO2 photocatalysis film was prepared by Sol-Gel method using Ti(OC4H9) as predecessor and simple glass as substrates. The surface morphology , structure and composite were characterized by means of UV-ViS, AFM, XRD and XPS et al.The degradation efficiency of methyl orange was also good when we used the sample TiO2 film as catalyst. It maybe can solve the problems that photocatalysts were difficult to separation and recovery.