| Nanometer-sized TiO2 has many unique physical and chemical properties. It is used extensively in many fields, such as dope, paper-making, printing, chemical fiber, cosmetics, catalysts, antimicrobial and disposal of waste water. Because of safety and energy saving, nanometer-sized TiO2 is regarded as one of the most useful materials in catalyst fields.At present, the photocatalysis systems of nanometer-sized TiO2 mainly consist of powder-suspended system and coated-photocatalysis system. But the nano-powder is not suitable to be reclaimed and segregated and therefore is far away from the application in large-scale at the moment. To conquer these difficulties, coated nanometer-sized TiO2 can be used. Core-shell style nanometer-sized TiO2 does not have these shortcomings. One of its important extended uses is to get a hollow sphere by removing the core when heated or dissolved. This hollow sphere has low density, special polarity and optical property. The aim of this thesis is to fabricate nanostructure TiO2 and hollow sphere by combining the sol-gel technology and layer by layer self-assembly method. At the same time the mechanism of the self-assembly is studied. The major work includes the following aspects:1. Sol-gel technology and layer by layer self-assembly methods is utilized, with Ti(OC4H9)4 and C2H5OH as the raw material, 12 alkyl sodium sulphate (C12H24SO4Na) aqueous solution serving as organic self-assembly monolayer. Different layer numbers, different contents and different surface structures nanometer titanium dioxide have been successfully assembled on the Al2O3 surface. The influence of different experimental conditions on the preparation is studied.2. 12 alkyl sodium sulphate (Ci2H24SO4Na) aqueous solution serving as self-assembly medium, we investigate the mechanism of self-assembly by measuring the absorption isotherm, Zeta potential, contact angle, and spectrum of IR. It shows that r -Al2O3 has positive electricity on its surface and can form a single-molecule-layer absorption withC12H24SO4Na. By means of the absorption of the organic chain of two C12H24SO4Namolecules then it will be a double-molecule-layer absorption and form a half-micelle absorption. In this structure the polar group is towards outside so it carries negative electricity on the surface and it can absorb the particle in the sol which carries positive electricity. In this way the nanometer particle TiO2 can be assembled on the surface of the r -Al2O3. The investigation of the mechanism of self-assembly will give us a direction for the study of optimizing the preparing conditions and the control of the reaction process.3. Utilizing Ti(OC4H9)4 and low-cost TiCl4 as raw materials, a certain substance as solvent, C12H24SO4Na as self-assembly medium we have prepared nanostructure TiO2 successfully on the surface of Pst microball whose diameter is about 0.25mm in different conditions, such as temperature, acidity, and laid time etc. Then we have prepared hollow-sphere which has different contents, different structures, different features and crystal forms by controlling the temperature-changing ratios and the calcination temperatures.4. All of the above samples have been characterized by XRD, SEM, X-ray energy spectrum, IR, TG-DTA and titanium method etc. The research results show: ã•he self-assembly medium can influence the microenvironment of the carrier surface and the absorption content. The absorption state of the carrier surface can be controlled by altering the self-assembly medium concentration and the alternation also lead to the change of the electric property of the carrier surface. (2) Controlling different conditions of the acidity, temperature, reaction time, calcination temperature we can prepare different crystal forms, different features nanostructure TiO2 and hollow ball. (3) With the increase of the number of the layers, the content of titanium dioxide increases in basic line and the carrier surface becomes fine and compact.5. Photocatalytic activity of nanostructure TiO2 has been studied by...
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