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TiO 2 nano-materials synthesis with controllable shape, is an important goal in the development of materials chemistry, because the material has superior performance in many fields, such as photocatalysis, dye-sensitized solar cells (DSSCs ) as well as bio-medicine and other fields. Therefore, studies on TiO 2 nano-materials, caused widespread concern. The morphology of the previous studies reported the synthesis of TiO 2 nano-materials, such as nanowires, nanorods, nanotubes, diamond-shaped ﹑ different polyhedral. In recent years, the synthesis has a hierarchical structure TiO 2 nanomaterials become a hot research at home and abroad. The structure is based on the smaller nanoparticles as building blocks assembled to give TiO 2 nanomaterials more advantages, such as large specific surface area, mesoporous it in photocatalysis, of DSSCs as well as bio-medical fields occupy a certain advantage, has potential applications. Therefore, to have a hierarchical structure of TiO 2 nano-materials synthesis research is important, and has a broad application space. In this thesis, the following research: (1), respectively, lauryl alcohol, aniline, azelaic acid as a substrate using sol - gel method and hydrothermal combined approach successfully synthesized TiO 2 microspheres and were characterized by SEM, HRTEM, XRD, BET and other means of testing. The results showed that: three kinds of TiO 2 of the diameter of the microspheres is between 500-700nm, they are assembled by a hierarchical structure having smaller particles of 13nm or so; its crystalline anatase phase, crystallization good degree; Moreover, three types of microspheres having a large specific surface area and rich mesoporous largest specific surface area of ??up to 101m2 / g, a pore size of about 9nm. Moreover, the formation mechanism of the mesoporous ball speculated that may be self-assembled by hydrogen bonds to form a spherical precursor, and then after the hydrothermal and calcined to remove the matrix, the hierarchical structure of mesoporous ball. (2) study the three TiO 2 photocatalytic properties of mesoporous microspheres as photoanode materials DSSCs of PV performance. Compared with commercial P25 powder, three TiO 2 mesoporous microspheres showed good photocatalytic properties and photovoltaic performance. Which, azelaic acid matrix synthesis TiO 2 best photocatalytic effect of mesoporous microspheres only need 5mg samples 40min can 25ml concentration of 20ppm solution of rhodamine B degradation completely; aniline as a substrate synthesis TiO 2 the mesoporous microspheres photovoltaic performance best photoelectric conversion efficiency of 6.55%. Moreover, we also from the perspective of the specific surface area, the optical properties and charge transport, the use of the amount of adsorption of the dye, the diffuse reflectance spectra and impedance spectroscopy analytical performance reasons for the differences. (3) using the emulsion polymerization method and dispersion polymerization, the regulation of the reaction conditions, was synthesized with different particle size of the PS ball. Sulfonated PS spheres the template successfully synthesized 2 _AT_ PS ball core-shell structure of the different particle size TiO dissolved, and then after the toluene treatment as well as high-temperature calcination, TiO2 hollow spheres of different size. Were characterized by TEM, XRD testing means. The results show that: the hollow sphere crystalline anatase phase, the shell is composed of smaller nanoparticles assembled. Experimental results, we found that the hierarchical structure of TiO2 nanomaterials does have a good photocatalytic and photovoltaic performance. Novel TiO2 nanomaterials provides a reference for the subsequent synthesis with high photocatalytic activity and photoelectric conversion efficiency. Moreover, according to the test results, these nanospheres with hierarchical structure in the biomedical field may have a good prospect of application.
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