| Mesoporous materials become more and more important in the fabrication of nanodevices. By using the mesopores with controllable sizes as a nanoreactor, uniform nanoparticles and nanowires can be synthesized as nano-bulding blocks; the bulding blocks in mesopores possess long-range periodicity due to the ordered mesostructure of the template and the different morphologies of the host mesoporous materials can be used for various applications. The scientific issues of this degree thesis are based on the concept of synthesizing and assembling of nanostructures with mesoporous materials as hard templates. Firstly, mesoporous silica with monolithic morphorlogy was prepared and then the corresponding hard-templateing synthetic procedures of nanostructures were studied with alternative composites and various chemical pathways. The content of the thesis include synthesis and characteration of mesoporous materials and nanostructures, reaction mechanism research, and exploration of the electrical, optical and catalytic properties.In chapter 2, large-sized, crack-free silica monoliths with highly ordered mesostructure are prepared by a fast and easy way via liquid paraffin medium protected solvent evaporation. By employing the inert liquid paraffin as the morphology "protector", cracks of the materials can be successfully avoided and the processing time can be reduced from several months to 8 hours. In this way, silica monoliths with pure cubic mesostructures can be obtained at 90 癈.In chapter 3, a simple one-step synthetic route is described to prepare highly ordered mesoporous silica monolith with metal oxides nanocrystals in its channels. Highly ordered hexagonal silica monoliths with different metal oxide nanocrystals loaded, including Cr2O3, MnO,Fe2O3,Co3O4,NiO, CuO, ZnO, CdO, SnO2 and In2O3, can be obtained by this one step pathway. The nanocrystals of rod- or wire-like shapes are formed in the mesopore with the diameters of 5 ~ 8 nm. A one-step nanocasting route is employed and highly ordered cubic or hexagonal mesostructured In2O3 nanowire arrays were obtained. The materials are composed of single-crystals In2O3 nanowires with a diameter of 7 nm.In chapter 4, a fast and flexible one-step approach is developed to fabricate large-sized monolithic silica/block copolymer/metal sulfide composites with ordered mesostructure. Theoptical properties of the composites can be altered by varying the metal sulfides (ZnS, Co8S9, MnS, NiS, CdS, SnS, Sb2S3 and In2S3), changing the doped ratio and altering the composition of the ternary metal sulfides (such as CdxZn1-xS,). By using mesostructured SiO2/CdO nanocomposites as precursor, with the existence of S or Se sources, in situ hydrothermal phase transition reactions are employed for synthesizing CdS and CdSe nanocrystals under a reductive condition. Those CdS and CdSe nanoparticles are both 8 nm in diameter and highly crystallined with hexagonal lattices.In chapter 5, a one-step synthetic pathway is established for preparing polymer nanostructures. The polystyrene and polyacrylic acid nanoparticles with ultra-small sizes were obtained. The spherical nanoparticles are quite uniform with diameters of 2~4 nm. Employing polyacrylic acid nanoparticles as a hard template, polyacrylic acid/semiconductive metal sulfides(CdS and ZnS) core/shell nanoparticles are derived, and the diameter of the nanoparticles are in the range of5~8 nmoIn ordered to introduce the concept of molecular design in the hard-templating synthesis of polymer nanostructures, density function theoretical computation are carried out for the complicated organic-organic interaction in the synthetic system of polymer nanostructures. In chapeter 6, via the computation of geometry, electron structures and thermodynamic parameters, the assembly process based on organic-organic alteration are specifically described, and serial reaction principles are speculated. Porper organic monomers are selected with those principles and corresponding polymer nanaoparticles are prepared.In chapeter 7, by using mesoporous silic...
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