| The usage of nano-materials are strongly influenced by their property such as chemical composition, morphology, structure, size, configuration and arrangement, as a result of that, the effective control on these property are especially important to the research on the preparation methods of nano-materials. Template method is preferable to other methods for the preparation of nano-materials, with which the morphology, size, structure and arrangement of nano-materials can be controlled effectively by selecting templates with appropriated confined space and oriented function. Therefore, preparation of nano-materials by template method is a hot topic in materials science and gains much attention during recent years. This paper is focused on the application of polycation and emulsions as templates on the preparation of nano-materials, a series of materials with hollow or porous structure are prepared by using them as templates. The main content is listed as following:1. In Chapterâ…¡, Poly (2-(diethylamino) ethyl methacrylate) (PDEA) (the precursor of cross-linked polycation) latex with novel pH-responsive behavior were prepared directly by radiation-induced dispersion polymerization; Manganese oxide hollow spheres were prepared in acid solutions by using pH-responsive latex as templates. The influence factor such as the constitution of dispersed medium, the dosage of stabilizer and the cross-linker on the size and size distribution of latex were studied thoroughly; the pH-responsive behavior of PDEA latex was also studied by several methods, and the results indicated some PDEA latex had irreversible swelling-to- deswelling transition; The shell thickness of manganese oxide hollow spheres was found increased with the dosage of KMnO4, which implies a controllable and feasible strategy for manganese oxide hollow spheres preparation has been established; finally, a probable formation mechanism for the hollow spheres was proposed.2. In Chapter III, Hexadecylamine (HEX), Poly (vinylpyrrolidone) (PVP) and Poly (2-(diethylamino) ethyl methacrylate) (PDEA) (the precursor of lined polycation) homo-polymer were used as templates for the preparation of porous nano-material. The different protonated extent was believed as the main reason for their different performance. The highly protonated PDEA polymer solution is proved outstanding on the preparation of manganese oxide materials with narrow pore size distribution and high surface area, and the morphology of manganese oxide was follower-like aggregates which constituted by flakes with a lot of meso-pores. Besides, the results confirmed these organic templates involving with reduction of inorganic precursor. The morphology of nano-materials were found changing with the addition dosage of inorganic precursor to organic templates, and they all existed as thick plates-like when the dosage of inorganic precursor getting certain value. All the results indicated the structure of products can be effectively controlled by the selection on organic-electrolyte and their protonated extent. Besides, the catalyzed experiments on oxidation of indene or benzyl alcohol proved that the resulted manganese oxide products can be the good catalysts.3. In Chapter IV, Hollow magnetic OA-nano-Co3O4/polystyrene composite spheres were prepared by using emulsion as templates. The influence factor such as the addition dosage of nano-particles and sodium dodecyl sulfate on the size and size distribution of hollow spheres were thoroughly studied. The nano-Co3O4 particles were proved to inhibit the polymerization process. After tracking on the structures of products at each selected polymerized time, pores are found accompanied with hollow structure. A probable mechanism for the hollow spheres formation was proposed, and the key factor to the formation of hollow structure is the possibility of styrene monomer come together with free radicals produced by radiolysis of water at the oil/water interface. The magnetic properties of these hollow composites were studied finally.4. In Chapter V, the morphology of products by using confined space (W/O type) and unlimited space (O/W type) emulsion as templates were compared. The results showed the effectively controlling on the morphology only obtained when the inorganic precursor existed in confined space. Meso-pores were found on the concaved cuboctahedrons appearance products after heat treatment.
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