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Nanoparticles of uniform size because of its important uses and is widely studied, and the size of the nanoparticles control monodisperse nature and applied research for which has important significance. Solvothermal method, as in the presence of a surfactant reducing metal, synthetic uniform size monodisperse metal nanoparticles main way. This approach utilizes ligand in solution, the molar ratio of the reactants, the reaction temperature and time parameters adjusted to control the size of the nanoparticles. Monodisperse magnetic nanoparticles in catalysis, ferrofluids, magnetic refrigeration systems, drug delivery and magnetic conductivity such as high-density information storage has wide application. To date, many of monodisperse magnetic nanoparticles such as metals (nickel, diamonds, gold, platinum, palladium, etc.), metal oxides (iron oxide, iron oxide, manganese oxide, manganese tetroxide, etc.), mixed oxides ( cobalt ferrite) and alloys (cobalt-platinum) solvothermal synthesis and properties have been studied in depth. Which have a uniform size of monodisperse nanoparticles and nickel nanorods have been synthesized, but the use of nickel precursor, and the synthesis system is very complex, and the inorganic reducing agent (such as NaBH4), easy to introduce the system of impurities. This topic simplified solution system, safety and low toxicity of the metal salt precursor to control the reaction conditions are different sizes of monodisperse metallic nickel and palladium nanoparticles. 1. Preparation of nickel acetate as a precursor of Ni nanoparticles Monodisperse the subject of the use relatively simple single surfactant system wherein the surfactant hexadecylamine, both as a solvent and as a reducing agent and a stabilizing agent, the reaction system greatly simplifies . Reaction precursor anhydrous nickel acetate, compared with previous literature using organic salts, nickel acetate cheap and readily available, low toxicity and stability. Reaction in N 2 atmosphere by controlling the reaction conditions are slowly heated different polymorphs, different sizes of nearly monodisperse nanoparticles of elemental Ni, particle dispersion, uniform size. This study investigated the reaction temperature, reaction time and the molar ratio of reactants on the product size, dispersion and crystalline form, and its formation mechanism was discussed on the metal Ni nanoparticles were TEM, HR-TEM, XRD, TG, IR, SQUID were characterized. 2. As a precursor of palladium chloride was prepared nearly monodisperse nanoparticles of metal Pd hexadecylamine system used in this experiment, the use of water as an inorganic precursor of palladium chloride, under different reaction conditions in monodisperse nanoparticles of Pd metal were studied . Way through the slow heating of the different particle sizes obtained by the reaction of nearly monodisperse nanoparticles of metal Pd, and the resulting particle size uniformity, better dispersion. It was found that: changing the temperature, the molar ratio of the reactants, reaction time and other parameters can change the particle size. Wherein the reaction time of a change of the morphology of the larger product. Also found that the reaction product of an atmosphere also has a greater dimension morphology influence. In this thesis, palladium nanoparticles were TEM, HR-TEM, XRD, TG, IR, SQUID, and pore size distribution and specific surface area were characterized.
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