| Fuel cells are a kind of high efficient and green power source. One of them, the fuel utilizing methanol as the anode has many merits, such as it operate at low temperature, weight light and has high power density and current density, so it can be used in aviation, submarine, automotive and portable. One of the major problems of the methanol fuel cell is the sluggish methanol oxidation kinetics at anode. Transition metal Pt and its alloys, oxides are the common oxidation catalysts for organic molecules including methanol for the dehydrogenation reaction. So they are also the good catalysts for the anode of methanol fuel cell. The catalytic activity of the catalyst is influenced by the size, shape and distribution of the catalyst particles. So preparing small size and homogeneous distribution catalyst nanoparticles are very important. Electrochemical supercapacitor is a new type of energy storage device, These materials include conducting transition metal oxides and conducting polymers are studied for the application of electrode, and the specific capacitance of the materials is important for the supercapacitor.The first part of this dissertation is a review which focuses on the special preparation methods, characterization, and application of the nanometer metal catalysts. The second part deals with the preparations of PtNi/C, Pt/C, Ru/C na noparticles as well as the structure characterization of the samples by XRD, T EM, EDX. Electrochemcial tests characterized the electrocatalytic activity of Pt Ni/C and Pt/C for the methanol and the specific capacitance of Ru/C when the y are used as anode material of electrochemical supercapacitor.In ethylene glycol solution, by adding NaOH to adjust the initial pH of the reaction solution, we synthesized PtNi/C catalysts with the size can be control. The structure of the samples were characterized by XRD, TEM, EDX and the results indicated that in the ethylene glycol process, the pH of reaction solution had effect on the PtNi particles size and distribution. The electrochemical tests proved that their activity of the alloying catalysts for methanol oxidation at anode increased with the reducing of the size of the PtNi/C catalysts.In ethylene glycol solution, using sodium acetate as stabilizer we prepared high dispersion 20% Pt/C, then we prepared high dispersion and high loaded 40% Pt/C nanocatalysts. The structures characterization showed that when the ratio of the atoms of acetate and Pt was 5, the Pt nanoparticls had the size of 3.0 nm or so. The electrochemical tests proved that the Pt/C naoncatalysts have good activity for methanol oxidation at anode.In ethylene glycol solution, we direct synthesized different loadings Ru/C nanoparticles(10%, 20%. 40%, 60%) without adding any stabilizer such as pvp et. By the characterization of their structures, we discovered that their size was small at 2.8 nm or so and the size distribution was homogeneous. In the react, ethylene glycol was used as solvent, reduce agent and stabilizer. Through electrochemical tests we found that they had high specific capacitance when they were used as anode materials in supercapacitor.
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