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The doctoral thesis on the basis of previous research, plating and liquid phase reduction method, Nickel Cobalt 1-x-x-P / multi-walled carbon nanotubes (Ni1-xCox/MWNTs), nickel - cobalt were prepared - phosphorus / silicon carbide (Ni-Co-P/SiC), nickel / the chemical conversion graphene (Ni / CCG), platinum / chemical conversion graphene (Pt / CCG), platinum / multi-walled carbon nanotubes (Pt / MWNTs ) Five new nano materials; using a scanning electron microscope (SEM), transmission electron microscopy (TEM) to study the morphology of these materials: X-ray powder diffraction analyzer (XRD), X ray photoelectron spectroscopy (XPS), X ray energy dispersive spectroscopy (EDX) analysis of the lattice structure of these materials and elements; using a vibrating sample magnetometer strong count (VSM), vector network analyzer analyzes Ni1-xCoxP/MWNTs Ni-Co-P/SiC and Ni / CCG magnetic, absorbing nature; electrochemical method to study the Pt / CCG, Pt / MWNTs as the catalytic performance of the direct methanol fuel cell. The study mainly include: 1. Multiwalled carbon nanotubes boiling with concentrated nitric acid, SnCl2, PdCl2 solution sensitized activation solution, from the distribution of chemical plating Ni-Co (Ni: Co = 1:3,1:1 3:1) plating, obtained Ni1-xCoxP/MWNTs composite material (x = 0.75,0.50,0.25 the Ni1-xCoxP particle size distribution of 8-18nm). The XRD data shows MWNTs composites the Ni1-xCoxP nanoparticles having a lattice structure, after heat treatment after dispersion of the outer wall of MWNTs irregular dot-like structures. The measurement results of the magnetic properties of the sample that reduced the coercive force and the magnetization of the material prepared as the Ni content increases. Complex permittivity values ??within the frequency range of 2-18GHz Ni1-xCoxP/MWNTs- paraffin mixture is reduced as the Ni content increases; only a slight increase of the complex permeability. With the decrease of the Ni content, the peak electromagnetic wave reflection loss of the prepared material is moved to the low-frequency region, and when x = 0.75, and the matching thickness is 2.5mm, in the 7.75 GHz at the maximum reflection loss of-26.84dB. 2 using a two-step activation method of chemical plating techniques, into the solution of the Ni-Co from the distribution of SiC in the Pd activation Shi the plating obtained Ni-Co-P/SiC composite material. The morphology and structure of the proof of the particles of the Ni-Co-P and good uniformity, and after the heat treatment by the α-Co and Ni3P. Magnetic properties of analysis and microwave absorption test results show Ni-Co-P/SiC a saturation magnetization and the coercive force is relatively low, and having a higher dielectric constant value, the magnetic loss material of the microwave absorption properties also have a certain contribution. An electromagnetic wave reflection loss measurement results show that when the starting solution, the atomic ratio of Ni-Co is 1.5, the maximum reflection loss value is-32dB, the matching thickness of 2.5mm, the frequency of 6.30GHz. Using hydrazine hydrate reduction method, NiSO4, graphite oxide (Graphite Oxide, GO), respectively, as the Ni and the source of the carbonaceous support, preparation of Ni / joins CCG composites. The magnetic properties of the analysis showed that the prepared Ni / CCG showing ferromagnetic nature, is expected to be applied in absorbing materials, magnetic recording field. The oxidation of the graphite powder into GO, and then restored in the chloroplatinic acid - ethylene glycol - aqueous systems, Pt / CCG composites; MWCNT for processing in a similar manner to obtain Pt / MWCNT composite material. And contrast these two materials as the catalytic performance of direct methanol fuel cells, electrochemical active surface area of ??the Pt / CCG and Pt / MWCNT 36.27m2 / g and 33.43m2 / g, respectively. Pt / CCG with more the CO poisoning endurance, activity shows enhanced electro-catalytic oxidation of methanol.
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