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Carbon nanofibers and carbon nanotubes have a unique structure and superior performance, prospects have applications in composite materials, catalyst carrier, hydrogen storage materials, sensors, fuel cells and capacitors. The synthesis of carbon nanomaterials by a kind of catalyst, carrier gas source, the reaction temperature and the co-catalyst, and many other factors influence different process conditions can be prepared by a different morphology of carbon nanomaterials. The Hydrotalcite a highly ordered two-dimensional layered structure of the material. Be applied to the preparation of carbon nanomaterials, on the one hand, the type and content of the active ingredient is adjustable changed, the controllability can be achieved on the preparation of carbon nanomaterials; the other hand, the active ingredient in the arrangement on the shelves uniform after firing has a high degree of dispersion, so that the nanocarbon material yield, structural regularity. In this paper, the advantages of these two aspects of the hydrotalcite as a catalyst precursor, CVD method under the process of synthesis of carbon nano-materials, combined with XRD, BET, TPR, XPS, SEM, TEM, HRTEM and RAMAN analysis means to obtain a series of regularity conclusions. , Respectively, using the impregnation method and the coprecipitation method to prepare the catalyst precursor in the preparation of a Pt-based catalyst carbon nanofibers. Dipping method, the calcined product of MgAl-LDH as a vector load Pt-based catalysts, the study found that the Mg content in the catalyst precursor increases to help to improve the dispersibility of Pt, and improve the yield and the degree of graphitization of the carbon nanofibers. Coprecipitation method, synthetic precursor different Pt content of a series of Pt / MgAl-LDH and its calcined product is a catalyst, Pt-CVD France under the synthesis of carbon nanofibers, the results show that: (1) the acetylene gas source Catalyst Synthesis carbon nanofibers optimum temperature of 600 ° C; (2) The catalyst content of the synthesis of the impact of the carbon nanofiber is large, the content is too low, the product yield is low, when the content is too high, particles are easy to aggregate, the appropriate choice of The catalyst content is very important. Combined the hydrotalcite interlayer anion exchangeable characteristics In Co base catalyst Preparation of carbon nanotubes, successfully cocatalyst W interpolation layer to the active component of Co-containing hydrotalcite precursor, and the integrated catalyst calcination The product was used for the preparation of the carbon nanotubes. The results show that adding a small amount of cocatalyst W is possible to improve the yield of carbon nanotubes, and to improve the morphology of the carbon nanotubes, and the cocatalyst W excessive, will cause large agglomeration of catalyst particles, thereby greatly reduce the yield of the product. rate.
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