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Carbon nanotubes and carbon nanofibers as nano-materials and the combination of the carbon material, have many unique physical and chemical properties, are widely applied to a composite reinforced materials, adsorption materials, hydrogen storage material, a field emission material, catalyst and catalyst carrier, a lithium ion in many fields such as batteries, sensors, new blended material, muscle material and electron probe, with the deepening of the research work, the application of carbon nanotubes and carbon nanofibers prospects will be more broad. Common method for the preparation of carbon nanomaterials is still CVD, CVD method in recent years seen rapid development, and the catalyst is a key factor of carbon nanomaterials prepared by this method. Novel catalyst of the present in addition to the traditional unit Fe, Co, and Ni alloy catalyst, people are trying to study more efficient, such as the introduction of additives Synthesis polyhydric catalyst, etc., used to prepare the structure and morphology of the more perfect carbon material as well as more suitable for the respective practical application in the field of carbon nanomaterials. Hydrotalcite as a layered structure material, the metal cations on its shelves on the type and composition having an adjustable degeneration, and the metal ions in the laminates on distribution having the overall uniformity, thus using the the hydrotalcite precursor may be highly dispersed a metal ion can be obtained, after calcination, or restore the metal particles highly dispersed particle diameter is uniform. In this dissertation nucleation crystallization isolation method, the dynamic of urea prepared a series of different laminates cation of NiTi-LDHs, as well CuNiCrSn-LDHs, CuNiCrSn-LDHs after high temperature roasting to get CuNiCrSn-LDOs, the use of the proceeds of NiTi -LDHs and CuNiCrSn-LDOs respectively catalytic decomposition of the acetylene preparation different structure and morphology of carbon materials using XRD, TG-DTA and SEM to characterize it. Then electro-catalyst Pt / carbon material used in methanol electrocatalytic oxidation study investigated the electrocatalytic properties and anti-poisoning performance experiments prove its electrocatalytic activity and stability of the electrochemical deposition of the carbon material surface deposition of Pt preparation are higher than the Pt / C electrode commercialization. Situ growth of technology in the γ-Al2O3 surface preparation NiAl-LDHs/γ-Al2O3, and hydrotalcite direct decomposition of the growth of carbon material used in catalytic acetylene gas precursor different preparation methods, different Ni content and catalytic the grown carbon material time, the growth of carbon material structure, morphology and yield, and research in the NiAl system introduced Mg multivariate supported hydrotalcite structure of Cu metal elements such as preparation of the structure and morphology of carbon materials , and ultimately obtain the morphology of the carbon material of the carbon nanotubes and a spiral-shaped carbon fiber, etc., can be controlled by adjusting the type and composition of the metal in the catalyst precursor to the morphology of the resultant carbon material. XRD, SEM, TEM, HRTEM, Raman and TG-DTA analysis methods were used to characterize the resulting carbon material. And initially explore this supported catalyst can be reused, and the use of simple ultrasonic or stirring and other physical means separation of the resulting carbon material with the carrier, the catalyst component is still retained in the carrier can continue to be used for the catalytic growth of carbon material.
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