The Preparation Of The Carbon Nanotube By The CVD Using The Compound Nano Catalyst Synthesized Through Hydrothermal Method

The hydrothermal method was used to synthesized the transition metal nano compound powder with the hydrothermal precursor. And the precursor was prepared by Sol-Gel method using the TEOS (tetraethyl orthosilicate) and the transition metal nitrate (the nickel nitrate or the cobalt nitrate) as the material, ammonia or the sodium hydroxide as the precipitator. The transition metal nano compound powder were deoxidized by H₂, then catalyzed and cracked C₂H₂ to synthesize carbon nanotube. The transition metal nano compound powder and the carbon nanotuube were measured through the XRD, TEM, SEM and Raman. From those, the optimized conditions had been got to the preparation of the catalysts and the carbon nanotubes.1. The preparation of the catalysts by Sol-Gol-dydrothermal methodThe effect of the ratio of Si:Ni, different precipitator, PH, let old time, hydrothermal temperature and the let out time to the catalysts have been studied, including the phrase, the diameter, the crystallization and the activity of the catalysts.The results of TEM, SEM and XRD showed: the crystallization of the Ni(OH)₂/SiO₂ nano compound powder prepared by hydrothermal method was increased with the adding of Ni%'; the diameter were also increased with the rising of let out time, while the diameter of the catalysts first reduced finally increasing with the heightener of the PH Value; the diameter was larger using the the sodium hydroxide compare with the ammonia as the precipitator; rasing the let out time, the shape of Ni(OH)₂/SiO₂ was changed from acicular to sheet; different phase catalysts were produced different hydrothermal temperature; at 200℃ hydrothermal temperature, hydroxid compound powder were got from the nickel material while oxid compound powder from the cobalt material. 2. The preparation of the carbon nanotubesUsing the transition metal nano compound powder as the catalyst, the ethane as the reactive gas, the fine multi-wall carbon nanotubes were got by chemical vapor...