| Study on the light element materials becomes a sparkling topic material research in recent years, because light element atoms can be covalently bounded to each other and form stable compounds, which have variable contents, structures, and physical properties. In this thesis, we will focus on the nanotube structure and synthesis, including disorder multi-wall carbon nanotube, aligned multi-wall carbon nanotube array, CNX nanotube, and BCN nanotube. The effects of growth parameters, which provide scientific basis for pyrolysis of carbon nanotube, were studied systematically. Furthermore, layered aligned multi-wall carbon nanotube arrays separate by catalyst particles were synthesized on the surrounding of reaction quartz tube by injection of xylene-ferrocene for the first time, which provided a chance for the accurate measure and potential use of carbon nanotubes. Layered carbon nanotube with special length could be synthesized with this method. CNX nanotube and BCN nanotube were obtained with ethylenediamine as nitrogen source, and the growth parameters were screened at the same time. We found that the value of ID/IG, ID*/IG and FWMH of three bands could be used to estimate the degree of disorder. The field emission property of carbon nanotubes could be increased by substitution of nitrogen for some of carbon, however, however, that of BCN nanotubes was poor.1. Study of disordered multi-wall carbon nanotubeCarbon nanotubes with different diameter distributions have been produced by thermal decomposition of a ferrocene-xylene mixture under different temperatures and different catalysts in an Ar (or N2)/H2 atmosphere. The effect of the growth temperature, catalyst, and' the protection gases on the growth of carbon nanotubes were mainly studied with th help of TEM, SEM, and Raman spectroscopy. Carbon nanotubes with better quality and higher yield were synthesized at an appropriate temperature of 820C~860C and a catalyst of cobalt/ferrocene. There was no significant relation between the quality of carbon nanotube and protection gas. A new purified method for carbon nanotube was put forward.2. study of aligned multi-wall carbon nanotubeLayered multi-wall carbon nanotube arrays were synthesized firstly directly on the surrounding of the reaction quartz tube, in a Ar/H2 atmosphere by pyrolysis of ferrocene in xylene into a suitable reaction furnace with cobalt powder in. The effects of the growth temperature and duration on the growth of aligned carbon nanotube array were studied with the help of SEM and TEM. The experiments show that the reaction temperature significantly influenced the alignment of the MWNTs, and an appropriate reaction temperature for growth was 800C~900C. The diameter of the carbon nanotube increased a little with the growth temperature. Besides temperature, the reaction duration influenced the length of the well-aligned carbon nanotubes. There was no significant relation between the growth time and the diameter of the carbon nanotubes in the array. All of obtained array composed of many layers separated by catalyst particles. Those phenomenon may be due to non-uniform injection of feed. At last, a model of aligned carbon nanotube array were proposed.3. study of CNX nanotubeCNX nanotube were synthesis by thermal decomposition of ammonium chloride and ethylenediamine in an Na/Hfo atmosphere, respectively. We found that there is more "bamboo-shaped" in CNX nanotube made with ethylenediamine. The effect of growth temperature, catalyst, and content of ferrocene were studied systematically with the help of TEM. The "nanobelt" nanotube became to "bamboo-shaped" nanotube with the increase of growth temperature. CNX nanotube with higher concentration of nitrogen was obtained at 780C. The capability of catalyst following the sequence of Fe, Ni and Co. Ferrocene has key important role in the growth of CNX nanotube, especially with the help of cobalt. At the same time, Raman spectroscopy was used to studied the as-grown CNX nanotube. Besides the D band, both G band and D* band depend on...
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