Research On The Synthesis And Growth Parameters Of Carbon Nanotubes By Plasma-enhanced Chemical Vapor Deposition

Carbon nanotubes (CNTs) can be thought of as a rolled-up sheet of hexagonal ordered two-dimensionality graphite formed to give a seamless cylinder. They can be from several to 100nm in diameter with lengths up to 100μm. Since carbon nanotubes have been discovered in 1991, they have become to be a focus of attention in nano-technology for their unique characters and special tube structure made of graphite flakes.There are some preparation methods, such as arc discharge, laser vaporization, chemical vapor deposition. The method of CVD is one of preparation technology and instrument equipment relatively simple and suitable for the great large-scale production, the apt method to realize industrialization. Plasma enhanced chemical vapor deposition developed from CVD, which can synthesize vertical aligned carbon nanotubes at low temperature, realized the controlled growth of carbon nanotubes. The key problem to prepare carbon nanotubes by PECVD is the catalyst. It can't produce carbon nanotubes without catalyst. At the same time, the other deposition parameters, such as the pretreatment of catalyst, the deposition temperature, the ratio between methane and hydrogen, the deposition time, are also very important. So, the key problems to produce high quality carbon nanotubes are catalyst and deposition parameters. This paper research on the preparation technology of carbon nanotubes with PECVD, and the preparation technology include the preparation of catalyst, the pretreatment of catalyst, and the growth of carbon nanotubes. To find the best technology conditions though experiment. We study the prepared carbon nanotube with Scanning Electronic Microscope (SEM) as well as Transmission Electron Microscope (HR-TEM) and Raman spectrum.The main experiments and conclusions are as follows:...