The Preparation And Adsorption Properties Of Carbon Nanotubes

Because unique performance of carbon nanotube in mechanical and electrical, chemical, etc, it has potentials to widely applied to nanoelectronics, electronic field-emission, sensors, STM probe, adsorption, catalytic and other fields. Research personnel of all over the world give a great attention to it. Among them the relevant adsorptive characteristics of carbon nanotubes research by fervent attention in recent years. Carbon nanotubes adsorptive characteristics of further research become inevitable development of science and technology. This will make a significant contribution to carbon nanotubes the more widely used in adsorptive field.In order to make the carbon nanotubes in the future to better application, this paper used chemical vapor deposition (CVD) method of preparation of various types of carbon nanotubes. And through the high resolution electron microscopy (HRTEM), scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), thermal heavy - differential thermal analysis (TG-DAT), Raman spectroscopy analysis (Raman) instruments and analysis methods studied material structure, the electrical, optical etc, characteristics of the different types of carbon nanotubes. And had done model prediction and experiment about the carbon nanotubes may growth mechanism and characteristics which grew in different circumstances. In addition, adsorption characteristics about nitrogen at 77K temperature of brought Muti-walled carbon(MWNT) nanotubes and activated samples have been investigated and compared. Draw following conclusions:1. Adopt MgO style carrier low-pressure CVD method can be preparation of large-scale, cheap, efficient carbon nanotubes. The results of the analysis which had obtained by XRD, SEM, HRTEM, Raman, poor heat and thermogravimetric analysis about the various types of purified carbon nanotubes topography, structure show that deposition temperature and carbon source and carrier catalytic particles concentration, grain scale are critical factors to effect carbon nanotubes'growth structure. When preparation of single-walled carbon nanotubes should be used the gases source of less carbon. The carrier and the nano catalysts mole ratio of less than 0.9 : 0.1. And the best deposition temperature should be in 850～9.5℃. However, when grow Multi-walled carbon nanotubes should be used the gases source of more carbon and nano catalyst carrier of high content. Meanwhile choose higher deposition temperature. 2. The results of the analysis which had obtained by TEM,SEM,ASAP 2405N analyzer about the morphology, structure and adsorption properties and comparative analysis of brought MWNT and activated samples indicate that the specific surface area of the active carbon samples is larger. While, the pore size and total pore volume of the MWNT samples are larger. Activated carbon's adsorption capability is better than that of MWNTs at low relative pressure. But when the relative pressure pass 0.9, MWNTs samples adsorption capabilities is shown better and goes beyond that of active carbon. At the same time, the desorption capability of MWNTs is more favorable than that of active carbon at high pressure.