Preparation Of Carbon Nanotubes By Arc-Discharge And The Coating With Nanoparticles

Recently, more emphasis has been put on the study of the preparation and coatingof carbon nanotubes(CNTs) world-widely. Their cylinder shape, hollow tubulenanostructures, high thermal and chemical stabilities make CNTs a supporting rode inthe preparation of nanoparticles. Various nanoparticles have been attached to thesurface of CNTs by several methods. However, by far as we know, it is not reportedabout the coating nanoparticles by the microwave irradiation heating method.The following work has been done in this study:1. The Arc-discharge method of the CNTs was investigated. In experiment, theeffects were compared between the different atmospheres. The nano-scale catalyzerwas used to prepare CNTs. It was found that the output of CNTs in argon atmosphereis more than in helium atmosphere. The CNTs prepared by the nano-scale catalyzerhave less impurity than the CNTs prepared by other methods. It indicates that thenano-scale catalyzer works better. At last, we purified the prepared CNTs in the bestcondition.2. The CNTs were coated with ZnS nanoparticles using the microwave irradiationheating method. It is important to pretreat CNTs to change the surface condition ofthem. If not, the ZnS nanoparticles cannot attach to the surface of CNTs. The XRDspectra show that the crystal structure is different between the ZnS nanoparticles on thesurface of CNTs and the prepared ZnS nanoparticle without CNTs. It indicats that theCNTs not only acted as loaders but also could change the crystal structure of ZnSnanoparticles. 3. The CNTs were coated with flower-like ZnO nanoparticles by the microwaveirradiation heating method. The heterogeneity structure was obtained successfully. Itwas found that the pretreatment of the surface of CNTs is important too. If not, theflower-like ZnO nanoparticles can only nucleate in the solution. From UV-visabsorption spectra analysis. It was found that the ZnO-coated CNTs heterogeneitystructure shifts slightly to the red absorption range.4. The CNTs were coated by magnetic Ni nanoparticles using the microwaveirradiation heating method. In the process of attaching of Ni nanoparticles to thesurfaces of CNTs, the surfaces of CNTs was not only functionally pretreated but alsosensitized to activated afterwar. It indicats that the sensitizion and activation afterpretreatment are important. The difference ofthe magnetic propertiy between Ni-coatedCNTs and Ni nanoparticles without CNTs is investigated.