Preparation Of Carbon Nanomaterials By Arc-discharge Plasma Jet

Theoretic prognostication and researching work show that the carbon nanotubes (CNTs) have characteristics in mechanism and electrology and calorifics which make them great application in these fields. The unsettled problems in synthesizing high quality CNTs and purifying the CNTs baffle the researching work. So studying of synthesizing high quality CNTs becomes even important.Apparatus of arc-discharge plasma jet method are used in this paper. Many experiments are carried out by this method. The experiment samples were characterized using Energy Dispersive X-ray detector (EDX), Scanning Electron Microscope (SEM) and Transmitting Electron Microscope (TEM). The result comes out that it is possible to produce carbon nanomaterials from raw coals, coal liquefaction residues (CLR) and ethanol.Carbon nanomaterials can be produced from raw coals, without any pretreatment by arc-discharge plasma jet under atmospheric pressure. When Fe is added as catalyst and water as additive, the yield of CNTs increased evidently. The effects of catalyst and additive are addressed in detail.Multi-wall carbon nanotubes have been successfully synthesized under arc-discharge plasma jet conditions from CLR which were produced as by-products in the process of coal liquefaction without any pretreatment or adding any other additional catalysts. We found that the experience lasting time is a crucial factor for the formation of carbon nano fiber (CNFs) inthe present work.Bamboo-shaped CNTs were synthesized continuously in high yields from ethanol with ferrocene(C₅H₅)₂Fe been used as catalyst precursor in arc-discharge plasma jet under atmospheric pressure. It has been found that the CNTs exist in entangled state and the content of bamboo-shaped CNTs in the products is estimated to be over 90%. Bamboo-shaped CNTs with branched morphologies are also obtained under the experimental conditions. Fishbone-type stacking of graphene sheets in the wall of bamboo-shaped CNTs has been observed. When ammonia, Cu(NO₃)₂ and ferrocene was added in ethanol, a special morphology carbon nanomaterial is produced. The growth mechanism of the bamboo-shaped CNTs and the special morphology carbon nanomaterial is discussed.