Paladugu Mohan Chand, Maneesh K, Nair P Kesavan, Haridoss Prathap
Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Madras, Chennai 600 036, India.
J Nanosci Nanotechnol. 2005 May;5(5):747-52. doi: 10.1166/jnn.2005.108.
In this work Carbon nanotubes have been synthesized by arc discharge in open air. A TIG welding ac/dc inverter was used as the power source for arc discharge. During each run of the arc discharge based synthesis, the anode was a low purity (approximately 85% C by weight) graphite rod. The effect of varying the atmosphere on the yield of soot of the carbon nanotube containing carbon soot has been studied. Various soots were produced, purified by oxidation and characterized to confirm formation of carbon nanotubes and their relative quality, using transmission electron microscopy, Raman spectroscopy, and XRD. It was found that the yield of soot formed on the cathode is higher when synthesis is carried out in open air than when carried out in a flowing argon atmosphere. When synthesized in open air, using a 7.2-mm-diameter graphite rod as anode, the yield of soot was around 50% by weight of the graphite consumed. Current and voltage for arcing were at identical starting values in all the experiments. This modified method does not require a controlled atmosphere as in the case of a conventional arc discharge method of synthesis and hence the cost of production may be reduced.
在这项工作中，碳纳米管是通过在露天环境下的电弧放电合成的。一台TIG焊接交直流逆变器被用作电弧放电的电源。在每次基于电弧放电的合成过程中，阳极是一根低纯度（按重量计约含85%碳）的石墨棒。研究了改变气氛对含碳纳米管的碳烟产率的影响。制备了各种碳烟，通过氧化进行纯化，并使用透射电子显微镜、拉曼光谱和X射线衍射对其进行表征，以确认碳纳米管的形成及其相对质量。结果发现，在露天环境下进行合成时，阴极上形成的碳烟产率高于在流动氩气气氛中进行合成时的产率。当在露天环境下使用直径为7.2毫米的石墨棒作为阳极进行合成时，碳烟产率约为消耗石墨重量的50%。在所有实验中，电弧放电的电流和电压起始值相同。这种改进的方法不像传统电弧放电合成方法那样需要控制气氛，因此可以降低生产成本。
