Catalysts effects on the production of carbon nanotubes by an automatic arc discharge set up in solution

Abstract Carbon nanotubes (CNTs) represent an important group of nanomaterials with attractive geometrical, electrical and chemical properties and are synthesized using a variety of techniques. CNTs have been extensively studied in our previous works and in this study were fabricated by arc discharge full automatic set up in liquid which does not require vacuum equipment, heat exchange system, active or inert gases. This technique was full automatic which enabled the controlling of gap between the two electrodes. The effect of the kind of catalyst on quantity of synthesized CNTs was studied herein. Carbon nanotubes were fabricated between two graphite electrodes which were submerged in the LiCl 0.25N as a solution and with a voltage of 25v. For comparative studies, Ni, Mo, Fe and Ni‐Mo were exploited as metallic or bimetallic catalysts and the results were subsequently analyzed, compared and discussed. In order to analyze the morphology of the synthesized products a scanning electron microscopy (SEM) as well as transmission electron microscopy (TEM) study were employed. Based on Mo‐Ni as catalysts in carbon electrode, high‐crystalline and alonged multi walled carbon nanotubes (MWCNTs), single walled carbon nanotubes (SWCNTs) and spring‐like carbon nanotubes (SCNTs) were synthesized by using this unique technique. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)