The preparation of carbon nanotubes by DC arc discharge process using Xylene-Ferrocene as a floating ctalyst presusor

A new synthesizing method, a floating catalyst technique, was studied to produce carbon nanotubes in a dc arc discharge process. The Xylene-Ferrocene (catalyst precursor) was directly introduced into the DC arc chamber by carrying gas. Experimental results showed that multi-walled carbon nanotubes (MWNTs) and single-walled carbon nanotubes (SWNTs) can both be synthesized using this technique. The quantity of synthesized MWNTs and SWNTs varied depending on the process conditions, such as the flow rate of ferrocene, pressure, process current and voltage. The yield of SWNTs was improved by increasing the flow rate of Xylene-Ferrocene due to the high density of the catalyst precursor but decreased by lowering process current due to poor activation ability of catalyst.