An efficient method to produce single-walled carbon nanotubes by round-trip arc discharge

By using a tungsten rod as cathode and exchanging the electrodes after each discharge, large amount of single-walled carbon nanotubes (SWCNTs) were produced by an improved arc discharge method, in which the Y–Ni–C composite rod was used as anode. The raw SWCNTs were characterized by HRTEM and Raman spectroscopy and the results show that the SWCNTs produced in this way have the same structure as the others. Moreover, the efficiency of the anode was enhanced greatly (more than 90 wt.%) and about 10 g soot could be obtained after the discharge.