Length-controlled synthesis of single-walled carbon nanotubes by arc discharge with variable cathode diameters

► SWNTs purity and the crystallinity of SWNTs can be improved by using appropriate cathode. ► Length-controlled synthesis of SWNTs has been achieved by changing the cathode diameter. ► The differences in nucleation/growth processes lead to the changes in SWNT diameter distribution. ► Plasma densities and temperature distributions influence SWNT nucleation and growth processes.