Effective and efficient purification of single-wall carbon nanotubes based on hydrogen treatment

► We provide an effective and efficient method to get high-purity SWCNTs prepared by hydrogen arc discharge. ► Small SWCNTs can survive during the purification processes, and the purified SWCNTs possess high-crystallinity and escape obvious damage. ► A novel method used to prepare nanocatalyst (such as Pt, Pd and/or Rh) has been proposed.