Controlled sliding and pullout of nested shells in individual multiwalled carbon nanotubes

A mechanical-loading stage operating inside a scanning electron microscopy (SEM) was used to realize the sliding between nested shells of multiwalled carbon nanotubes (MWCNTs). A stick-slip motion and a smooth pullout motion were observed for the two separate MWCNTs studied. A model that includes th e shear interaction, the "capillary" effect, and the edge effect, was used to explain the observed sliding between nested shells. The shear strength b etween shells was determined and the surface energy of the MWCNT shell esti mated.