Interaction Between Catalyst Metals and Stone-Wales Defects in Carbon Nanotubes

A Stone-Wales (SW) defect is a dipole of 5-7 ring pair in graphite networks. A SW defect has a strong effect on the mechanical properties of carbon nanotubes (CNTs), and is in fact one of most important defective structures in CNTs. Using first-principles methods, we calculated the interaction of SW defects with a series of foreign atoms that had been used as catalysts for the growth of CNTs, including Fe, Ni, Co, Ti, Cu, Al, Mg, and Mo. It was found that the adsorption of most of these foreign atoms at SW defects is energetically preferred when compared with a defect-free structure, and that transition metals generally have a strong attractive interaction with CNTs due to the unfilled 3d shells.