Atomic-scale characterization of silicon diffusion on carbon nanotubes

► Stable adsorption sites for a single Si atom adsorption on the outer surface of single-walled carbon nanotubes were studied in detail. ► Relative stability of equilibrium configurations above different C−C bonds cannot be judged only by the relative reactivity of the C−C bonds, due to the radial deformation of tube caused by adsorption of Si atom. This is contrary to the case of the adsorption of C and N. ► Energetically favorable diffusion paths were determined, which is crucial for the growth of silicon carbide nanotubes. No studies on this issue have been reported.