Defect-controlled transport properties of metallic atoms along carbon nanotube surfaces

The diffusion mechanism of indium atoms along multiwalled carbon nanotubes is studied by means of photoemission spectromicroscopy and density functional theory calculations. The unusually high activation temperature for diffusion ($\ensuremath{\approx}700\text{ }\text{ }\mathrm{K}$), the complex C $1s$ and In $3{d}_{5/2}$ spectra, and the calculated adsorption energies and diffusion barriers suggest that the indium transport is controlled by the concentration of defects in the C network and proceeds via hopping of indium adatoms between C vacancies.