Defect-induced junctions between single- or double-wall carbon nanotubes and metal crystals.

Interfaces between the ends of single- or double-wall carbon nanotubes and metal crystals (Fe, Co, Pd, and Pt) are established by electron irradiation with nanometre precision at metal-nanotube contact areas. Calculations of the bonding energies at the metal-nanotube interfaces confirm that the formation of these covalent junctions is energetically favourable in the presence of a certain concentration of structural defects in the nanotubes. The process may be endothermic or exothermic in comparison with the unconnected configuration, but in either case atomic defects in carbon nanotubes are a necessary condition for joining them with metals.