Metal coating on suspended carbon nanotubes and its implication to metal–tube interaction

Coating of various metals on suspended single-walled carbon nanotubes (SWNT) is carried out by electron-beam evaporation. Transmission electron microscopy studies reveal that Ti, Ni and Pd coatings on the suspended tubes are continuous and quasi-continuous, resulting in nanotube-supported metal nanowire structures. In strong contrast, Au, Al, and Fe coatings on the suspended SWNTs only form isolated discrete particles on the nanotubes. These results shed light into the nature of metal–tube interaction, an important topic to many fundamental and practical aspects of nanotubes.