Electronic structure of boron nitride nanotubes intercalated with transition metals

Abstract

The electronic structure of semiconductor (5,5) boron nitride nanotubes intercalated with 3d metals has been studied by quantum-chemical methods. The linear augmented-cylindrical-wave method has been used for calculating the total and partial densities of electronic states as a function of metal concentration and nature and the structure of the carbon shell. Metallized nanowires based on (5,5) BN nanotubes with one, two, three, and four metal atoms in the cross section have been calculated. The introduction of metals is accompanied by the insulator-to-metal transition of the nanotubes. For forty inorganic materials, we have determined the total densities of states of the valence band and the conduction band and the density of states at the Fermi level, which determines the concentration of free electrons that can be involved in ballistic charge transport in the nanotube. The introduction of metals not only has an effect on the conductive state of the boron nitride nanotube but also change the whole pattern of the valence band of the nanotube, in particular, increases the valence band width by 2–10 eV owing to the low-energy shift of the boron and nitrogen states.