Bismuth nanotubes: potential semiconducting nanomaterials

We have employed the first-principles molecular dynamics method to study the stabilities and electronic properties of bismuth nanotubes. There are some stable bismuth nanotubes. The strain energies of Bi(n, n) nanotubes follow the classical 1/D-2 strain law. For small Bi(n, 0) nanotubes, the strain energies show a non-linear dependence on 1/D-2. Bismuth nanotubes are predicted to be semiconducting in both (n, n) and (n, 0) forms. For small-diameter bismuth nanotubes, the band structure varies strongly because of hybridizations. As the diameters are larger than 18 A, the band C gaps of both Bi(n, n) and Bi(n 0) nanotubes approach 0.63 eV, corresponding to the band gap of a bismuth sheet at the F point. Thus 7 bismuth nanotubes are seen as potential semiconductor nanomaterials for future nano-electronics applications.