Small-radius clean and metal-doped boron carbide nanotubes: a density functional study

We present the results of ab initio density functional theory calculations of the atomic and electronic structure of small radius boron carbide nanotubes, and the effects of doping these tubes with Li and Cu atoms. We have found that undoped narrow tubes are more energetically favorable than the corresponding boron carbide strips. The effects of doping on the atomic and electronic structure of these tubes have been found to be dependent on the size and symmetry of the tubes, and the type of dopant atoms.