First-principles study of Co-doped single-walled silicon nanotubes

We performed spin-polarized density functional calculations to study the stable configurations, energetics and electronic structures of Co-doped single-walled silicon nanotubes (CoSi(2)NTs) with the stoichiometry of CoSi(2). We found that the incorporation of Co atoms into the wall of SiNTs not only effectively stabilizes the tubes but also tunes their electronic properties. The formation energies of the CoSi(2)NTs are much lower than those of pristine SiNTs, indicating the plausibility of these tubes. The electronic structures of the CoSi(2)NTs display the characters of metals. This provides a promising synthetic route to stable SiNTs which may find potential applications in building nanoscale devices.