关键词: 密度泛函理论, 纳米管, 稳定性, 电子性质, 磁性质

Abstract: Electronic and magnetic properties of ZnS nanotubes (NTs) were investigated systematically using first-principles approach. A double-wall NT (DWNT) with hexagonal cross section (HCS) shows higher stability, while zigzag and armchair NTs with round cross section (RCS) show lower stability than single-wall NT (SWNT) with HCS. Electronic band structures show that they are direct band gap semiconductors. With hydrogen adsorption, SWNT with HCS transform into indirect band gap semiconductor. Magnetic properties of ZnS NTs doped with transition-metal(TM) atoms (Cr, Mn, Fe, Co, and Ni) are calculated. Formation energies of doped NTs are smaller than those of the pristine ones, indicating that doing process is an exothermic reaction. All NTs have atom-like magnetic moments mainly due to 3d component of the TM atoms. Monodoped NTs have potential utility in materials with tunable magnetic properties.

Key words: density functional theory, nanotube, stability, electronic property, magnetic property