Theoretical study of the structural and electronic properties of novel stanene-based buckled nanotubes and their adsorption behaviors

•DFT calculations were carried out to investigate the structural and electronic properties of stanene based nanotubes.•The (4, 4) a-Sn-NT only has two indirect band gaps of 0.45 eV between V2 and C1 and V2 and C2 .•(5, 5) NT has both direct band gap between V1 and C2, and indirect band gap between V2 and C2.•(4, 0) and (7, 0) NTs are metallic, while others with a direct band gap at ᴦ point are semiconductors.•In (6, 6) a-SnNT, the orbitals corresponding to CBM, was localized on inner Sn atoms and smeared in spaces between outer Sn atoms.