Density functional studies of oxygen-terminations versus hydrogen-terminations in carbon and silicon nanotubes

• Published in: Solid state sciences 2012-07, Vol.14 (7), p.874-879
• Main Authors: Mirzaei, Mahmoud, Yousefi, Mohammad, Meskinfam, Masoumeh
• Format: Article
• Language: English
• Subjects: Carbon; Carbon nanotube; Chemical bonds; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Density; Density functional theory; Dipole moment; Electron states; Energy gap; Exact sciences and technology; Hydrogen termination; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials science; Mathematical models; Methods of electronic structure calculations; Nanoscale materials and structures: fabrication and characterization; Nanotubes; Oxygen termination; Physics; Silicon; Silicon nanotube; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 1293-2558; 1873-3085
• DOI: 10.1016/j.solidstatesciences.2012.04.026

We performed density functional theory (DFT) calculations to investigate the properties of hydrogen-terminated and oxygen terminated models of representative structures of carbon and silicon nanotubes. Different models based on terminating atoms were constructed for each nanotube; model 1: two-end H-terminated, model 2: one-end O-terminated and the other end H-terminated, and model 3: two-end O-terminated. The results of obtained parameters including energy gaps, binding energies, dipole moments, bond lengths, and chemical shifts for the optimized models of the investigated nanotubes indicated that the atomic level properties of nanotubes changed more in the O-terminated models than the H-terminated model. Moreover, the O-terminations could change the magnitude of energy gaps and dipole moments. And finally, for investigating the properties of nanotubes, H-terminations models of nanotubes could be more preferred than other types of terminations. [Display omitted] ► H-terminated nanotubes are preferred than O-terminated nanotubes. ► The effects of terminating atoms are significant for the nanotubes. ► The atoms of silicon nanotubes detect more effects of terminating atoms than carbon atoms.