The adsorption of sulfur dioxide and ozone molecules on boron nitride nanotubes: A DFT study

Density functional theory calculations were carried out to investigate the adsorption behaviors and electronic structures of SO2 and O3 molecules on the pristine boron nitride nanotubes. The structural and electronic properties of the studied systems were investigated in view of the adsorption energies, band structures and molecular orbitals. Various adsorption positions of gas molecules on the boron nitride nanotubes were examined in detail. The band structure calculations indicate that the pristine BN nanotube works as a wide band gap semiconductor, and can be applied as an efficient candidate for SO2 and O3 sensing purposes. NBO analysis reveals that SO2 acts as a charge donor, whereas O3 molecule behaves as a charge acceptor from the BN nanotube. Molecular orbital calculations indicate that the LUMOs were dominant on the nanotube surface, whereas the electronic densities in the HOMOs were mainly distributed over the adsorbed SO2 and O3 molecules. Moreover, the charge density difference calculations indicate charge accumulation on the adsorbed gas molecule.