Interaction of hydrogen sulfide with the pristine and B&N-doped beryllium oxide nanotube: DFT study

Abstract

ABSTRACT In this study, hydrogen sulfide interaction with pristine, B-, N-, and B&N atom-doped beryllium oxide nanotube (BeONTs) is investigated by the density functional theory (DFT) method. At the first step, we considered different configuration models for the adsorption of H2S on the surface of nanotube and then we selected 12 stable models for this study. The structures of all selected models are optimized and the quantum properties, thermodynamic parameters, natural bond orbitals (NBO), reduced density gradient (RDG), molecular electrostatic potential (MEP), and atom in molecule (AIM) parameters are calculated at the cam–B3LYP level of theory with 6–31G (d) base set. The obtained Eads for the exterior surface of nanotube is exothermic and is in the range –3.15 to –28.34 Kcal mol–1, and that for the interior surface is endothermic and is in the range 19.17 to 27.17 kcal mol–1. The gap energy for pure, B-doped, N-doped, and B&N-doped BeONTs is 10.11, 10.03 (α spin), 10.13 (α spin), and 9.35 eV, respectively. The results of thermodynamic parameters, such as ΔG and ΔH values for the adsorption of H2S, on the surface of B-doped BeONTs are more negative than other models and favorable in thermodynamic approach. The NBO, MEP, NMR, and HOMO–LUMO results confirm that the electron charge transfer occurs from H2S molecule toward BeONTs, as a result the bonding type of H2S … BeONTs is weak ionic.