Selectivity and Sensitivity Evaluation of Embedded BN-Nanostructure as a Gas Detector for Air Pollution Scavenging: a Theoretical Study

Abstract

This article aims to investigate the structural, electromagnetic, and thermodynamic properties of toxic gases molecules including nitric oxide (NO), nitrogen oxide (NO2), and nitrous oxide (N2O) during adsorption on the surface of boron nitride (B5N10) nanocage which has been decorated with aluminum (Al), carbon (C) and silicon(Si) atoms. The results denote that (NO,NO2,N2O) <-> (Al, C, Si)-B4N10 are stable complexes with the most stable adsorption site being the center of the cage ring. The partial density of states can estimate a certain charge assembly between gas molecules and (Al, C, Si)-B4N10 which indicates the competition among dominant complexes of metallic (Al), nonmetallic (C), metalloid/semiconductor (Si). Based on nuclear quadrupole resonance analysis, carbon-doped on B4N10 has shown the lowest fluctuation in electric potential and the highest negative atomic charge including 0.1190, 0.1844, and 0.1312 coulomb in NO <-> C-B4N10, NO2 in NO <-> C-B4N10, and N2O in NO <-> C-B4N10, respectively, can be an appropriate option with the highest tendency for electron accepting in the adsorption process. Furthermore, the reported results of nuclear magnetic resonance spectroscopy have exhibited that the efficiency of electron accepting for doping atoms on the (Al, C, Si)-B4N10 through gas molecules adsorption can be ordered as: Si > Al >> C that indicates the power of covalent bond between aluminum, carbon, silicon and these NO, NO2, N2O towards toxic gas removal from air. In fact, the adsorption of gas molecules can introduce spin polarization on the (Al, C, Si)-B4N10 which indicates that these surfaces might be applied as magnetic scavenging surface as a gas detector. Regarding infrared spectroscopy, doped nanocages of C-B4N10 and Si-B4N10 for NO, Al-B4N10 and Si-B4N10 for NO2, Al-B4N10 and C-B4N10 for N2O, respectively, have the most fluctuations and the highest adsorption tendency for gas molecules which can address specific questions on the individual effect of charge carriers (gas molecule-nanocage), as well as doping atoms on the overall structure. Based on the results of Delta G(ads)(o )amounts in this research, the maximum efficiency of Al, C, Si atoms doping of B5N10 for gas molecules adsorption depends on the covalent bond between NO, NO2, N2O molecules and (Al, C, Si)-B4N10 as a potent sensor for air pollution removal.