DFT exploration of adsorptive performances of borophene to small sulfur-containing gases.

Density functional theory (DFT) calculations were applied to study the ability of B to adsorb HS, SO, SO, CHSH, (CH)S, and CHS gases. Several exchange-correlation including B97D, PBE, B3LYP, M062X, and WB97XD were utilized to evaluate adsorption energies. The initial results showed that boundary boron atoms are the most appropriate interaction sites. The adsorption energies, electron density, electron localized function, and differential charge density plots confirmed the formation of chemical covalent bonds only between SO and B. The results of thermochemistry analysis revealed the exothermic nature of the adsorption of sulfur-containing gases on B; the highest values of ∆H were found for SO/B and SO/B systems. The electronic absorption spectra and DOS of B did not exhibit significant variations after gases adsorption, while the modeled CD spectra showed a remarkable change in the case of the SO/B system. Accordingly, B is not suggested for detecting the studied gases. The effect of imposing mono vacancy defect and external electric field to the adsorption of titled gases on the sorbent showed, while the former did not affect the adsorption energies significantly the later improved the adsorption of gas molecules on the B system. The results of the current study could provide deeper molecular insight on the removal of SO gases by B system.