A theoretical study on adsorption and sensing of SO2, CS2, CO2, CH2O, H2O, C2H2, and CF3H air pollutant gases by B3S monolayer

Abstract

In the present work, with the aid of the density functional theory (DFT) method, we have investigated the possibility of applying the B₃S monolayer (B3SML) for sensing and adsorption of some air pollutants containing SO₂, CS₂, CO₂, CH₂O, H₂O, C₂H₂, and CF₃H from the gaseous environment. The results showed that after the adsorption of SO₂, H₂O, and C₂H₂ by B3SML, big changes took place which led to a decrease of the λ_max of each complex down to 1598.5 nm, 1418.0 nm, and 1580.0 nm, respectively. Therefore, the frequencies of the mentioned adsorption complexes rise and strong blueshifts occur. Moreover, the outcomes of the band gap estimations reveal that the B3SML could selectively detect the existence of C₂H₂ with a clearer and stronger electronic signal compared to all other gases. In addition, this nanosheet is able to sense CS₂, CH₂O, SO₂, and H₂O with good signals. Hence, it could not recognize the difference between CH₂O and SO₂ gases. Also, the results of the thermodynamic calculations indicate that B3SML would selectively adsorb and destruct SO₂, C₂H₂, and H₂O gases. Moreover, this sorbent could adsorb CH₂O and CS₂ species, but it would approximately not adsorb CO₂ and CF₃H.