Sensing applications of GeBi nanosheet for environmentally toxic/non-toxic gases: Insights from density functional theory calculations

Abstract

To the league of fast-growing two-dimensional materials, the GeBi compound is a recent addition to this series. The exciting prospects of 2D GeBi compound for gas sensing applications, we have been calculated by incorporating the density functional theory (DFT), and non-equilibrium Green's function (NEGF) based techniques. Herein, we have calculated the adsorption mechanics for toxic/non-toxic gas molecules (NO₂, SO₂, NO, O₂, CO₂, and H₂S) on a GeBi nanosheet by first-principle calculations. Our findings strongly suggest the superior sensing efficiency of GeBi nanosheet which is close or even surpasses that of other 2D materials such as graphene, silicene, germanene, and, bismuthine, etc. In this work, we have extensively explored the structural, adsorption sites, binding energy, charge transfer, and current–voltage characteristics for all gas molecules on GeBi nanosheet. Our findings show that the GeBi nanosheet is very responsive towards NO₂, SO₂, NO, and O₂ molecules, although, low sensitive towards CO₂ and H₂S gas molecules. The results also indicate that NO₂ and O₂ molecules have a chemisorption process, whereas SO₂, NO, CO₂, and H₂S molecules have found to be of physisorption nature on the nanosheet. Our outcomes show that the GeBi nanosheet might be exceedingly suitable for a highly sensitive sensor for toxic/non-toxic molecular gases.