Exploring on the possibility of GeS used as small-molecule gases sensing.

The adsorption of small-molecule gases (NO2, SO2, NO, H2, N2, O2, CO, CO2, H2O, H2S, and NH3) on GeS was studied using first-principles density functional theory (DFT). The study revealed that, among the small-molecule gases, NO2, SO2, and NO present the highest adsorption energies of 0.746 eV, 0.466 eV, and 0.412 eV, respectively. Moreover, the monolayer GeS transforms from a non-magnetic state to a magnetic state with a magnetic moment of 1 μ B after NO2 or NO adsorptions, resulting in significant changes in the electronic band structures. Especially, for the NO2 adsorption system, exhibited exceptional adsorption density and an I–V curve shift demonstrate that GeS has high selectivity for sensing NO2 gas. Therefore, our research results indicate that GeS is a promising candidate material for NO2 gas sensing. [ABSTRACT FROM AUTHOR]