SF6 Decomposition Gas Sensor Based on GeP Monolayer: A First-Principle Study

In this paper, we adopted the first-principles calculations to investigate the sensing properties of the GeP monolayer to four SF6 decomposition gas molecules (H2S, SO2, SO2F2 and SOF2). By discussing the calculated adsorption energy, charge transfer, work function variation combined with charge density difference and electron localization function analysis, we find that GeP monolayer exhibits favorable adsorption strength to SO2 molecule with the most intense charge interaction. And SO2 adsorption can remarkably change the density of states (DOS) of GeP monolayer. Furthermore, we also study the adsorption performance of SO2 molecule on GeP monolayer under applied biaxial strain and external electric field. And the results demonstrate that applying negative electric field can significantly enhance the sensitivity of GeP monolayer to SO2. Therefore, GeP monolayer is a potential candidate for highly sensitive and selective tunable SF6 decomposition gas sensor for on-line diagnostics of power equipment.