Theoretical Study of Monolayer PtSe2 as Outstanding Gas Sensor to Detect SF6 Decompositions

We adopted density functional theory combined with non-equilibrium Green's function to investigate monolayer PtSe2's gas sensing properties and adsorption of five types of SF6decompositions (SO2, SOF2, SO2F2, H2S, and HF), and explore the response of a simulated monolayer PtSe2-based device to these gases. We discussed the adsorption configurations, adsorption energy, electron transfer, electron localization function, density of states (DOS) including the chemical interactions, and the current-voltage property. These observations were relevant in studying the device response to different gas molecules. Changes in the molecule orbitals in DOS could approximately evaluate the chemical interactions among the gas molecules to a certain extent. Changing the bias voltage could adjust the response of the device to different gas molecules. Ultra-thin PtSe2can be a promising gas sensing material in detecting SF6decompositions.