High Selective SO₂ Gas Sensor Based on Monolayer <inline-formula> <tex-math notation="LaTeX">$\beta$ </tex-math> </inline-formula>-AsSb to Detect SF₆ Decompositions

Abstract

The density functional theory with nonequilibrium Green's function was adopted to explore the adsorption of SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> decompositions (SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , SOF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> F <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> S, and HF) on monolayer β-AsSb as well as gas sensing response and selectivity using a simulated device. The adsorption on two side of monolayer β-AsSb was compared. Among these five kinds of gas molecule, for both the As and Sb adsorption sites, SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> exhibited the largest adsorption energy and electron transfer. The band gap of monolayer β-AsSb experienced a significant decrease only when SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> was adsorbed on the surface. All the five molecules can have chemical interactions with different degree according to density of states. The current-voltage property indicated that the monolayer β-AsSb-based sensing device had response to all these five gases, especially at the voltage range from about 1.6 to 1.8 V. But the response to SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> was obvious larger than other four gases for both As and Sb adsorption sites. The results suggest that monolayer β-AsSb has high response and selectivity to SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> which may stimulate future application for outstanding performance SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> gas sensor in SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> -based gas insulated equipment.