Detecting Decompositions of Sulfur Hexafluoride Using MoS2 Monolayer as Gas Sensor

• Published in: IEEE sensors journal Vol. 19; no. 1; pp. 39 - 46
• Main Authors: Chen, Dachang, Tang, Ju, Zhang, Xiaoxing, Li, Yi, Liu, Huijun
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adsorption; Charge density; Charge transfer; Decomposition; Density functional theory; Electric potential; Electron transfer; Energy transmission; Gas detectors; Gas sensors; Gases; Hafnium; Hydrogen sulfide; Molybdenum; Molybdenum disulfide; Monolayers; MoS₂ monolayer; Negative conductance; non-equilibrium Green’s function; SF₆ decompositions; Spectrum analysis; Sulfur; Sulfur hexafluoride; transmission spectrum
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2018.2876637

The adsorption and gas sensing properties of monolayer MoS 2 to five kinds of sulfur hexafluoride decompositions (SO 2 , SOF 2 , SO 2 F 2 , H 2 S, HF) were explored using the density functional theory combined with the nonequilibrium Green's function. The adsorption energy, electron transfer, charge density difference configurations, current-voltage (I-V) character using a two-electrode based device and transmission coefficient have been discussed. The results show that the adsorption of SO 2 brings the largest adsorption energy as well as electron transfer. According to the simulated device, the unique negative conductance phenomenon was found for SO 2 . The MoS 2 monolayer-based sensor has the highest response to SO 2 when the bias voltage is 1.2 V, reaching 7.74 and has the largest response to H 2 S when 1.8 V. The transmission spectrum analysis shows that after introducing different gas molecules, the transmission coefficient has different changes in different energy ranges. This paper can provide a theoretical basis for designing MoS 2 monolayer-based gas sensing device to detect the decompositions of sulfur hexafluoride or other specific gases.