Lateral MoS₂Heterostructure for Sensing Small Gas Molecules

Abstract

The potential of a two-dimensional (2D) molybdenum disulfide (MoS2) lateral heterostructure in sensing small gas molecules is being assessed on the basis of quantum mechanical calculations. This heterostructure combines two phases of MoS2, namely, a metallic ribbon embedded within the semiconducting MoS2 phase. In this work the influence on the electronic structure of this 2D material due to the adsorption of gas molecules is investigated. Specifically, the adsorption of NO, NO2, O2, CO, and CO2 on the MoS2 heterostructure is studied. Overall, gas-specific peaks in the electronic features of the 2D material could be clearly revealed, while differences were also found for a gas adsorption close to the interfaces of the material. The “poisonous” nitrogen oxide molecules showed a stronger adsorption on the material but could very well be distinguished over the “healthy” molecular oxygen gas. The complexity of the heterostructure provides more rich gas adsorption characteristics over the single-phase material and is thereby expected to show an enhanced sensitivity due to the increased statistics and the wider window of gate voltages that can be applied. This work provides a proof of principles on the high relevance of the 2D MoS2 heterostructure in view of response materials in gas detectors.

Computational Study of the Adsorption of NO2 on Monolayer MoS2

“…Zhao et al and Babar et al proposed the structure shown in Figure d in which the NO 2 forms a bridge between Mo sites. Schleicher and Fyta obtained a very similar structure except that the NO 2 appears to be displaced slightly away from the Mo atoms and toward the adjacent S atoms. Finally, Yue et al, Luo et al, Cho et al, and Zhang et al identified the structure in Figure e, with one O atom above a Mo site and the NO 2 projecting into a hollow, which appears to be the lowest in Δ E ads .…”

The first-principles study of the adsorption of NH3, NO, and NO2gas molecules on InSe-like phosphorus carbide

“…10 The discovery of new 2D materials, such as phosphorene, has shown that these materials may provide much stronger adsorption ability to ambient molecules and gases compared to MoS 2 or InSe. 9,[11][12][13] The promoted activity of phosphorene has been reported for the NO, NO 2 , NH 3 , and CO molecules. 14,15 In addition, the gas sensing ability of phosphorene has been improved by the doping of its surface by NH 3 and NO 2 gas molecules.…”

As-Doped h-BN Monolayer: A High Sensitivity and Short Recovery Time SF6 Decomposition Gas Sensor

“…Therefore, it is necessary to further develop gas sensors that can cover SO 2 F 2 and other major SF 6 decomposition gases. With the development of computer science, the DFT method based on quantum mechanics has been widely used in the field of gas sensing [21][22][23][24][25][26][27][28][29][30][31][32]. According to previous research, the material properties calculated by the DFT method have high consistency with the experimental results, which confirms the feasibility of this method in the field of gas sensing.…”