The interaction of two-dimensional P2SiS nanosheet with environmental toxic NCG molecules for sensor application: A DFT study

Abstract

Gas sensors are vital ingredient substances for the detection of gas molecules on two-dimensional material due to their high surface-to-volume ratios. In this context, we have performed the environmentally toxic gas molecules sensing properties for NCG (NH3, NO2, and NO) molecules adsorbed on the 2D P2SiS nanosheet using density functional theory and NEGF approach. The significant effects are shown through the variation in adsorption strength, electronic properties, charge transfer, conductivity, work function, and recovery time. It is found that NH3 and NO molecules show physisorption through van der Waals forces, whereas NO2 prefers chemisorption on the P2SiS surface. We observed that at room temperature, NH3 and NO molecules exhibit a very short recovery time of 2.49 μs and 3.6 μs, respectively, while the same is noted to be quite large for the NO2 gas molecule. The amount of charge transfer found to be -0.03e, 0.74e, and 0.15e for NH3, NO2, and NO, respectively. The frequency calculation has also confirmed that structures belong to true local minima. NH3 molecule performs as the charge accepter, whereas NO and NO2 are noticed to donate charge to the 2D P2SiS nanosheet. Moreover, a superior I–V response and sensitivity of NCG molecules towards the 2D P2SiS nanosheet is also revealed in the present study. Thus, we suggest that 2D P2SiS nanosheet may be used as a highly sensitive and multi-time reusable gas sensor material for NH3 and NO gas molecules, whereas disposable gas sensor material for NO2 molecule.