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 play as a physisorption nature through van der Waals force, whereas NO2 found to be as chemisorption nature. We observed that at room temperature, NH3 and NO molecules exhibit a very short recovery time as 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 donating charges to the 2D P2SiS nanosheet. Moreover, it has also revealed a superior I-V response and sensitivity of NCG molecules towards the 2D P2SiS nanosheet. Thus, we suggest that 2D P2SiS nanosheet can be used as a highly sensitive and multi-time reusable gas sensor for NH3 and NO gas molecules, whereas disposable gas sensor for NO2 molecule.