Sensing of NO, NO2, and SO2 on two dimensional WS2 doped with Al, P, and Fe: An ab initio study

Abstract

Owing to their harmful and polluting the environment, nitrogen oxides and sulfur dioxide are expected to monitor when they are used. However, the widespread use of gas sensing methods presents obstacles in terms of portability or stability. Hence, a better detect way needs to be found urgently. The success of graphene-based gas sensors has stimulated interest in two-dimensional (2D) materials in the gas sensing area. Transition metal dichalcogenides (TMDs), such as MoS2 or WS2, are considered to have the high-performance potential for gas sensors. Unfortunately, when used as a gas sensor, the sensing response of the pristine TMDs is greatly affected by a number of gas molecules that are too weak to be detected. Herein, to evaluate the sensing capability of Al, P, and Fe-doped WS2 to NO, NO2, and SO2, the molecular model of the adsorption systems was constructed, and density functional theory (DFT) was used to calculate the adsorption behavior of these gases. The binding force of all the doped-WS2 to the harmful gas molecules is much stronger than that of the pristine WS2. According to the results of adsorption energy, band structure, and state density, Al-doped WS2 has the potential to be used as NO and SO2 gas sensor, while P-doped WS2 is selective to NO. This work opens up a new reference for choosing appropriate doping types on 2D materials for noxious gas sensing.

Superior Cryotronics Performance of the In/p-WS2 Schottky Interface

“…It follows the generalized formula of MX 2 (M is the transition-metal atom and X is the chalcogen atom) in which W lies in between two S atoms and they are connected by a covalent bond and form an S–W–S single layer. − WS 2 is also layered material in which two adjacent layers are bonded by weak van der Waals bonds that can be exfoliated by various methods. By this virtue, one can reduce the thickness of WS 2 material from multilayer to single layer where it can undergo the transition from indirect bandgap material to direct bandgap material. − Due to its semiconducting nature and moderate physical properties, WS 2 is utilized for various types of advanced solid-state device applications such as photodetector, diode, field-effect transistor (FET), and gas sensors. − …”