Gas adsorption on MoS2 monolayer from first-principles calculations

TL;DR

This study uses first-principles DFT calculations to analyze gas molecule adsorption on MoS2 monolayers, identifying strong binding for NO and NO2, and providing insights into their electronic interactions relevant for gas sensing applications.

Contribution

It offers a theoretical analysis of gas adsorption on MoS2, highlighting the selective binding of NO and NO2 with detailed electronic structure insights.

Findings

NO and NO2 bind strongly to MoS2 with large adsorption energies

Charge transfer and electronic structure changes explain gas sensing behavior

Results align with experimental observations

Abstract

First-principles calculations within density functional theory (DFT) have been carried out to investigate the adsorption of various gas molecules including CO, CO2, NH3, NO and NO2 on MoS2 monolayer in order to fully exploit the gas sensing capabilities of MoS2. By including van der Waals (vdW) interactions between gas molecules and MoS2, we find that only NO and NO2 can bind strongly to MoS2 sheet with large adsorption energies, which is in line with experimental observations. The charge transfer and the variation of electronic structures are discussed in view of the density of states and molecular orbitals of the gas molecules. Our results thus provide a theoretical basis for the potential applications of MoS2 monolayer in gas sensing and give an explanation for recent experimental findings.