Gas adsorption on MoS2 monolayer from first-principles calculations

摘要

First-principles calculations within density functional theory (DFT) havebeen carried out to investigate the adsorption of various gas moleculesincluding CO, CO2, NH3, NO and NO2 on MoS2 monolayer in order to fully exploitthe gas sensing capabilities of MoS2. By including van der Waals (vdW)interactions between gas molecules and MoS2, we find that only NO and NO2 canbind strongly to MoS2 sheet with large adsorption energies, which is in linewith experimental observations. The charge transfer and the variation ofelectronic structures are discussed in view of the density of states andmolecular orbitals of the gas molecules. Our results thus provide a theoreticalbasis for the potential applications of MoS2 monolayer in gas sensing and givean explanation for recent experimental findings.