SO2 gas adsorption on the transition metal (Pd, Ag, Au and Pt) -doped monolayer MoSe2: A first-principles study

[Display omitted] •The analysis of the adsorption of SO2 gas molecules reveals that the Pd, Ag, Au and Pt doped monolayer MoSe2 can significantly enhance the adsorption properties, chemical activity and the sensitivity of the MoSe2, comparison to that of pristine monolayer MoSe2.•The adsorption of SO2 gas molecule is very strong on the metal (Pd, Ag, Au and Pt)-doped MoSe2.•The total electrostatic potential plots the chemisorbed of gas molecules on the surface of metal (Pd, Ag, Au and Pt)-doped monolayer MoSe2. We predict SO2-sensing performance of Pd, Ag, and Au,Pt -doped MoSe2 monolayer by the density functional theory (DFT). The results demonstrate that the adsorption of SO2 gas molecule on the MoSe2 is energetically favorable, which gives rise to the most stable configurations. Besides, the SO2 gas molecule are physisorbed on the pristine MoSe2 monolayer surface due to the weak interface combination, with metal doping, the adsorption energy and chemical adsorption are all enhanced. Most notably, the meatal doped MoSe2 monolayer might be a good candidate for low-cost, highly active, and stable catalysts and gas sensors, providing an avenue to facilitate the design of high active MoSe2-based two-dimensional gas sensors.