Investigation of NH3 adsorption on noble metal modified MoSe2

Abstract

Gas pollutants represent hazard for the quality of the ambient environment, thus, the development of sensitive and selective gas sensors is essential to monitor and maintain its decent quality. The adsorption of NH3 gas on pristine and noble metal doped molybdenum diselenide (MoSe2) structures is investigated by density functional theory (DFT) computations. The metals used for doping are Pt, Au, Ag, and their combination. The work discusses the effect of doping on the adsorption energy, charge transferred among MoSe2 structures and NH3 gas, adsorption distance, density of states (DOS), and band structure. The DOS as well as band structure of the modified MoSe2 show substantial modifications in the electronic properties as compared with the pristine structure. New energy bands are developed close to the Fermi level due to doping of MoSe2 structure. The NH3 gas adsorption on the doped structures is significantly enhanced, compared with the pure MoSe2 structure, where the adsorption energy and distance for NH3 gas are improved, thus, the sensitivity is enhanced sensitivity compared with the pure MoSe2 structure. This investigation demonstrates that noble metal doping of MoSe2 can be an effective method to develop sensitive detectors for NH3 gas.