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 NH 3 gas on pristine and noble metal doped molybdenum diselenide (MoSe 2 ) 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 MoSe 2 structures and NH 3 gas, adsorption distance, density of states (DOS), and band structure. The DOS as well as band structure of the modified MoSe 2 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 MoSe 2 structure. The NH 3 gas adsorption on the doped structures is significantly enhanced, compared with the pure MoSe 2 structure, where the adsorption energy and distance for NH 3 gas are improved, thus, the sensitivity is enhanced sensitivity compared with the pure MoSe 2 structure. This investigation demonstrates that noble metal doping of MoSe 2 can be an effective method to develop sensitive detectors for NH 3 gas. • MoSe 2 was investigated for its adsorption of ammonia gas using DFT calculation. • The effect of noble metal doping of MoSe 2 on its adsorption parameters for NH 3 was examined. • The adsorption capacity was examined by investigation of adsorption distance and energy, charge transfer, and DOS. • Excellent enhancement was observed for NH 3 adsorption upon doping with Pt, Au, and Pt–Au–Ag. • Adsorption energy towards NH 3 gas for Pt–MoSe 2 was 3.5 times greater than that of the pristine structure.