DFT investigation of H2S and SO2 adsorption on Zn modified MoSe2

Abstract

Development of decidedly sensitive and selective gas sensors is desirable to maintain control of environment quality against hazardous pollutant. The adsorption of H 2 S and SO 2 molecules on pristine and Zn doped MoSe 2 structures is examined by first principles computations - density functional theory (DFT). The work involves analysis of adsorption energy and distance, charge transferred between a structure and a gas molecule, band structure, and density of states (DOS). The band structure of MoSe 2 reveals substantial variations of its electronic properties upon doping with Zn. Furthermore, new bands have been developed near the Fermi level within the DOS due to Zn doping of MoSe 2 structure. The adsorption of both H 2 S and SO 2 gases on Zn–MoSe 2 structure is greatly enhanced, as compared with the pristine structure. The Zn-modified MoSe 2 structure exhibits larger adsorption energy for H 2 S gas, hence, better sensitivity is comparison with SO 2 gas. This work illustrates that Zn doping of MoSe 2 structure may be considered for sensitive detection of H 2 S gas. • Zn doped MoSe 2 was explored for sensors applications of H 2 S and SO 2 gases using DFT calculation. • The gas adsorption capacity was investigated using: adsorption energy and distance, charge transferred, and DOS. • Excellent improvement was observed for H 2 S and SO 2 adsorption after doping. • Adsorption energy for H 2 S gas of Zn-MoSe 2 structure was 5.5 times more than that of the pristine structure. • Adsorption energy for SO 2 gas of Zn-MoSe 2 structure was 3 times more than that of the pristine structure.