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 H₂S and SO₂ molecules on pristine and Zn doped MoSe₂ 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 MoSe₂ 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 MoSe₂ structure. The adsorption of both H₂S and SO₂ gases on Zn–MoSe₂ structure is greatly enhanced, as compared with the pristine structure. The Zn-modified MoSe₂ structure exhibits larger adsorption energy for H₂S gas, hence, better sensitivity is comparison with SO₂ gas. This work illustrates that Zn doping of MoSe₂ structure may be considered for sensitive detection of H₂S gas.