Adsorption and Gas-Sensing Performance of the Small-Molecule Gas on ZrSe 2 Monolayers: A First-Principles Study

The adsorption of five small gas molecules (CO, CO , NO, NO , and NH ) on transition metal (TM)-modified ZrSe monolayers (Au-ZrSe and Pt-ZrSe ) are studied based on first principles. The adsorption structure, adsorption energy ( ), electron transfer ( ), and density of states (DOS) with intrinsic ZrSe , Au-ZrSe , and Pt-ZrSe monolayers are discussed, and their sensing performance is evaluated. The results show that the electrical conductivity of ZrSe is obviously increased after Au and Pt atom modification. The intrinsic ZrSe adsorbs the five kinds of gas molecules weakly, while ZrSe modified by the Au or Pt atom improves the adsorption of the gas molecules in different degrees. Au-ZrSe has the best adsorption effect on NO gas molecules, while Pt-ZrSe shows strong sensitivity to CO gas molecules. Moreover, Au-ZrSe and Pt-ZrSe are of great significance for the adsorption sensing mechanism and also offer prospective materials for the advancement of gas-sensitive sensors.