Adsorption and Gas-Sensing Performance of the Small-Molecule Gas on ZrSe<sub>2</sub> Monolayers: A First-Principles Study
Kui Liu, Long Lin, Kun Xie, Pei Shi, Dongxia Xu
Abstract
The adsorption of five small gas molecules (CO, CO 2, NO, NO 2, and NH 3 ) on transition metal (TM)-modified ZrSe 2 monolayers (Au-ZrSe 2 and Pt-ZrSe 2 ) are studied based on first principles. The adsorption structure, adsorption energy ( E ads ), electron transfer ( Q t ), and density of states (DOS) with intrinsic ZrSe 2, Au-ZrSe 2, and Pt-ZrSe 2 monolayers are discussed, and their sensing performance is evaluated. The results show that the electrical conductivity of ZrSe 2 is obviously increased after Au and Pt atom modification. The intrinsic ZrSe 2 adsorbs the five kinds of gas molecules weakly, while ZrSe 2 modified by the Au or Pt atom improves the adsorption of the gas molecules in different degrees. Au-ZrSe 2 has the best adsorption effect on NO 2 gas molecules, while Pt-ZrSe 2 shows strong sensitivity to CO gas molecules. Moreover, Au-ZrSe 2 and Pt-ZrSe 2 are of great significance for the adsorption sensing mechanism and also offer prospective materials for the advancement of gas-sensitive sensors.