Sensing Properties of Au-Doped Stable Black Arsenic Phosphorus Monolayer for Small Gas Molecules

This study first used phonon dispersion curves to validate the structural stability of the pristine α-phase black arsenic phosphorus (AsP) monolayer, and then combined molecular dynamics simulations to assess its structural stability under 300°C conditions, confirming its good stability. The stability of the Au-doped AsP monolayer(Au-AsP) was also assessed through simulations following doping. Once the material's stability was confirmed, the research explored modifications in the material’s geometric structure, adsorption energies, charge transfer, orbital interactions in the electronic density of states (DOS) profile, and electronic band structure characteristics, after gas adsorption. The findings revealed that CO, NO₂, and NO molecules undergo chemical adsorption on the Au-AsP monolayer surface. During gas adsorption, notable characteristics such as rapid response and recovery times, significant charge transfer processes, as well as considerable alterations in conductivity and the work function of the material were observed. This study, for the first time, outlines a detailed gas-sensing mechanism for black arsenic phosphorus when exposed to small gas molecules, emphasizing its potential for sensing applications

Liujie Yang, Xiaolei Li, Tengfei Wang, Tiantian Xu, Jiahao Yang