2D-GeP3 as an exemplary prospect for NO sensing: unveiling highly sensitive and selective at room temperature

Novel two-dimensional (2D) materials have garnered significant attention for constructing ultra-sensitive gas sensors. This study explores the potential of a novel 2D-GeP 3 monolayer for sensing CO, CO 2 , NO, NO 2 , O 2 , and N 2 gases using first-principle calculations. The results reveal that the GeP 3 monolayer exhibits low sensitivity to CO 2 and N 2 gases due to low adsorption energies and minimal charge transfer. Conversely, it demonstrates appropriate adsorption properties for NO and CO, as well as strong chemisorption for NO 2 and O 2 molecules. Through an analysis of adsorption behavior, electronic and optical, and sensing characteristics, the GeP 3 monolayer shows high sensing capability for NO, NO 2 , and O 2 gases. Notably, it demonstrates appropriate selectivity and sensitivity for NO gas due to adsorption energy of −0.742 eV, charge transfer of −0.376 e, and significant changes in electronic properties upon interaction. Furthermore, the GeP 3 monolayer exhibits a short recovery time of 0.29 s at room temperature. Based on these findings, the GeP 3 monolayer holds promise as a reversible NO gas sensor and as an irreversible sensor for NO 2 and O 2 gas. These results serve as a valuable guide in subsequent experimental applications for using the GeP 3 monolayer in gas sensing devices.