MoS2 containing (Si, Se, P+Cl) structure doping and (Au and Ag) surface decorating as a sensor of Methanethiol biomarker: A first-principles study

Abstract

MoS${}_2$ monolayer is a highly promising material for gas and biosensors due to its exceptional physical and chemical properties. Recent research suggests that modified MoS${}_2$ monolayers demonstrate improved properties compared to unmodified ones. In this study, we employed density functional theory to investigate MoS${}_2$ doped and decorated with transition metallic atoms such as Ag and Au, as well as non-metallic atoms like Se, Si, P, and Cl, for the detection of the Methanethiol biomarker. In this regard, the adsorption energy, charge transfer, adsorption distance, I–V, TDOS, PDOS, and sensitivity are calculated for each structure. The results reveal that the adsorption energy and charge transfer of the Methanethiol biomarker on MoS${}_2$ modified with Ag, Au, and Si atoms are higher than that of unmodified MoS${}_2$. The most significant changes in I–V curves and chemical adsorption occur in these structures. The highest sensitivity is achieved when the MoS${}_2$ monolayer is decorated with Ag atoms, Au decorated, and doped with two Si atoms, respectively. Also, doping with Se, P, and Cl atoms results in the lowest adsorption energy, charge transfer, and sensitivity. This study provides valuable insights into the potential applications of both unmodified and modified MoS${}_2$ as Methanethiol biomarker sensor materials.