Theoretical study of M6X2 and M6XX′ structure (M = Au, Ag; X, X′ = S, Se): Electronic and optical properties, ability of photocatalytic water splitting, and tunable properties under biaxial strain

MoS2, a transition metal dichalcogenide (TMDC), has attracted significant amount of attention due to its direct bandgap, tunability and optical properties. Recently, a novel structure consisting of MoS2 and noble metal nanoclusters has been reported. Inspired by this, first principle calculations are implemented to predict the structures of M6X2 and M6XX' (M = Au, Ag; X, X' = S, Se). The calculated bandgap, band edge position, and optical absorption of these structures prove that the silver compounds (Ag6X2 and Ag6XX') have great potential for catalytic water splitting. In addition, biaxial strain (tensile strain and compressive strain) is applied to adjust the properties of these materials. The bandgap presents a quasi-linear trend with the increase of the applied strain. Moreover, the transition between the direct and indirect bandgap is found. The outstanding electronic and optical properties of these materials provide strong evidence for their application in microelectronic devices, photoelectric devices, and photocatalytic materials.

Automated summary

MoS2, a transition metal dichalcogenide, has direct bandgap, tunability, and optical properties. By combining with noble metal nanoclusters, it can be used for catalytic water splitting. The properties of these materials can be adjusted by applying biaxial strain, which leads to a quasi-linear relationship between the bandgap and strain and a transition between direct and indirect bandgap. These materials exhibit excellent electronic and optical properties, making them important for applications in microelectronic and photoelectric devices, as well as photocatalytic materials.