First-principles study of the adsorption behavior and sensing properties of C2H4 and C2H6 molecules on (CuO/TiO2)n (n=1–3) cluster modified MoTe2 monolayer

Abstract

Based on density functional theory, this study performed a theoretical calculation on the modification of (CuO/TiO2)n (n=1–3), abbreviated as (TMO)n cluster on the MoTe2 monolayer. The adsorption behavior of C2H4 and C2H6 gas on (TMO)n cluster modified MoTe2 monolayer was analyzed. The research results show that the modification of (TMO)n cluster enhances the conductivity of the MoTe2 monolayer. The sensitivity of (CuO)n-MoTe2 monolayer to C2H4 and C2H6 gas decreases with the increase of (TMO)n clusters, while the sensitivity of (TiO2)n-MoTe2 monolayer to C2H6 gas is the opposite. In addition, (TMO)n clusters greatly enhance the orbital hybridization and deformation density between gas molecules and modified structures. In the adsorption process, the strong hybridization between the (TMO)n-MoTe2 work function and the C2H4 gas molecular orbital belongs to the n-type doping modification process, and the C2H6 gas adsorption belongs to the p-type. As a result, (TMO)n (n=1–3) modified MoTe2 monolayer may be potential candidates for the selective detection of C2H4 and C2H6 due to the different changing tendencies of conductivity upon gas adsorption.