Insight into the effect of alloying on the adsorption of benzene on Ag(100) surface: DFT calculations

Abstract

Heterogeneous catalysis, molecular sensors, and photovoltaics all rely on the interfaces between organic molecules and metal surfaces. Here, we study the adsorption of benzene on Ag(100) surface doped by Aun, Pdn, Ptn(n= 1–4), Au2Pd2, Au2Pt2 and Pd2Pt2 using density-functional theory (DFT), with the inclusion of van der Waals interactions, and compare with available computational and experimental result. The calculated quantities reveal that the interaction strength of Benzene with the surface gradually increases when it is doped by Pd or Pt atoms, showing a change in the nature of the interaction, from physisorption to chemisorption. We found that with surface allowing, one can tune the interaction strength. The charge transfer was found to occur from the molecule to the clean and doped surfaces with Au atoms and from the doped surface with Pd to the molecule. The redistribution of charge density indicates modifications in the features of the interface between the doped Ag(100) surfaces and benzene. In addition, alloying the Ag(100) surface with reactive TM changes substantially its electronic properties, which impacts its interactions with benzene. Finally, mixing two dopants or more can tune the electronic structure in designing more effective interfaces for various applications.