摘要

The stability of M-Au(111) surfaces modified by M (M = In, Ir) was investigated using density functional theory. The most favorable model was selected to explore the chemical reactivity and adsorption of crotonaldehyde. The stability of the M-Au(111) surfaces was calculated using geometric configuration, and formation and cohesive energies. The calculations showed that the stability of the In-Au(111) surface increased as the atomic spacing of In was increased. Conversely, the Ir-Au(111) showed the opposite trend. The adsorption at the Top(M) site was most stable when the crotonaldehyde on the M-Au(111) surfaces interacting via the C=0. Additionally, the adsorption energies were at their maximum. A combination of structural changes, density of state, deformation density and Mulliken charge analysis showed that the deformation of crotonaldehyde was larger than other adsorption modes, with an obvious charge transfer. Additionally, p and d orbital hybridization between -7.04 eV to Fermi level was found to have an important contribution to the adsorption process. Compared with the Au(111) surface, the stability and adsorption capacity of the M-Au(111) surfaces were significantly improved following modification by M atoms. Importantly, the Ir-Au(111) surface was found to have higher stability and activity, and stronger adsorption of crotonaldehyde than the In-Au(111) surface.