SURFACE-ENHANCED RAMAN SCATTERING STUDY ON NON-ACTIVITY OF Ag-Cl CLUSTERS

The non-active mechanism of Ag-Cl clusters in surface-enhanced Raman scattering (SERS) was discussed on the basis of the study of the interaction and adsorption competition of chlorions with a series of compounds: benzoic acid, p-hydroxybenzoic acid, and m-hydroxybenzoic acid on silver surface. As a result of the addition of chlorions, the SERS signals of these molecules were sharply and rapidly reduced and quenched in intensity. The change of Raman bands at 1644 cm^-1 for benzoic acid, and at 1636 cm^-1 for p-hydroxybenzoic acid and m-hydroxybenzoic acid, before and after the addition of chlorions, indicated the desorption process of these adsorbed molecules, and the adsorption behavior of the molecules remaining adsorbed on the silver surface.