SERS effect from Pd surfaces coated with thin films of Ag colloidal nanoparticles

Surface-enhanced Raman scattering (SERS) effect provides huge intensification of the Raman signal of molecules adhering to nanostructured surfaces of high reflectivity metals as silver, gold and copper. Here, we present a method to provide SERS activation of palladium substrates by depositing thin layers of colloidal silver onto Pd surfaces pretreated with 1,10-phenanthroline. Density functional theory calculations have been carried out in order to simulate the structural and spectroscopic properties of the surface complex formed with the active sites of the Pd substrate and to get information about the type and strength of interaction between ligand molecules and palladium.