Multilayer structures of self-assembled gold nanoparticles as a unique SERS and SEIRA substrate.

Metallic multilayer structures consisting of self-assembled nanoparticles are prepared by successive immersion of a functionalized glass substrate in a gold colloidal suspension, and are characterized by UV/Vis spectroscopy and atomic force microscopy. The ability of the thin film to concomitantly enhance the Raman and IR signals of an adsorbed molecule is evaluated and a detailed analysis of the recorded spectra is provided, which emphasizes the capability of these complementary methods to provide information about the adsorbed species. This unique surface-enhanced Raman spectroscopy (SERS) and surface-enhanced infrared absorption (SEIRA) substrate could be further used for applications in the elucidation of the structure of a great variety of adsorbed samples.