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A simple new preparation method for silver surface-enhanced Raman scattering (SERS) substrate (Ag/Cu film) was developed by reduction of aqueous Ag+ on copper foil, which is used for making print circuit board. The properties of the substrate were evaluated. The approximate limit of detection (LOD) was measured using 2,2′-bipyridine (bpy) and 1,1′-diethyl-trimethincyanine dye (TMC) as probing compounds. The LOD of bpy and TMC are 1 nanomole and 0.13 nanomole, respectively. The film-to-film reproducibility is comparable to the nitric acid etched silver foil SERS substrate. The surface morphology of the Ag/Cu film was observed by scanning electron micrography. The high SERS sensitivity of the film may be attributed to its special surface structure.

The thin films of cis-oleamide (OlA), steamide (StA), 2-undecylimidazole (UDIM), and 2-nonylbenzimidazole (NBIM) were prepared by spreading their solutions on Ag and KRS-5 substrate evaporating the solvent afterward, with the thickness in the range of 30–100 nm. The amphiphilic molecules in the multilayers were demonstrated to be highly organized by infrared reflection absorption and transmission spectroscopy. The orientation of the head group and the hydrocarbon chain of the amphiphiles in the film has been semiquantitatively evaluated. The C = O group of the amides, as well as the ring plane of imidazole and benzimidazole, has been proved to be parallel to the substrate surface. The CH stretching spectral features of the long hydrocarbon chain of the multilayers are quite different from the reported spectra of the stearate LB multilayer. The orientation of the hydrocarbon chain in the multilayers of StA and UDIM was evaluated to be inclined by about 30° from the substrate surface normal.