Tunable surface enhanced Raman scattering of silver thin films by the graphene oxide

Silver thin films covered with a graphene oxide (GO) colloid layer were fabricated in this study. The coupling between GO and localized surface plasmons of the silver thin films was investigated by optical absorption and Raman scattering experiments. The absorption spectra showed that the intensity of the plasma edge peak at 320 nm decreased but the intensity of the interband transition peak at 350 nm was enhanced by an increase of the GO colloid concentration. The surface plasmon resonance attributed to the increased absorption of incident light by the GO layer caused an increase of the Raman scattering intensities. Theoretical calculations were performed for the surface plasmon resonance properties of the GO/silver thin films, and the results were in good agreement with the experiments.