Ultraviolet-visible and surface-enhanced Raman scattering spectroscopy studies on ruthenium phthalocyanine monolayer films formed on terephthalonitrile-modified silver substrates

A self-assembled monolayer film(SAM) of ruthenium phthalocyanine(RuPc) fabricated on a silver substrate premodified with an SAM of terephthalonitrile(TPN) was studied by means of surf ace-enhanced Raman scattering (SERS) and ultraviolet-visible (UV-Vis) spectroscopies. TPN was used as a ligand to link RuPc since it can not only modify the silver substrate but also deliver the nitrile groups protruding from the silver surface. Therefore, we can explore the relationship between the structure and the orientation of RuPc and the TPN-modified substrate. The UV-Vis spectra indicate a strong interaction between RuPc and TPN in the composite film. The result is further confirmed by the SERS spectra of RuPc-TPN SAM. in which the vibrational bands arising from both the RuPc and TPN moieties appear clearly. indicating that the RuPc is successfully assembled on the TPN film.