Raman spectroscopy of copper phthalocyanine/graphene and 2,3,5,6‐tetrafluoro‐tetracyano‐quino‐dimethane/graphene interfaces

The copper phthalocyanine and 2,3,5,6‐tetrafluoro‐tetracyano‐quino‐dimethane molecules adsorbed on the copper and single‐layer graphene‐modified copper surfaces have been investigated using Raman and X‐ray photoelectron spectroscopy. The adsorbed amounts for both molecules on the two different substrates are almost comparable as confirmed by the C 1s and N 1s core level X‐ray photoelectron spectra. Raman signal enhancement has been observed for both molecules when they are adsorbed on the graphene surface. The strongest chemical interaction is observed between the 2,3,5,6‐tetrafluoro‐tetracyano‐quino‐dimethane and copper substrate. Based on the Raman and X‐ray photoelectron spectroscopic data, the mechanism of the graphene‐enhanced Raman scattering is discussed, which might greatly rely on the unique electronic properties of graphene.