The SERS study of graphene deposited by gold nanoparticles with 785Â nm excitation

Surface enhanced Raman scattering (SERS) of graphene deposited by the Au nanoparticles were investigated with the 785 nm excitation. The SERS spectra are used to extract information of graphene. It was shown that the artificial defects were effectively induced by depositing Au nanoparticles on graphene surface. Meanwhile, the Au nanoparticle can quench the fluorescence of substrate and enhance the Raman signals of graphene drastically. The adatom-induced defects in graphene cause a significant Raman intensity in D and D′ band. This shed light on the understanding of the structural characteristics of graphene-based nanocomposite and the interaction between graphene and metal adatoms.

In this Letter we present the investigation of surface enhanced Raman scattering (SERS) spectra of graphene deposited by the Au nanoparticls on SiO2/Si substrate with the 785 nm excitation. We show that SERS technique is a promising approach which cannot only induce the morphological defect but also quench the fluorescence background of the SiO2/Si and enhance the Raman signals of the graphene. It was shown that adatom-induced defects by gold island film in graphene cause a significant intensity in the Raman D band associated with intervalley electron scattering. So do the D′ band and 2D. This shed light on the understanding of the structural characteristics of graphene based nanocomposites and the interaction between graphene and metal nanoparticles. 146Highlights► The surface enhanced Raman scattering spectra of graphene by 785 nm was obtained. ► The artificial defects were effectively induced by Au nanoparticles on graphene surface. ► The Au nanoparticle can quench the fluorescence of substrate SiO2/Si. ► The surface plasmon of Au nanoparticles enhanced the Raman signals of graphene drastically. ► The adatom-induced defects in graphene cause a significant Raman intensity in D and D′ band.