Surface-enhanced Raman scattering (SERS) technology can amplify the Raman signal due to excited localized surface plasmon (LSP) from SERS substrates, and the properties of the substrate play a decisive role for SERS sensing. Several methods have been developed to improve the performance of the substrate by surface modification. Here, we reported a surface modification method to construct carbon-coated nanoporous gold (C@NPG) SERS substrate. With surface carbon-assistant, the SERS ability of nanoporous gold (NPG) seriously improved, and the detection limit of the dye molecule (crystal violet) can reach 10-13 M. Additionally, the existence of carbon can avoid the deformation of the adsorbed molecule caused by direct contact with the NPG. The method that was used to improve the SERS ability of the NPG can be expanded to other metal structures, which is a convenient way to approach a high-performance SERS substrate.
Keywords: carbon assistance; crystal violet; enhancement factor; finite difference time domain; nanoporous gold; surface-enhanced Raman scattering.