Abstract: Based on silicon nanoporous pillar array(Si-NPA), an active substrate(Ag/Si-NPA) with strong surface-enhanced Raman scattering(SERS) effect was prepared by an immersion plating method. The surface morphology and structure of Ag/Si-NPA were characterized by field-emission scanning electron microscopy(FESEM) and transmission electron microscopy(TEM). Choosing two important biological dyes, Rhodamine 6G(R6G) and crystal violet(CV), as the target materials and adopting three different adsorbing procedures, the SERS spectra for R6G and CV co-adsorbed on Ag/Si-NPA were detected. It was found that the Raman peaks for CV were completely glossed over by that of R6G when the concentration of both solutions was 10^-7 mol/L, no matter what adsorbing procedure was adopted. The phenomenon was explained based on the experimental conditions and results. When the solution concentrations for R6G and CV were chosen as 10^-9 and 10^-7 mol/L, two groups of characteristic SERS peaks with good separation, well-matched relative intensity and high resolution, corresponding to R6G and CV, respectively, were obtained. Such a SERS spectrum was very helpful for predigesting the indexing and estimating procedure about the characteristic peaks. Our results might provid an investigable route for realizing the SERS detection of multi-dye labeled complex bio-molecule systems.

Key words: Rhodamine 6G(R6G), Crystal violet(CV), Silicon nanoporous pillar array(Si-NPA), Ag/Si-NPA, Surface-enhanced Raman scattering(SERS), Co-adsorption