The effect of size on the surface enhanced Raman scattering property of SiO2@PDA@AgNP core-shell-satellite nanocomposite

Here we report SiO2@PDA@AgNP core-shell-satellite nanostructure as a new SERS substrate. This is prepared by in situ deposition of silver nanoparticles (AgNP) on the surface of polydopamine (PDA) coated silica nanoparticles (SiO2) with different sizes. The characterization of the samples along with normalization of the SERS spectra revealed a quantitative correlation between the enhancement effect of SERS and the mean diameters of the SiO2 nanoparticles. These results may provide a potential correlation between surface distribution of AgNP nanoparticles and SERS enhancement property.