SERS‐active substrates based on silvered porous silicon

Silver nanoparticles are obtained through immersion plating of porous Si in AgNO3 solutions and thermal decomposition of Ag nitrate in oxidized pSi. The efficiency of nanostructures as Surface Enhanced Raman Scattering substrates is checked on a Cyanine dye evidencing detectable concentrations as low as 107 M. The substrate efficiency is strictly related to the Ag particle morphology, which could yield to either Localized Surface Plasmons coupled to individual particles or to inter-particle short-range interaction