The study of deposited silver particulate films by simple method for efficient SERS

We present a study on the preparation of silver particulate films by simple depositing colloidal solution on mica and highly oriented pyrolytic graphite (HOPG), respectively. The morphologies of the deposits were revealed by atomic force microscopic observations. It has been shown that the deposition can preserve the disperse state as well as aggregation feature existed in colloidal solution. Both silver particulate films were shown to be more activity than corresponding colloidal system for surface enhanced Raman scattering (SERS). Compared with that on mica, the silver film on HOPG not only represents excellent SERS activity, but also gives uniform spatial distribution for SERS signal measurement.