SURFACE-ENHANCED RAMAN-SCATTERING FROM CHLORIDE ON COPPER ELECTRODES

A new method for the preparation of SERS active Cu electrode surfaces with high enhancement factors, which enable the observation of high qu ality spectra in the low-frequency region at different chloride concen trations, is proposed. Low-frequency modes at 160 and 145 cm-1 are att ributed to Cu-Cu vibrations by isotopic (Cu-63/Cu-65) frequency shift. Qualitative agreement with predictions of the dipole-dipole coupling model are observed for Cu-Cl mode frequency dependence on Cl- ion conc entration. A linear frequency nu(Cu-Cl) dependence on relative integra ted SERS intensity for deactivated Cu electrodes has been found. Diffe rences in concentration behaviour of the Cu-Cl mode for activated and deactivated Cu electrodes are discussed.