SURFACE-ENHANCED RAMAN-SCATTERING (SERS) AND SURFACE-ENHANCED RESONANCE RAMAN-SCATTERING (SERRS) ON HNO3-ROUGHENED COPPER FOIL

Copper foils for a Raman study were prepared by a chemical etching method with HNO3. These foils were found to exhibit a strong SERS effect. SERS or SERRS spectra of cobalt phthalocyanine, cystamine dihydrochloride, benzylamine, and p-thiocresol have been taken to illustrate the usefulness of this sample preparation technique. The enhancement effect of HNO3-roughened copper foil shows better thermal stability than that of vacuum-deposited Ag/CaF2 substrate. The HNO3-roughened copper foil seems to be a more easily prepared substrate system for SERS studies. There is a high potential that this technique could be used in studies of adsorption, molecular orientation, surface reaction, and surface catalysis at room or elevated temperatures.