Comparison of SERS effectiveness of copper substrates prepared by different methods: what are the values of enhancement factors?

Surface-enhanced Raman scattering (SERS) spectroscopy is an analytical method for the detection of low amounts of analytes adsorbed on an appropriate coinage metal (Au, Ag, Cu) surface. Generally, the values of the enhancement factor are the highest on silver, lower on gold and relatively very low on copper. In this study, we have focused on the estimation of the enhancement factors of copper surface/substrates formed by different preparation procedures. The SERS activity of large electrochemically prepared substrates and colloidal systems is compared. The surface morphology of the large substrates was studied using scanning electron microscopy and atomic force microscopy. The size distribution of colloidal nanoparticles was monitored by dynamic light scattering. The values of enhancement factor are in both cases more than 105 for the FT-SERS spectra, demonstrating the fundamental role of nanostructured copper as a substrate material at the excitation wavelength (1064 nm) used. Copyright (C) 2011 John Wiley & Sons, Ltd.