Study of experimental parameters for improved adsorbate detectability in SERS using etched silver substrates

In order to understand the experimental parameters that influence the optimum surface-enhanced Raman scattering (SERS) signals obtained using silver foils etched by nitric acid as substrate, silver surfaces were analysed by x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and SERS. The best conditions to obtain the strongest SERS signals when the foils are spotted with 9-aminoacridine chlorhydrate solutions are determined by comparison of XPS, SEM and SERS results. An adequate etch time for fine-scale silver protrusions superimposed on the coarser silver surface is highlighted.