Electrochemically formed inverse opals of silver

Silver inverse opals have been prepared electrochemically using a number of water-ethanol acidic or alkaline electrolytes. Opal matrices made of polystyrene microspheres of 420 nm diameter were used as templates. Compositions of electrolytes and conditions of syntheses have been optimized according to cyclic voltammetry and stability window of silver complexes during the experiments. Samples with the most uniform structure have been deposited from the iodous electrolyte. At the same time, the list percentage of surface admixtures observed for the opals formed from the rhodanide electrolyte using X-ray photoelectron spectroscopy (XPS). Reflectance optical spectra of the silver inverse opals measured with angles of incidence of 8 - 64° have shown various plasmon excitation modes in a visible spectral range according to the Bragg effect making the silver opals attractive for the Surface-Enhanced Raman Spectroscopy (SERS).