Electrochemical Fabrication of Inverse Opals of Silver with Cyanide-Free Electrolytes

Silver inverse opals were prepared electrochemically using non-toxic water-ethanol rhodanic and sulfite electrolytes for silver plating. Electrochemical crystallization of silver occurred in the pores of opal matrices made of 350 nm polystyrene microspheres. Samples with the most uniform structure and lowest percentage of surface admixtures were obtained from rhodanic electrolytes. Reflectance optical spectra of the silver inverse opals with a high surface periodicity showed various plasmon excitation modes in a visible spectral range making the silver opals attractive for plasmonics.