Formation of argentic clusters and small Ag nanoparticles in soda-lime silicate glass

The formation of argentic clusters and very small Ag nanoparticles of 0.5 to 2 nm size in commercial soda-lime glass silver-doped by Ag/Na ion exchange in a mixed nitrate melt has been studied by electron microscopy and EXAFS. Particles formation was induced already during the ion exchange procedure, or by subsequent ion irradiation with 1.5 MeV He⁺ or 3 MeV Au⁺. The presence of nanoparticles was also macroscopically revealed by their surface plasmon resonance. The structural characterization indicates that specific configurations of silver oxide-like structures, so-called argentic clusters, are involved in the initial stage of nanoparticles formation.