Formation of Core-Shell Bimetallic Nanostructures in Alkali Silicate Glasses in the Course of Silver and Copper Ion Exchange and Thermal Treatment

Experimental data on the formation of the core-shell bimetallic spherical nanostructures in alkali silicate glasses is presented. The Ag-Cu and Cu-Ag core-shell bimetallic spherical nanostructures were formed in the near-surface glass layers by the successive Na+ -> Ag+ and Na+ -> Cu+ or Na+ -> Cu+ and Na+ -> Ag+ ion exchange and subsequent thermal treatment above the glass transition temperature. The optical density measurements have shown that the Ag-Cu core-shell nanostructures provide three plasmon resonances and the Cu-Ag core-shell nanostructures provide at least four plasmon resonances. Experimental results obtained are confirmed by computer simulation in the dipole quasistatic approximation.