Carbon-driven synthesis of bi-plasmonic Ag-Cu nanocomposite phosphate glasses

A simple method for the synthesis of Ag-Cu co-doped phosphate glasses displaying dual plasmon resonances is reported. The effective preparation is carried out by melting and heat treatment processes (ambient atmosphere) employing Ag₂O and CuO as metal nanoparticle precursors alongside carbon powder as reductant. Melt-quenched material shows optical absorption features characteristic of discrete silver and copper nanoclusters, while the photoluminescence is dominated by monovalent copper. Further thermal processing results in the development of a broad, extended bi-metallic plasmonic absorption. It is primarily influenced by silver nanoparticles, and appears consistent with the precipitation of the metals individually. The facile approach paves the way for further research on glasses with enhanced plasmonic properties.