Real-time analysis of the "plasmonic diluent" effect: Probing Ag nanoparticle growth rate via Dy³⁺ photoluminescence quenching

In situ optical microspectroscopy has been applied for the real-time monitoring of the recently established "plasmonic diluent" effect. Concurrent absorption and photoluminescence measurements were performed as a function of time for an Ag-Dy co-doped glass at elevated temperatures. The isothermal kinetic analysis reveals: (i) a Dy³⁺ photoluminescence quenching; and (ii) development of surface plasmon resonance of Ag nanoparticles. A method for monitoring the Ag nanoparticle growth rate based on the time-dependent Dy³⁺ photoluminescence decrease is suggested. Dysprosium ions are proposed to act as luminescent probes of metal nanoparticle growth as a consequence of the rare-earth de-excitation via the "plasmonic diluent" effect.