Luminescence Enhancement of CdS Quantum Dots in Glass by Ag plus Ion Exchange

Luminescence of CdS quantum dots (QDs) enhanced by the induction of Ag nanoparticles (NPs) in glasses was investigated. Ag+ ions diffused into glasses containing CdS QDs by ion exchange, then formed Ag NPs after subsequent heat treatment. Luminescence intensity of CdS QDs increased approximately three times when the ion-exchange duration was 1min, but was severely quenched when the duration was extended to 30min. Increasing the amount of Ag+ ions increased the number of Ag NPs and decreased the average distance between Ag NPs and CdS QDs. This decrease in the average distance induced the changes of luminescence intensity.