Abstract
Fluorescence enhancement of CdTe nanocrystals through energy transfer to Ag nanocrystals is described, enabling us to fabricate highly luminescent quartz substrate. By immobilization of CdTe nanocrystals on Ag nanocrystals linked by dithiol molecules, fluorescence of CdTe nanocrystals is enhanced as compared to that of only CdTe nanocrystals. For example, the CdTe/Ag nanocrystals film linked by 1,5-pentanedithiol molecules exhibits ca. 3-fold fluorescence intensity of CdTe nanocrystals without Ag nanocrystals. Importantly, the fluorescence lifetime of this film decreased by complexation with Ag nanocrystals, indicating that the mechanism of fluorescence enhancement may be caused by energy transfer from CdTe to Ag nanocrystals. This effect depends on both distance between CdTe and Ag nanocrystals and types of metal nanocrystals. Fundamental understanding of enhancement effect by plasmonic nanocrystals paves the way toward the development of light-emitting devices, sensors, and energy conversion devices.
