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Title: Effect of Random Nanostructured Metallic Environments on Spontaneous Emission of HITC Dye
We have studied emission kinetics of HITC laser dye on top of glass, smooth Au films, and randomly structured porous Au nanofoams. The observed concentration quenching of luminescence of highly concentrated dye on top of glass (energy transfer to acceptors) and the inhibition of the concentration quenching in vicinity of smooth Au films were in accord with our recent findings. Intriguingly, the emission kinetics recorded in different local spots of the Au nanofoam samples had a spread of the decay rates, which was large at low dye concentrations and became narrower with increase of the dye concentration. We infer that in different subvolumes of Au nanofoams, HITC molecules are coupled to the nanofoams weaker or stronger. The inhibition of the concentration quenching in Au nanofoams was stronger than on top of smooth Au films. This was true for all weakly and strongly coupled subvolumes contributing to the spread of the emission kinetics. The experimental observations were explained using theoretical model accounting for change in the Förster radius caused by the strong energy transfer to metal.
Authors:
; ; ; ; ; ;
Award ID(s):
1830886 1856515 2000170
Publication Date:
NSF-PAR ID:
10274034
Journal Name:
Nanomaterials
Volume:
10
Issue:
11
Page Range or eLocation-ID:
2135
ISSN:
2079-4991
Sponsoring Org:
National Science Foundation
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