Energy Transfer from CdSe/CdS Nanorods to Amorphous Carbon

Institute of Physical Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany.
Nano Letters (Impact Factor: 12.94). 12/2011; 11(12):5179-83. DOI: 10.1021/nl202370q
Source: PubMed

ABSTRACT Semiconductor nanocrystals placed nearby a metal film significantly change their optical properties. In this work, we examine the change in fluorescence intensity, lifetime, and blinking behavior of individual CdSe/CdS nanorods close to a 9 nm thick amorphous carbon film. Energy transfer between the donor and acceptor was investigated in detail yielding a R(-4) distance dependence for the nanorod-carbon system. The Förster critical distance was determined to be R0=24.9 nm, which is nearly identical with the theoretical value of 24.8 nm predicted by the classical approach. Additionally, antibunching measurements were performed in order to prove the presence of single isolated emitters.

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