Acceptor Concentration Dependence of Forster Resonance Energy Transfer Dynamics in Dye-Quantum Dot Complexes

作者:Dworak Lars; Matylitsky Victor V; Ren Ting; Basche Thomas; Wachtveitl Josef*
来源:Journal of Physical Chemistry C, 2014, 118(8): 4396-4402.
DOI:10.1021/jp409807x

摘要

The dynamics of the photoinduced Forster resonance energy transfer (FRET) in a perylene diimide-quantum dot organic-inorganic hybrid system has been investigated by femtosecond time-resolved absorption spectroscopy. The bidentate binding of the dye acceptor molecules to the surface of CdSe/CdS/ZnS multishell quantum dots provides a well-defined dye-QD geometry for which the efficiency of the energy transfer reaction can be easily tuned by the acceptor concentration. In the experiments, the spectral characteristics of the chosen FRET pair facilitate a selective photoexcitation of the quantum dot donor. Moreover, the acceptor related transient absorption change that occurs solely after energy transfer is utilized for the determination of the energy transfer dynamics. Our time-resolved measurements demonstrate that an increase of the acceptor concentration accelerates the donor-acceptor energy transfer. Considering a Poisson distribution of acceptor molecules per quantum dot, the dependence of the energy transfer rate on its mean value is linear. The results of the presented spectroscopic experiments allow for determining the relative and absolute acceptor/donor ratio in the investigated FRET system without any parameters intrinsic to Forster theory.

  • 出版日期2014-2-27