Tracking the Energy Flow on Nanoscale via Sample-Transmitted Excitation Photoluminescence Spectroscopy.
Tracking the energy flow in nanoscale materials is an important yet challenging goal. Experimental methods for probing the intermolecular energy transfer (ET) are often burdened by the spectral crosstalk between donor and acceptor species, which complicates unraveling their individual contributions. This issue is particularly prominent in inorganic nanoparticles and biological macromolecules featuring broad absorbing profiles. Here, we demonstrate a general spectroscopic strategy for measuring the ET efficiency between nanostructured or molecular dyes exhibiting a significant donor-acceptor spectral overlap. The reported approach is enabled through spectral shaping of the broadband excitation light with solutions of donor molecules, which inhibits the excitation of respective donor species in the sample. The resulting changes in the acceptor emission induced by the spectral modulation of the excitation beam are then used to determine the quantum efficiency and the rate of ET processes between arbitrary fluorophores (molecules, nanoparticles, polymers) with high accuracy. The feasibility of the reported method was demonstrated using a control donor-acceptor system utilizing a protein-bridged Cy3-Cy5 dye pair and subsequently applied for studying the energy flow in a CdSe560-CdSe600binary nanocrystal film.
The Center for Photochemical Sciences, ‡Department of Physics, and §Department of Chemistry, Bowling Green State University , Bowling Green, Ohio 43403, United States.
Pavel
P
Moroz
The Center for Photochemical Sciences, ‡Department of Physics, and §Department of Chemistry, Bowling Green State University , Bowling Green, Ohio 43403, United States.
Natalia
N
Razgoniaeva
The Center for Photochemical Sciences, ‡Department of Physics, and §Department of Chemistry, Bowling Green State University , Bowling Green, Ohio 43403, United States.
Yufan
Y
He
The Center for Photochemical Sciences, ‡Department of Physics, and §Department of Chemistry, Bowling Green State University , Bowling Green, Ohio 43403, United States.
Gregory
G
Jensen
The Center for Photochemical Sciences, ‡Department of Physics, and §Department of Chemistry, Bowling Green State University , Bowling Green, Ohio 43403, United States.
Holly
H
Eckard
The Center for Photochemical Sciences, ‡Department of Physics, and §Department of Chemistry, Bowling Green State University , Bowling Green, Ohio 43403, United States.
H Peter
HP
Lu
The Center for Photochemical Sciences, ‡Department of Physics, and §Department of Chemistry, Bowling Green State University , Bowling Green, Ohio 43403, United States.
Mikhail
0000-0002-8638-2972
M
Zamkov
FRET; bleed through; crosstalk; energy transfer; nanocrystals