Exciton annihilation and diffusion length in disordered multichromophoric nanoparticles
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F24%3A10491579" target="_blank" >RIV/00216208:11320/24:10491579 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=sM3NCRlZyh" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=sM3NCRlZyh</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1039/d4nr00325j" target="_blank" >10.1039/d4nr00325j</a>
Alternative languages
Result language
angličtina
Original language name
Exciton annihilation and diffusion length in disordered multichromophoric nanoparticles
Original language description
Efficient exciton transport is the essential property of natural and synthetic light-harvesting (LH) devices. Here we investigate exciton transport properties in LH organic polymer nanoparticles (ONPs) of 40 nm diameter. The ONPs are loaded with a rhodamine B dye derivative and bulky counterion, enabling dye loadings as high as 0.3 M, while preserving fluorescence quantum yields larger than 30%. We use time-resolved fluorescence spectroscopy to monitor exciton-exciton annihilation (EEA) kinetics within the ONPs dispersed in water. We demonstrate that unlike the common practice for photoluminescence investigations of EEA, the non-uniform intensity profile of the excitation light pulse must be taken into account to analyse reliably intensity-dependent population dynamics. Alternatively, a simple confocal detection scheme is demonstrated, which enables (i) retrieving the correct value for the bimolecular EEA rate which would otherwise be underestimated by a typical factor of three, and (ii) revealing minor EEA by-products otherwise unnoticed. Considering the ONPs as homogeneous rigid solutions of weakly interacting dyes, we postulate an incoherent exciton hoping mechanism to infer a diffusion constant exceeding 0.003 cm(2) s(-1) and a diffusion length as large as 70 nm. This work demonstrates the success of the present ONP design strategy at engineering efficient exciton transport in disordered multichromophoric systems. The unbiased fluorescence monitoring of exciton-exciton annihilation kinetics reveals an exciton diffusion length exceeding 70 nm in highly concentrated, disordered, dye-loaded organic nanoparticles.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10301 - Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)
Result continuities
Project
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Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2024
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Nanoscale
ISSN
2040-3364
e-ISSN
2040-3372
Volume of the periodical
16
Issue of the periodical within the volume
24
Country of publishing house
GB - UNITED KINGDOM
Number of pages
14
Pages from-to
11550-11563
UT code for WoS article
001245061200001
EID of the result in the Scopus database
2-s2.0-85196111002