AI Article Synopsis
- Supramolecular assemblies of organic dyes known as J-aggregates exhibit narrowband photoluminescence, but traditionally have low quantum yields.
- Recent research shows that cyanine J-aggregates can achieve significantly higher photoluminescence quantum yields (from 5% to 60%) in specific blend solutions of water and alkylamines at room temperature.
- Time-resolved studies indicate that this increase in efficiency is due to longer exciton lifetimes and a suppression of non-radiative processes, while small-angle neutron scattering highlights the importance of a distinct water/amine interface for optimal J-aggregate formation.
Article Abstract
Supramolecular assemblies from organic dyes forming J-aggregates are known to exhibit narrowband photoluminescence with full-width at half maximum of ≈9 nm (260 cm). Applications of these high color purity emitters, however, are hampered by the rather low photoluminescence quantum yields reported for cyanine J-aggregates, even when formed in solution. Here, it is demonstrated that cyanine J-aggregates can reach an order of magnitude higher photoluminescence quantum yield (increase from 5% to 60%) in blend solutions of water and alkylamines at room temperature. By means of time-resolved photoluminescence studies, an increase in the exciton lifetime as a result of the suppression of non-radiative processes is shown. Small-angle neutron scattering studies suggest a necessary condition for the formation of such highly emissive J-aggregates: the presence of a sharp water/amine interface for J-aggregate assembly and the coexistence of nanoscale-sized water and amine domains to restrict the J-aggregate size and solubilize monomers, respectively.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7887577 | PMC |
| http://dx.doi.org/10.1002/advs.201903080 | DOI Listing |
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