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RESEARCH PRODUCT
Solvatochromism Unravels the Emission Mechanism of Carbon Nanodots
Peter SchallFabrizio MessinaEmanuele MarinoAlice SciortinoAlice SciortinoBart Van DamMarco Cannassubject
Range (particle radiation)PhotoluminescenceChemistrySettore FIS/01 - Fisica SperimentaleSolvatochromismQuantum yield02 engineering and technologyElectron010402 general chemistry021001 nanoscience & nanotechnologyPhotochemistryCondensed Matter::Mesoscopic Systems and Quantum Hall Effect01 natural sciencesFluorescence0104 chemical sciencesCondensed Matter::Materials ScienceChemical physicsAtomic electron transitionGeneral Materials ScienceSpontaneous emissionCarbon dots photoluminescence nanomaterialsPhysical and Theoretical Chemistry0210 nano-technologydescription
High quantum yield, photoluminescence tunability, and sensitivity to the environment are hallmarks that make carbon nanodots interesting for fundamental research and applications. Yet, the underlying electronic transitions behind their bright photoluminescence are strongly debated. Despite carbon-dot interactions with their environment should provide valuable insight into the emitting transitions, they have hardly been studied. Here, we investigate these interactions in a wide range of solvents to elucidate the nature of the electronic transitions. We find remarkable and systematic dependence of the emission energy and kinetics on the characteristics of the solvent, with strong response of the photoexcited dots to hydrogen bonding. These findings suggest that the fluorescence originates from the radiative recombination of a photoexcited electron migrated to surface groups with holes left in the valence band of the crystalline core. Furthermore, the results demonstrate the fluorescence tunability to inherently derive from dot-to-dot polydispersity, independent of solvent interactions.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2016-09-01 | The Journal of Physical Chemistry Letters |