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Thermally Activated Delayed Fluorescence in a Y₃ N@C₈₀ Endohedral Fullerene: Time-Resolved Luminescence and EPR Studies.

ABSTRACT: The endohedral fullerene Y₃ N@C₈₀ exhibits luminescence with reasonable quantum yield and extraordinary long lifetime. By variable-temperature steady-state and time-resolved luminescence spectroscopy, it is demonstrated that above 60 K the Y₃ N@C₈₀ exhibits thermally activated delayed fluorescence with maximum emission at 120 K and a negligible prompt fluorescence. Below 60 K, a phosphorescence with a lifetime of 192±1 ms is observed. Spin distribution and dynamics in the triplet excited state is investigated with X- and W-band EPR and ENDOR spectroscopies and DFT computations. Finally, electroluminescence of the Y₃ N@C₈₀ /PFO film is demonstrated opening the possibility for red-emitting fullerene-based organic light-emitting diodes (OLEDs).

SUBMITTER: Zalibera M

PROVIDER: S-EPMC5751888 | biostudies-literature |

REPOSITORIES: biostudies-literature

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