10.1002/anie.201914249
Angewandte Chemie International Edition
COMMUNICATION
OLEDs were -1.2 × 10-2 for (–)-(S)-Cz-Ax-CN and +1.4 × 10-2 for
(+)-(R)-Cz-Ax-CN, respectively, which were larger than the gEL
values of most TADF enantiomers based on chiral perturbation
strategy. The results further confirmed that by our chiral emitting
skeleton strategy based on dual fluorescent cores, chiral TADF
materials with both high efficiencies and intense CPEL of large
gEL values could be conveniently obtained. This is also the first
CP-OLEDs with efficient blue CPEL based on TADF enantiomers.
Keywords: CP-OLEDs • TADF • axial enantiomer • blue
electroluminescence • circularly polarized electroluminescence
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(+)-(R)-Cz-Ax-CN
(+)-(R)-Cz-Ax-CN
(−)-(S)-Cz-Ax-CN
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Wavelength (nm)
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Luminance (cd/m2)
Wavelength (nm)
Figure 6. The energy diagram (a) and performance of CP-OLEDs based on (–)-
(S)-Cz-Ax-CN and (+)-(R)-Cz-Ax-CN. (b) EQE-luminance characteristics. Inset:
EL spectra of the devices at 6 V. (c) The gEL values of the devices as a function
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In summary, we proposed a chiral emitting skeleton strategy
for designing axial TADF enantiomers with CPL activities, and
thus fabricating CP-OLEDs with high EQEs and large gEL values.
The enantiomers with rigid chiral axis obtained by coupling two
fluorophores exhibited both intramolecular π-conjugated CT and
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CPEL with gEL values of -1.2 × 10-2 and +1.4 × 10-2, respectively,
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presented herein provides
a promising design for chiral
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Acknowledgements
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We thank the National Natural Science Foundation of China
(21871272, 91956119, 21521002), and the Youth Innovation
Promotion Association CAS (No. 2019034) for financial supports.
We also thank Dr. F. Song for collecting the CPEL signals.
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