High-efficiency electroluminescence and amplified spontaneous emission from a thermally activated delayed fluorescent near-infrared emitter


Near-infrared organic light-emitting diodes and semiconductor lasers could benefit a variety of applications including night-vision displays, sensors and information-secured displays. Organic dyes can generate electroluminescence efficiently at visible wavelengths, but organic light-emitting diodes are still underperforming in the near-infrared region. Here, we report thermally activated delayed fluorescent organic light-emitting diodes that operate at near-infrared wavelengths with a maximum external quantum efficiency of nearly 10% using a boron difluoride curcuminoid derivative. As well as an effective upconversion from triplet to singlet excited states due to the non-adiabatic coupling effect, this donor–acceptor–donor compound also exhibits efficient amplified spontaneous emission. By controlling the polarity of the active medium, the maximum emission wavelength of the electroluminescence spectrum can be tuned from 700 to 780 nm. This study represents an important advance in near-infrared organic light-emitting diodes and the design of alternative molecular architectures for photonic applications based on thermally activated delayed fluorescence.

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Fig. 1: Steady-state PL properties of the boron difluoride curcuminoid derivative.
Fig. 2: Time-resolved PL of the curcuminoid derivative.
Fig. 3: Properties of the NIR TADF OLEDs.
Fig. 4: ASE properties of curcuminoid derivative in thin films.


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The authors thank H. Sasabe and K. Tokumaru for discussions. A.S.D.S., T.K., Y.T., J.C.R. and C.A. acknowledge support by JST ERATO grant no. JPMJER1305, Japan. The work at Georgia Tech was supported by the Georgia Research Alliance and Georgia Tech's College of Sciences. A.D., F.F., E.Z. and D.Y. acknowledge support by the French National Research Agency (ANR) (‘Chalcones’ project, ANR-14-CE05-0035-01). J.W.W. and A.D. were supported by the Ministry of Science, ICT and Future Planning, Korea (2017R1E1A1A01075394 and 2014M3A6B3063706).

Author information

A.D., J.-C.R. and C.A. initiated, designed and supervised the research project and experiments. D.Y. synthesized the curcuminoid derivative under the supervision of E.Z. and F.F. G.C. performed electrochemistry of the dye. X.-K.C. carried out the quantum-chemical calculations under the supervision of J.-L.B. Characterization of the steady-state and time-resolved photophysical properties was carried out by D.-H.K., A.D., A.S.D.S. and E.C. The results were analysed with the help of Y.T., J.W.W., F.F., J.-C.R. and C.A. Characterization of the molecular orientation of emitting dyes in the thin films was performed by L.Z. and T.K. All device fabrication and characterization was carried out by D.-H.K. under the supervision of J.-C.R. and C.A. The manuscript was written by J.-C.R., A.D. and X.-K.C. All authors discussed the results and contributed to writing the manuscript.

Correspondence to Anthony D’Aléo or Jean-Charles Ribierre or Chihaya Adachi.

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Kim, D., D’Aléo, A., Chen, X. et al. High-efficiency electroluminescence and amplified spontaneous emission from a thermally activated delayed fluorescent near-infrared emitter. Nature Photon 12, 98–104 (2018). https://doi.org/10.1038/s41566-017-0087-y

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