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Exceptionally stable blue phosphorescent organic light-emitting diodes


Blue phosphorescent organic light-emitting diodes (PhOLEDs) can deliver superior electroluminescence efficiencies than blue fluorescent OLEDs; however, their commercial debut has been delayed by short device lifetimes, especially for deep-blue PhOLEDs with Commission International de l’Eclairage y co-ordinates of less than 0.20. Here we report the use of new dopant and host materials to create a blue PhOLED device with a y co-ordinate of 0.197 and a long device lifetime of LT70 = 1,113 h [Initial luminance (L0) = 1,000 cd m–2]. Introducing bulky 3,5-di-tert-butyl-phenyl into the N-heterocyclic carbene moiety in the Pt(II) complex enhanced the photochemical stability of the high-lying metal-centred triplet state and prevented undesirable host–guest interactions, contributing to a longer device lifetime and higher colour purity. For the exciplex-forming host, the hole-transporting and electron-transporting host materials utilized a triphenylsilyl group for enhanced stability, which also improved the device lifetime.

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Fig. 1: Synthesis, spectrum and transient decay of the dopants.
Fig. 2: Chemical structure, frontier orbitals and exciplex characteristics of the host materials.
Fig. 3: Device performance of PhOLEDs.
Fig. 4: Intrinsic stability.

Data availability

The data that support the findings of this study are available from the corresponding authors on reasonable request. All data generated or analysed during this study are included in this published article and its Supplementary Information.


  1. Baldo, M., Thompson, M. E. & Forrest, S. High-efficiency fluorescent organic light-emitting devices using a phosphorescent sensitizer. Nature 403, 750–753 (2000).

    Article  ADS  Google Scholar 

  2. Segal, M. et al. Extrafluorescent electroluminescence in organic light-emitting devices. Nat. Mater. 6, 374 (2007).

    Article  ADS  Google Scholar 

  3. Uoyama, H., Goushi, K., Shizu, K., Nomura, H. & Adachi, C. Highly efficient organic light-emitting diodes from delayed fluorescence. Nature 492, 234–238 (2012).

    Article  ADS  Google Scholar 

  4. Nakanotani, H., Masui, K., Nishide, J., Shibata, T. & Adachi, C. Promising operational stability of high-efficiency organic light-emitting diodes based on thermally activated delayed fluorescence. Sci. Rep. 3, 1–6 (2013).

    Article  Google Scholar 

  5. Wong, M. & Zysman-Colman, E. Purely organic thermally activated delayed fluorescence materials for organic light-emitting diodes. Adv. Mater. 29, 1605444 (2017).

    Article  Google Scholar 

  6. Sun, J. W. et al. A fluorescent organic light‐emitting diode with 30% external quantum efficiency. Adv. Mater. 26, 5684–5688 (2014).

    Article  ADS  Google Scholar 

  7. Hatakeyama, T. et al. Ultrapure blue thermally activated delayed fluorescence molecules: efficient HOMO–LUMO separation by the multiple resonance effect. Adv. Mater. 28, 2777 (2016).

    Article  Google Scholar 

  8. Byeon, S. Y., Lee, D. R., Yook, K. S. & Lee, J. Y. Recent progress of singlet‐exciton‐harvesting fluorescent organic light‐emitting diodes by energy transfer processes. Adv. Mater. 31, 1803714 (2019).

    Article  Google Scholar 

  9. Klimes, K., Zhu, Z. Q. & Li, J. Efficient blue phosphorescent OLEDs with improved stability and color purity through judicious triplet exciton management. Adv. Funct. Mater. 29, 1903068 (2019).

    Article  Google Scholar 

  10. Holmes, R., Forrest, S., Tung, Y.-J., Kwong, R. & Brown, J. Blue organic electrophosphorescence using exothermic host–guest energy transfer. Appl. Phys. Lett. 82, 2422 (2003).

    Article  ADS  Google Scholar 

  11. Tang, M. et al. Dendritic luminescent gold(III) complexes for highly efficient solution-processable organic light-emitting devices. Angew. Chem. 125, 464–467 (2013).

    Article  ADS  Google Scholar 

  12. Hopkinson, M. N., Richter, C., Schedler, M. & Glorius, F. An overview of N-heterocyclic carbenes. Nature 510, 485–496 (2014).

    Article  ADS  Google Scholar 

  13. Chang, C. F. et al. Highly efficient blue‐emitting iridium(III) carbene complexes and phosphorescent OLEDs. Angew. Chem. Int. Ed. 47, 4542–4545 (2008).

    Article  Google Scholar 

  14. Lee, J. et al. Deep blue phosphorescent organic light-emitting diodes with very high brightness and efficiency. Nat. Mater. 15, 92–98 (2016).

    Article  ADS  Google Scholar 

  15. Cao, L. et al. Efficient and stable organic light-emitting devices employing phosphorescent molecular aggregates. Nat. Photon. 15, 230–237 (2021).

    Article  ADS  Google Scholar 

  16. Hang, X.-C., Fleetham, T., Turner, E., Brooks, J. & Li, J. Highly efficient blue-emitting cyclometalated platinum(II) complexes by judicious molecular design. Angew. Chem. Int. Ed. 52, 6753–6756 (2013).

    Article  Google Scholar 

  17. Li, G., Fleetham, T., Turner, E., Hang, X.-C. & Li, J. Highly efficient and stable narrow-band phosphorescent emitters for OLED applications. Adv. Opt. Mater. 3, 390–397 (2014).

    Article  Google Scholar 

  18. Zhang, Y., Lee, J. & Forrest, S. R. Tenfold increase in the lifetime of blue phosphorescent organic light-emitting diodes. Nat. Commun. 5, 1–7 (2014).

    Article  Google Scholar 

  19. Cho, H. et al. Phenylimidazole-based homoleptic iridium (III) compounds for blue phosphorescent organic light-emitting diodes with high efficiency and long lifetime. Org. Electron. 34, 91–96 (2016).

    Article  Google Scholar 

  20. Fleetham, T. B., Huang, L., Klimes, K., Brooks, J. & Li, J. Tetradentate Pt(II) complexes with 6-membered chelate rings: a new route for stable and efficient blue organic light emitting diodes. Chem. Mater. 28, 3276–3282 (2016).

    Article  Google Scholar 

  21. Song, W. & Lee, J. Degradation mechanism and lifetime improvement strategy for blue phosphorescent organic light-emitting diodes. Adv. Optical Mater. 5, 1600901 (2017).

    Article  Google Scholar 

  22. Kim, S. et al. Degradation of blue-phosphorescent organic light-emitting devices involves exciton-induced generation of polaron pair within emitting layers. Nat. Commun. 9, 1211 (2018).

    Article  ADS  Google Scholar 

  23. Maheshwaran, A. et al. High efficiency deep-blue phosphorescent organic light-emitting diodes with CIE x, y (≤ 0.15) and low efficiency roll-off by employing a high triplet energy bipolar host material. Adv. Funct. Mater. 28, 1802945 (2018).

    Article  Google Scholar 

  24. Jung, M., Lee, K. H., Lee, J. Y. & Kim, T. A bipolar host based high triplet energy electroplex for an over 10,000 h lifetime in pure blue phosphorescent organic light-emitting diodes. Mater. Horiz. 7, 559–565 (2020).

    Article  Google Scholar 

  25. Huh, J. S., Sung, M. J., Kwon, S. K., Kim, Y. H. & Kim, J. J. Highly efficient deep blue phosphorescent OLEDs based on tetradentate Pt(II) complexes containing adamantyl spacer groups. Adv. Funct. Mater. 31, 2100967 (2021).

    Article  Google Scholar 

  26. Su, S.-J., Cai, C., Takamatsu, J. & Kido, J. A host material with a small singlet–triplet exchange energy for phosphorescent organic light-emitting diodes: guest, host, and exciplex emission. Org. Electron. 13, 1937–1947 (2012).

    Article  Google Scholar 

  27. Wang, X. et al. Highly efficient deep‐blue electrophosphorescent Pt(II) compounds with non‐distorted flat geometry: tetradentate versus macrocyclic chelate Ligands. Adv. Funct. Mater. 27, 1604318 (2017).

    Article  Google Scholar 

  28. Ko, S.–B. et al. Organic light-emitting device and electronic apparatus including the same. European Patent 03544076 (2020).

  29. Park, Y. S. et al. Exciplex-forming co-host for organic light-emitting diodes with ultimate efficiency. Adv. Funct. Mater. 23, 4914–4920 (2013).

    Article  Google Scholar 

  30. Jankus, V., Chiang, C.-J., Dias, F. & Monkman, A. Deep blue exciplex organic light-emitting diodes with enhanced efficiency; P-type or E-type triplet conversion to singlet excitons? Adv. Mater. 25, 1455–1459 (2013).

    Article  Google Scholar 

  31. Choi, S. et al. Optimized structure of silane-core containing host materials for highly efficient blue TADF OLEDs. J. Mater. Chem. C 5, 6570–6577 (2017).

    Article  Google Scholar 

  32. Choi, K. H., Lee, K. H., Lee, J. Y. & Kim, T. Simultaneous achievement of high efficiency and long lifetime in deep blue phosphorescent organic light‐emitting diodes. Adv. Opt. Mater. 7, 1901374 (2019).

    Article  Google Scholar 

  33. Costa Rubén, D. et al. Efficient and long-living light-emitting electrochemical cells. Adv. Funct. Mater. 20, 1511–1520 (2010).

    Article  Google Scholar 

  34. Kang, S., Kim, T. & Lee, J. Y. New design strategy for chemically-stable blue phosphorescent materials: improving the energy gap between T1 and 3MC states. Phys. Chem. Chem. Phys. 23, 3543–3551 (2021).

    Article  Google Scholar 

  35. Wang, Y., Peng, Q. & Shuai, Z. A computational scheme for evaluating the phosphorescence quantum efficiency: applied to blue-emitting tetradentate Pt(II) complexes. Mater. Horiz. 9, 334–341 (2022).

    Article  Google Scholar 

  36. Li, G. et al. N-Heterocyclic carbene-tetradetate Pd(II) complexes for deep-blue phosphorescent materials. Organometallics 40, 472–481 (2021).

    Article  Google Scholar 

  37. Wang, Y., Yun, J. H., Wang, L. & Lee, J. Y. High triplet energy hosts for blue organic light-emitting diodes. Adv. Funct. Mater. 31, 2008332 (2021).

    Article  Google Scholar 

  38. Mollere, P. & Hoffmann, R. Augmented silicon–carbon bond strengths via dσ hyperconjugation. J. Am. Chem. Soc. 97, 3680–3682 (1975).

    Article  Google Scholar 

  39. Kim, S. Y. et al. Organic light-emitting diodes with 30% external quantum efficiency based on a horizontally oriented emitter. Adv. Funct. Mater. 23, 3896–3900 (2013).

    Article  Google Scholar 

  40. Lee, S., Kim, K. H., Limbach, D., Park, Y. S. & Kim, J. J. Low roll-off and high efficiency orange organic light emitting diodes with controlled co-doping of green and red phosphorescent dopants in an exciplex forming co-host. Adv. Funct. Mater. 23, 4105–4110 (2013).

    Article  Google Scholar 

  41. Lee, S. et al. High efficiency and non-color-changing orange organic light emitting diodes with red and green emitting layers. Org. Electron. 14, 1856–1860 (2013).

    Article  Google Scholar 

  42. Sasabe, H. & Kido, J. Multifunctional materials in high-performance OLEDs: challenges for solid-state lighting. Chem. Mater. 23, 621–630 (2011).

    Article  Google Scholar 

  43. Seino, Y., Sasabe, H., Pu, Y. J. & Kido, J. High-performance blue phosphorescent OLEDs using energy transfer from exciplex. Adv. Mater. 26, 1612–1616 (2014).

    Article  Google Scholar 

  44. Lee, J. H. et al. An exciplex forming host for highly efficient blue organic light emitting diodes with low driving voltage. Adv. Funct. Mater. 25, 361–366 (2015).

    Article  Google Scholar 

  45. Dennington, R., Keith, T. & Millam, J. GaussView Version 5.0 (Semichem, 2016).

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Y.Y. (Ewha Womans’ Univ.) acknowledges the Midcareer Research Program (NRF-2019R1A2C2003969), the Basic Research Laboratory Program (NRF-2019R1A4A1029052) and the Nano Material Technology Development Program (NRF-2021M3D1A2049323) through the National Research Foundation grants funded by the Ministry of Science, Information and Communication Technology, and Future Planning of Korea.

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Authors and Affiliations



J.S., S.K., S.-B.K., H.A., D.S. and Y.Y. analysed the data and wrote the manuscript under supervision of C.C. and S.K., J.S., Y.L. and S.-B.K. designed the dopant molecule. S.-B.K. and S.K. synthesized and characterized the dopant material. H.A. designed the host molecule. H.U. and H.A. synthesized and characterized the host materials under supervision of S.-H.H. J.S. performed exciplex analysis. S.K. conducted theoretical calculations for all of the materials. J.S. and Y.L. analysed the device data. P.J. carried out device fabrication. Y.Y. coordinated the research at Ewha Womans University. D.S. performed the degradation experiments. All authors discussed the progress of research and reviewed the manuscript.

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Correspondence to Changwoong Chu or Sunghan Kim.

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Nature Photonics thanks Marc Baldo, Jian Li and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Synthesis, Experimental, Methods for Device fabrication and measurements, Supplementary Figs. 1–26, Tables 1–9 and References.

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Sun, J., Ahn, H., Kang, S. et al. Exceptionally stable blue phosphorescent organic light-emitting diodes. Nat. Photon. 16, 212–218 (2022).

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