Weak emissive D-O-A organic phosphor: Exceptional matrix-free sensitization in MR-TADF OLEDs

Lulin Xu; Shuai Xiao; Ying Yang; Han Si; Changsheng Shi; Huaiyi Ding; Ning Sun; Liming Ding; Junqiao Ding

doi:10.59717/j.xinn-mater.2026.100210

The Innovation Materials > 2026 Vol. 4 > No. 2 > 100210

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Weak emissive D-O-A organic phosphor: Exceptional matrix-free sensitization in MR-TADF OLEDs

1.
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education; School of Chemical Science and Technology, Yunnan University; National Center for International Joint Research of Photoelectronic Energy Materials and Application, Kunming 650091, China
2.
Southwest United Graduate School, Kunming 650092, China
3.
School of Physics and Astronomy, Yunnan University, Kunming 650091, China
4.
School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China
5.
These authors contributed equally

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Corresponding authors: sihan94720@outlook.com (H.S.); ding@gdut.edu.cn (L.D.); dingjunqiao@ynu.edu.cn (J.D.)
Received Date: November 12, 2025

Accepted Date: March 04, 2026

Published Online: March 04, 2026

The Innovation Materials 4(2), https://doi.org/10.59717/j.xinn-mater.2026.100210 | Cite this article

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PUBLIC SUMMARY

PUBLIC SUMMARY
1. A weakly emissive D–O–A organic phosphor is developed to act as an efficient sensitizer for MR–TADF emitters.
  
  High-performance narrowband electroluminescence is achieved ranging from sky blue to red.
  
  The exceptional results break a habitual thinking that the best sensitizer should be the best emitter.

ABSTRACT

ABSTRACT

D-O-A organic phosphors showing strong aggregation-induced room-temperature phosphorescence (RTP) have been successfully demonstrated as the ideal matrix-free sensitizers for MR-TADF OLEDs. However, weak emissive ones still remain unexplored according to a habitual thinking that the best sensitizer should be the best emitter. Herein, a poor RTP emitter named RTP-D3 is newly developed based on carbazole as the donor, triazine as the acceptor and oxygen as the bridge. In spite of the extremely low photoluminescence quantum yield, RTP-D3 can sensitize the terminal MR-TADF molecules effectively and universally because of favored π-π and C-H∙∙∙π intermolecular interactions among triazine moieties and thus a balanced charge transport. Consequently, high performance sky-blue, green, yellow and red narrowband electroluminescence is realized together with a state-of-art external quantum efficiency of 22.2% (49.2 cd/A, 55.2 lm/W), 31.5% (105.1 cd/A, 113.9 lm/W), 32.9% (112.4 cd/A, 133.3 lm/W) and 29.7% (55.4 cd/A, 66.9 lm/W) as well as Commission Internationale de l’Eclairage (CIE) coordinates of (0.12, 0.48), (0.26, 0.70), (0.45, 0.54) and (0.61, 0.39), respectively. The exceptional results break a conventional blind spot about RTP sensitizer, highlighting that the less emissive D-O-A organic phosphors are also suitable for the best matrix-free sensitization in MR-TADF OLEDs.
- MR-TADF OLEDs /
- D-O-A organic phosphor /
- matrix-free sensitization /
- aggregation-induced room-temperature phosphorescence /
- strong emitter Vs weak emitter

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REFERENCES

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Xu L., Xiao S., Yang Y., et al. (2026). Weak emissive D-O-A organic phosphor: Exceptional matrix-free sensitization in MR-TADF OLEDs. The Innovation Materials 4:100210. https://doi.org/10.59717/j.xinn-mater.2026.100210

Xu L., Xiao S., Yang Y., et al. (2026). Weak emissive D-O-A organic phosphor: Exceptional matrix-free sensitization in MR-TADF OLEDs. The Innovation Materials 4:100210. https://doi.org/10.59717/j.xinn-mater.2026.100210

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Weak emissive D-O-A organic phosphor: Exceptional matrix-free sensitization in MR-TADF OLEDs

GRAPHICAL ABSTRACT

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