Tetraborylated Multiple Resonance Emitter Incorporating B─O Bond-Embedded π-Extension for Ultra-Narrowband and
Yi-Cheng Zhao1, Yu-Tao Yang1, Shi-Peng Chen1
1Jiangsu Key Laboratory For Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, P. R. China.
Angewandte Chemie (International Ed. in English)
|July 9, 2026
Summary
Researchers developed a novel tetraboron compound for ultra-narrowband blue emission, achieving high efficiency and fast switching for advanced displays. This breakthrough promises energy-saving, ultra-high-definition visual technology.
Area of Science:
- Materials Science
- Organic Electronics
- Photophysics
Background:
- Ultra-narrowband multiple resonance (MR) thermally activated delayed fluorescence (MR-TADF) emitters are vital for advanced displays.
- Existing blue MR-TADF emitters struggle with narrow emission bandwidth, high quantum efficiency, and rapid reverse intersystem crossing (RISC).
Purpose of the Study:
- To design and develop novel MR-TADF emitters with improved performance for ultra-high-definition displays.
- To address the limitations of current blue MR-TADF emitters by enhancing emission characteristics and efficiency.
Main Methods:
- Introduction of a boron-oxygen (B─O) bond-embedded design strategy.
- Development of a 17-fused ring nanographene-based MR-TADF molecule (4B4N2O).
- Characterization of photophysical properties including emission spectra, photoluminescence quantum yield (PLQY), and RISC rate.
Main Results:
- The tetraboron compound 4B4N2O exhibits ultra-narrow blue emission (peak at 461 nm, FWHM of 11 nm).
- Achieved high PLQY (99%), high horizontal dipole ratio (93%), and a fast RISC rate (5.32 × 10^5 s^-1).
- The fabricated device demonstrated excellent external quantum efficiency (EQE) of 40.3% with minimal roll-off (EQE1000 = 31.4%), ultra-narrow EL FWHM (16 nm), and specific CIE coordinates (0.11, 0.18).
Conclusions:
- The novel boron-oxygen embedded tetraboron emitter significantly advances MR-TADF technology for displays.
- The developed emitter offers a promising solution for next-generation energy-saving ultra-high-definition displays and AR/VR applications.
Keywords:
bluemulti‐resonanceorganic light‐emitting diodesthermally activated delayed fluorescenceultra‐narrowbandMore Related Videos
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