Facilitating Intrinsic Delayed Fluorescence of Conjugated Emitters by Inter-Chromophore Interaction

Chemical Science, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Delayed fluorescence (DF) is a unique emitting phenomenon of great interest for important applications in organic optoelectronics. In general, DF requires well-separated frontier orbitals, inherently corresponding to charge transfer (CT)-type emitters. However, facilitating intrinsic local excited (LE)-type conjugated emitters remains very challenging. Aiming overcome this obstacle, we demonstrate new molecular design strategy with DF-inactive B,N-multiple resonance (MR) emitter as model system. Without the necessity doping heavy atoms, synthesized co-facial dimer which an excimer-like state (S

Language: Английский

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Boron‐Dipyrromethene Emitters with Strengthened Rigidity and Restricted Scissoring Vibration for High‐Performance OLEDs With Deep‐Red Narrowband Emission

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 17, 2024

Abstract Organic light‐emitting diodes (OLEDs) using a simple solution‐processing approach have natural advantages in cost‐effective commercialization. However, solution‐processed deep‐red OLEDs are rarely reported due to the scarcity of efficient purely organic narrowband red emitters with commendable film‐forming capabilities. Herein, strategy is proposed develop molecules emission by expanding rigid conjugated frame block rotation α position boron‐dipyrromethene (BODIPY) core restricted twisting vibration. Furtherly, introducing moderate donor meso‐position BODIPY core, bathochromic‐shifted can be achieved without sacrificing narrow full‐width at half‐maximum (FWHM) increasing electron density whole molecule and repulsive force distal units suppress stretching/scissoring By employing developed BODIPY‐derived materials as terminal thermally activated delayed fluorescence material assistant host fabricate OLED devices, maximum external quantum efficiency 16.43% an peak 672 nm FWHM 28 nm. This work, according knowledge, represents best instance based on typical fluorescent emitters.

Language: Английский

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Excited‐State Engineering of Chalcogen‐Bridged Chiral Molecules for Efficient OLEDs with Diverse Luminescence Mechanisms

Angewandte Chemie, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 23, 2024

Abstract The exploration of circularly polarized luminescence is important for advancing display and lighting technologies. Herein, by utilizing isomeric molecular engineering, a novel series chiral molecules are designed to exploit both thermally activated delayed fluorescence (TADF) room‐temperature phosphorescence (RTP) mechanisms efficient luminescence. cooperation small singlet‐triplet energy gap, moderate spin‐orbital coupling (SOC), large oscillator strength enables TADF emission, with photoluminescence quantum yields exceeding 90 %. By altering the symmetry structures, it demonstrated that intrinsic electronic SOC vibrational effects can be greatly enhanced facilitate RTP emission. Notably, through modulating simultaneous emissions, single‐molecule white emission successfully achieved. Accordingly, TADF‐based organic light‐emitting diode (OLED) achieves maximum external efficiency up 30 %, representing exceptional performance non‐aromatic amine‐based emitters. Furthermore, first OLED based on dual‐emissive material developed, establishing benchmark development advanced

Language: Английский

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Design of a Novel Selenium‐Containing Spiro Donor for Narrowband Blue Thermally Activated Delayed Fluorescence Emitters in OLEDs

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 26, 2024

Abstract Achieving high‐efficiency and narrowband deep‐blue emission is of great significance for organic light‐emitting diodes (OLEDs). Herein, a novel selenium‐containing spiro‐acridine donor, DspiroSe, designed constructing highly efficient blue emitters. The spiro structure DspiroSe contributes to suppressed aggregation‐caused quenching, while the selenium atom provides heavy‐atom effect. By attaching multiple resonance skeleton with different linkage strategies, two isomeric emitters sSeDDBN PsSe‐DABNA are obtained, which show promise as candidates OLEDs. Note that methods enable tuning spectrum from sky‐blue deep‐blue, demonstrating exceptional characterized by full‐width at half‐maximum 18 nm peak wavelength 445 in solution. Both exhibit high photoluminescence quantum yields exceeding 90% films, OLEDs using them achieve maximum external efficiencies (EQE max ) 26.5% 14.6%, respectively. utilizing TADF assistant host, EQE further increases 28.5% 19.1% PsSe‐DABNA. Notably, based excellent color purity Commission Internationale de l'Eclairage coordinates (0.145, 0.052), closely approaching BT.2020 standard.

Language: Английский

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Design and Performance of Sulfur and Selenium-substituted triarylboron D3-A TADF Emitters for OLED Applications

Organic Electronics, Journal Year: 2024, Volume and Issue: 134, P. 107130 - 107130

Published: Aug. 31, 2024

Language: Английский

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Rational design of narrowband deep blue MR-TADF dendrimers for high performance solution-processed all fluorescence white OLEDs

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: unknown, P. 155350 - 155350

Published: Sept. 1, 2024

Language: Английский

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Governing hybridized local and Charge-Transfer state in B,N-Embedded emitters for OLEDs

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: unknown, P. 158909 - 158909

Published: Dec. 1, 2024

Language: Английский

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Versatile benzthienocarbazole isomer derivatives as efficient TADF emitters and hosts for blue multi-resonance TADF emitters

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: unknown, P. 158958 - 158958

Published: Dec. 1, 2024

Language: Английский

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