Narrowband Emissive Thermally Activated Delayed Fluorescence Materials

Advanced Optical Materials, Journal Year: 2022, Volume and Issue: 10(22)

Published: Sept. 23, 2022

Abstract Organic thermally activated delayed fluorescence (TADF) materials have attracted significant research interest in the field of organic electronics because their inherent advantage 100% exciton utilization capability light‐emitting diodes (OLEDs) without use noble metals. However, despite high internal electroluminescence quantum efficiencies approaching unity, broad emission spectra with sizable full width at half maxima (FWHM; 60–100 nm) present a critical issue that must be solved for application ultrahigh‐definition OLED displays. Recently, new paradigm TADF featuring multiple resonance (MR) effect based on heteroatom‐doped polycyclic aromatic frameworks, referred to as MR‐TADF materials, has emerged and garnered considerable owing remarkable features efficient narrowband emissions extremely small FWHMs (≤30 nm). Currently, occupy prominent position cutting‐edge from both chemical physical perspectives. This review article focuses recent progress emissive systems perspective molecular design, photophysical properties, performance OLEDs. The current status future prospects this advanced material technology are discussed comprehensively.

Language: Английский

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Recent advances in the design of afterglow materials: mechanisms, structural regulation strategies and applications

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(22), P. 8005 - 8058

Published: Jan. 1, 2023

Afterglow materials have attracted widespread attention owing to their distinctive and long-lived optical emission properties which create exciting opportunities in various fields.

Language: Английский

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Organoboron-based multiple-resonance emitters: synthesis, structure–property correlations, and prospects

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(3), P. 1624 - 1692

Published: Jan. 1, 2024

This review highlights organoboron-based multiple-resonance compounds’ synthetic strategies classified as one-pot borylation, one-shot and late-stage functionalisation, explores material structure–photophysical property correlations.

Language: Английский

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Manipulating Exciton Dynamics toward Simultaneous High-Efficiency Narrowband Electroluminescence and Photon Upconversion by a Selenium-Incorporated Multiresonance Delayed Fluorescence Emitter

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(50), P. 22976 - 22984

Published: Dec. 7, 2022

Multiresonance thermal activated delayed fluorescence (MR-TADF) materials with an efficient spin-flip transition between singlet and triplet excited states remain demanding. Herein, we report MR-TADF compound (BN-Se) simultaneously possessing (reverse) intersystem crossing (ISC/RISC), fast radiative decay, close-to-unity quantum yield, narrowband emission by embedding a single selenium atom into common 4,4'-diazaborin framework. Benefitting from the high RISC efficiency accelerated heavy-atom effect, organic light-emitting diodes (OLEDs) based on BN-Se manifest excellent performance external of up to 32.6% ultralow roll-off 1.3% at 1000 cd m-2. Furthermore, ISC small inherent energy loss also render superior photosensitizer realize first example visible (λex > 450 nm)-to-UV (λem < 350 nm) triplet-triplet annihilation upconversion, (21.4%) extremely low threshold intensity (1.3 mW cm-2). This work not only aids in designing advanced pure molecules exciton dynamics but highlights value compounds beyond OLED applications.

Language: Английский

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Planar Chiral Multiple Resonance Thermally Activated Delayed Fluorescence Materials for Efficient Circularly Polarized Electroluminescence

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(6)

Published: Dec. 14, 2022

Chiral boron/nitrogen doped multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters are promising for highly efficient and color-pure circularly polarized organic light-emitting diodes (CP-OLEDs). Herein, we report two pairs of MR-TADF materials (Czp-tBuCzB, Czp-POAB) based on planar chiral paracyclophane with photoluminescence quantum yields up to 98 %. The enantiomers showed symmetric spectra dissymmetry factors |gPL | 1.6×10-3 in films. Meanwhile, the sky-blue CP-OLEDs (R/S)-Czp-tBuCzB an external efficiency 32.1 % narrowest full-width at half-maximum 24 nm among reported CP-OLEDs, while devices (R/S)-Czp-POAB displayed first nearly pure green CP electroluminescence |gEL 10-3 level. These results demonstrate incorporation chirality into emitter is a reliable strategy constructing CP-OLEDs.

Language: Английский

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Frontiers in Circularly Polarized Phosphorescent Materials

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(20)

Published: Feb. 20, 2023

Abstract Circularly polarized luminescence (CPL) materials have received increasing attention in recent years. Amongst various CPL materials, circularly phosphorescence (CPP) featuring long life‐time represent a novel research frontier and exhibit promising applications fields. Herein, the state‐of‐the‐art advances of CPP are systematically summarized, as classified into transition metal complexes, organic small molecules, polymers, organic/inorganic hybrid materials. Besides, light‐emitting diodes encryption display also summarized. Furthermore, current challenges future perspectives put forward. It is expected that this review will offer more inspirations for rational design advanced thus further promoting their practical applications.

Language: Английский

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Chiral materials and mechanisms for circularly polarized light-emitting diodes

Nature Photonics, Journal Year: 2024, Volume and Issue: 18(7), P. 658 - 668

Published: March 25, 2024

Language: Английский

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Liquid Crystals Doped with Chiral Fluorescent Polymer: Multi‐Color Circularly Polarized Fluorescence and Room‐Temperature Phosphorescence with High Dissymmetry Factor and Anti‐Counterfeiting Application

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(49)

Published: July 28, 2023

Chiral nematic liquid crystals (N*-LCs) can tremendously amplify circularly polarized luminescence (CPL) signals. Doped emissive N*-LCs have been substantially explored. However, their CPL performances still need to be improved, mainly due the unsatisfying helical twisting power (HTP) of commonly used chiral fluorescent dopants. polymers (CFHPs) outstanding optical activity and performance. The present contribution reports first success in constructing by doping CFHP into (5CB, N-LCs). assembly structures effectively signals CFHP. Owing high HTP CFHP, selective reflection band N*-LC adjusted fully cover its emission band. A nearly pure with a dissymmetry factor (glum ) up -1.87 is realized at 9 wt% concentration. Taking advantage mechanism, multi-color CPL-active glum are fabricated via further adding achiral fluorophores. Also noticeably, room-temperature phosphorescence -1.57 achieved. Anti-counterfeiting application demonstrated exploiting multi-mode characteristics created N*-LCs. established strategy for provides platform future exploring

Language: Английский

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Polymer‐Based Circularly Polarized Luminescent Materials

Advanced Optical Materials, Journal Year: 2023, Volume and Issue: 11(6)

Published: Jan. 19, 2023

Abstract Chiral materials capable of generating circularly polarized luminescence (CPL) have gained rapidly growing research interest by virtue their peculiar photophysical characteristics and far‐reaching applications. Amongst various CPL materials, polymer‐based constituted an important class owing to abundant types, ease manufacture, high thermal stability, as well as, tunable properties. The present work reviews the latest advances in constructing which are classified based on interaction modes between chiral luminescent components, that is, covalent interaction, non‐covalent without interactions. newly emerging categories nonconventional fluorescence‐based room temperature phosphorescence, with thermally activated delayed fluorescence properties also presented. Typical applications emitters organic light‐emitting diodes, information security encryption, optical sensors further discussed. Additionally, current challenges future perspectives this field summarized. This review article is expected stimulate more unprecedented achievements derived from thus promoting practical

Language: Английский

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Boron‐Based Narrowband Multiresonance Delayed Fluorescent Emitters for Organic Light‐Emitting Diodes

Advanced Photonics Research, Journal Year: 2022, Volume and Issue: 3(11)

Published: Sept. 4, 2022

Recently, the exploration of boron (B)/heteroatom‐embedded polycyclic nanographites featuring multiresonance thermally activated delayed fluorescence (MR‐TADF) garners astonishing attention to promote advancement organic light‐emitting diodes (OLEDs). Contrary traditional donor–acceptor (D–A)‐type TADF emitters, MR‐TADF emitters manifest narrowband emission with full width at half maximum (FWHM ≤ 40 nm) and superior photoluminescence quantum yield (PLQY) coupled small singlet–triplet energy splitting, which appeal their potential as promising candidates in fabricating efficient OLEDs. Growingly, deliver benchmark device performance comparable conventional TADF/phosphorescent emitters. However, they are suffering from major drawbacks such difficult realize full‐color slow exciton upconversion dynamics, aggregation‐caused quenching, severe efficiency roll‐off, poor operational lifetime, jeopardizes practical applicability. Herein, a comprehensive review on B‐based reported till date is presented, focusing different design strategies documented for circumventing aforementioned shortcomings. This divided into several subgroups based color materials draw electronics community toward constructing MR‐OLEDs. Finally, challenges opportunities discussed.

Language: Английский

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