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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Ultralong MRTADF and Room‐Temperature Phosphorescence Enabled Color‐Tunable and High‐Temperature Dual‐Mode Organic Afterglow from Indolo[3,2‐b]carbazole

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(37)

Published: March 29, 2024

Abstract Organic afterglow can be generated from persistent thermally activated delayed fluorescence (pTADF) or organic ultralong room temperature phosphorescence (OURTP), but the pTADF plus OURTP type is challenging to achieve, especially for color‐tunable and high‐temperature ones. Herein, an accessible strategy toward such dual‐mode presented by doping indolo[3,2‐b]carbazole ( ICZ‐ p 1 ) into polymethyl methacrylate (PMMA). The resulting films exhibit photo‐activated with two emission peaks of ca . 435 497 nm. Impressively, their longest lifetimes respectively reach 2.28 2.47 s at 298 K, along 0.32 0.42 360 enabling high temperature. Experimental theoretical results reveal that associated elimination molecular O 2 inside film composed multi‐resonance (MR) effect OURTP. By altering 77 358 afterglows green blue are harvested ranges. Benefiting (MRTADF) characteristics, this emitter release narrow‐band electroluminescence. Consequently, obtained here may offer important references chasing MRTADF OURTP‐type showing features.

Language: Английский

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Fusion of Heterocyclic Aromatic Hydrocarbons With Multiple Resonance: Balancing Spectral Redshifts and Broadening

Advanced Optical Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 12, 2025

Abstract Efforts to fabricate ideal narrowband, long‐wavelength (>520 nm) multiple resonance (MR) emitters are often hampered by the mutual obstacles of effective spectral redshift and maintaining a small full width at half maximum (FWHM). This review focuses on sophisticated molecular design methodology called “fusing heterocyclic aromatic hydrocarbons (HAHs) with MR” overcome aforementioned challenges. Here, HAH serves as rigid structural fragment modest reorganization energy, which mainly plays role reducing ground‐excited state displacement redshift, while MR restricting low‐frequency vibrational coupling narrowband emission. The synergy these two advantages theoretically allows significant emission peak further narrowing spectrum. Utilizing ingeniously designed emitters, corresponding devices can achieve superior external quantum efficiencies over 20% remarkably FWHMs <25 nm in green red regions. These discoveries will spur development full‐color, high‐efficiency usher transformative shift organic light‐emitting diode industry.

Language: Английский

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Combining Carbazole Building Blocks and ν‐DABNA Heteroatom Alignment for a Double Boron‐Embedded MR‐TADF Emitter with Improved Performance

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(32)

Published: June 13, 2023

Building blocks and heteroatom alignments are two determining factors in designing multiple resonance (MR)-type thermally activated delayed fluorescence (TADF) emitters. Carbazole-fused MR emitters, represented by CzBN derivatives, the of ν-DABNA star series MR-TADF emitters that show impressive performances from aspects building alignments, respectively. Herein, a novel analog, Π-CzBN, featuring alignment is developed via facile one-shot lithium-free borylation. Π-CzBN exhibits superior photophysical properties with photoluminescence quantum yield close to 100 % narrowband sky blue emission full width at half maximum (FWHM) 16 nm/85 meV. It also gives efficient TADF small singlet-triplet energy offset 40 meV fast reverse intersystem crossing rate 2.9×105 s-1 . The optimized OLED using as emitter achieves an exceptional external efficiency 39.3 low roll-off 20 1000 cd m-2 495 nm FWHM 21 nm/106 meV, making it one best reported devices based on comprehensive performance.

Language: Английский

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Marching Toward Long‐Wavelength Narrowband Emissive Multi‐Resonance Delayed Fluorescence Emitters for Organic Light Emitting Diodes

Advanced Optical Materials, Journal Year: 2023, Volume and Issue: 11(22)

Published: Oct. 4, 2023

Abstract Over the past decade, thermally activated delayed fluorescence (TADF) emitters have garnered tremendous impetus because of their ability to harvest 100% excitons for light emission in organic emitting diodes (OLEDs). However, despite superior external quantum efficiencies (> 35%), broad spectra with associated full‐width‐at‐half maximum (FWHM > 70 nm) present a limiting factor that must be solved. Recently, multiple‐resonance TADF (MR‐TADF) materials based on heteroatom doped polyaromatic hydrocarbons gained astonishing attention owing remarkable narrowband < 30 nm). majority reported MR‐TADF falls blue/green region, which inevitably jeopardizes application full‐color OLEDs. Therefore, there is an urgent need develop new molecular designs expanding color‐gamut emitters, i.e., λ em 550 nm without compromising emission. To best current knowledge, no detailed reviews focusing different design strategies producing long‐wavelength been date. this end, review highlighting recent advances constructing presented, and photophysics OLED performance discussed. Finally, status future prospects are

Language: Английский

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High‐Efficiency Ultraviolet Electroluminescence from Multi‐Resonance Phosphine Oxide Polycyclic Aromatics

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(5)

Published: Dec. 7, 2023

Abstract Efficient ultraviolet (UV) electroluminescent materials remain a great challenge, since short peak wavelength <400 nm and narrow full width at half maximum (FWHM) <50 are simultaneously required. In this sense, multi‐resonance (MR) thermally activated delayed fluorescence (TADF) emitters featuring narrow‐band emissions hold the promise for UV applications. Herein, novel MR‐TADF skeleton carbazole‐phosphine oxide (P=O) fused aromatics is developed to construct first two MR named CzP2PO tBCzP2PO . addition synergistic resonance effects of P=O N atom, sp 3 ‐hybrid P atom renders curved polycyclic planes , giving rise their narrowband with wavelengths <390 FWHM<35 nm. Besides configuration quasi‐planarization radiation enhancement quenching suppression, moiety further enhances singlet‐triplet coupling facilitate reverse intersystem crossing, resulting in state‐of‐the‐art photoluminescence quantum yield 62 % doped films. As consequence, endowed its organic light‐emitting diodes 382 FWHM 32 nm, especially record‐high external efficiency (EQE) 15.1 among all kinds devices. Our results demonstrate potential based practical applications including optoelectronics, biology medicine science.

Language: Английский

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Secondary donor-acceptor group enable efficient pure green organic light-emitting devices based on multi-resonance TADF emitters

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 481, P. 148794 - 148794

Published: Jan. 14, 2024

Language: Английский

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Negatively Curved Octagon‐Incorporated Aza‐nanographene and its Assembly with Fullerenes

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(15)

Published: Feb. 12, 2024

Abstract A negatively curved aza‐nanographene (NG) containing two octagons was synthesized by a regioselective and stepwise cyclodehydrogenation procedure, in which double aza[7]helicene simultaneously formed as an intermediate. Their saddle‐shaped structures with negative curvature were unambiguously confirmed X‐ray crystallography, thereby enabling the exploration of structure–property relationship photophysical, electrochemical conformational studies. Moreover, assembly octagon‐embedded aza‐NG fullerenes probed fluorescence spectral titration, record‐high binding constants ( K =9.5×10 3 M −1 C 60 , =3.7×10 4 70 ) found among reported polycyclic aromatic compounds. The tight association further elucidated diffraction analysis their co‐crystal, showed formation 1 : complex substantial concave‐convex interactions.

Language: Английский

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Boron‐ and Oxygen‐Doped π‐Extended Helical Nanographene with Circularly Polarised Thermally Activated Delayed Fluorescence

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(19)

Published: Jan. 25, 2024

Abstract Helical nanographenes have garnered substantial attention owing to their finely adjustable optical and semiconducting properties. The strategic integration of both helicity heteroatoms into the nanographene structure, facilitated by a boron‐oxygen‐based multiple resonance (MR) thermally activated delayed fluorescence (TADF), elevates its photophysical chiroptical features. This signifies introduction an elegant category helical that combines (TADF) (CPL) In this direction, we report synthesis, optical, properties boron, oxygen‐doped Π‐extended nanographene. π‐extension induces distortion in DOBNA‐incorporated nanographene, endowing pair helicenes, ( P)‐ B2NG , M)‐ exhibiting circularly polarized luminescence with g lum −2.3×10 −3 +2.5×10 respectively. exhibited MR‐TADF lifetime below 5 μs, reasonably high quantum yield (50 %). Our molecular design enriches opens up new opportunities multidisciplinary fields.

Language: Английский

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Narrowband Fluorescent Emitters Based on BN‐Doped Polycyclic Aromatic Hydrocarbons for Efficient and Stable Organic Light‐Emitting Diodes

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(46)

Published: Sept. 30, 2023

Organic light-emitting diodes (OLEDs) using conventional fluorescent emitters are currently attracting considerable interests due to outstanding stability and abundant raw materials. To construct high-performance narrowband fluorophores satisfy requirements of ultra-high-definition displays, a strategy fusing multi-resonance BN-doped moieties naphthalene is proposed two novel fluorophores. Green Na-sBN red Na-dBN, manifest narrow full-width at half-maxima 31 nm, near-unity photoluminescence quantum yields molecular horizontal dipole ratios above 90 %. Their OLEDs exhibit the state-of-the-art performances including high external efficiencies (EQE), ultra-low efficiency roll-off long operational lifetimes. The Na-sBN-based device achieves EQE as 28.8 % remains 19.8 even luminance 100,000 cd m-2 , Na-dBN-based acquires record-high 25.2 among all pure emitters.

Language: Английский

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