1
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Zhong R, Wang M, Wang X, Wang S, Shao S, Wang L. 10-Dibenzothiophenyl-9,9-diphenylacridane-based multiple resonance emitters for high-efficiency narrowband green OLEDs with CIE y > 0.7 at high doping concentrations. Chem Sci 2024; 15:13290-13298. [PMID: 39183913 PMCID: PMC11340009 DOI: 10.1039/d4sc03705g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2024] [Accepted: 07/12/2024] [Indexed: 08/27/2024] Open
Abstract
Multiple resonance emitters are attractive for high-color-purity organic light-emitting diodes (OLEDs) because of their unique narrowband emissions; however, they are typically used at low doping concentrations (≤15 wt%) due to aggregation-caused quenching and spectral broadening induced by planar molecular skeletons. Here, we report two multiple resonance emitters (BThPAc-1 and BThPAc-2) consisting of a 10-dibenzothiophenyl-9,9-diphenylacridane segment for efficient narrowband green emission at high doping concentrations. The dibenzothiophenyl-9,9-diphenylacridane segment contains two carbon-bridged phenyl rings as steric groups to inhibit intermolecular aggregation and a dibenzothiophene unit to extend conjugation and red-shift the emission to the green region. The resultant emitters exhibit narrowband emissions that peaked at 509-510 nm with a full width at half-maximum (FWHM) of 32 nm in 1 wt% doping films, which are maintained at less than 35 nm even in neat films. Remarkably, OLEDs employing the emitters reveal pure-green electroluminescence with a maximum external quantum efficiency of 20.3% and CIE coordinates of (0.18, 0.72) at 30 wt% doping concentration, which represents the best color coordinates for green multiple resonance OLEDs at high doping concentrations.
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Affiliation(s)
- Rui Zhong
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 China
- School of Applied Chemistry and Engineering, University of Science and Technology of China Hefei Anhui 230026 China
| | - Mengyu Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 China
- School of Applied Chemistry and Engineering, University of Science and Technology of China Hefei Anhui 230026 China
| | - Xingdong Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 China
| | - Shumeng Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 China
| | - Shiyang Shao
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 China
- State Key Laboratory of Marine Resource Utilization in South China Sea, School of Materials Science and Engineering, Hainan University Haikou Hainan 570228 China
| | - Lixiang Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 China
- School of Applied Chemistry and Engineering, University of Science and Technology of China Hefei Anhui 230026 China
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2
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Feng Y, Xu Y, Qu C, Wang Q, Ye K, Liu Y, Wang Y. Structurally Tunable Donor-Bridge-Fluorophore Architecture Enables Highly Efficient and Concentration-Independent Narrowband Electroluminescence. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2403061. [PMID: 38782371 DOI: 10.1002/adma.202403061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 05/05/2024] [Indexed: 05/25/2024]
Abstract
Luminescent materials with narrowband emission have extraordinary significance for developing ultrahigh-definition display. B-N-containing multiple resonance thermally activated delayed fluorescence (MR-TADF) materials are strong contenders. However, their device performances pervasively encounter detrimental aggregation-caused quenching effect that is highly vulnerable to doping concentration, complicating device fabrication. Therefore, constructing highly efficient and concentration-independent MR-TADF emitters is of pragmatic importance for improving device controllability and reproducibility, simplifying manufacturing procedures, and conserving production costs. Here, by systematic arrangement of donor triphenylamine and fluorophore BNCz on distinct bridges, a spatial confinement strategy has been developed with a donor-bridge-fluorophore architecture. Structurally fine modulation and progressive evolution to construct molecular entities with congested steric hindrance effect that can suppress intermolecular interactions without substantially affecting the luminescence tone of fluorophore BNCz, resulting in highly efficient and concentration-independent narrowband emitters; through isomer engineering, two isomers BN-PCz-TPA and TPA-PCz-BN with different crystal stacking patterns are synthesized by altering the connection mode between triphenylamine and BNCz. As a result, BN-PCz-TPA-based device showcases maximum external quantum efficiency (EQE) of 36.3% with narrow full-width at half-maximum of 27 nm at 10 wt% doping concentration. Even at 20 wt% doping concentration, the maximum EQE remains at 32.5% and the emission spectrum is almost unchanged.
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Affiliation(s)
- Yu Feng
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Yincai Xu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Cheng Qu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Qingyang Wang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Kaiqi Ye
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Yu Liu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Yue Wang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
- Jihua Laboratory, 28 Huandao South Road, Foshan, Guangdong Province, 528200, P. R. China
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3
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Li MY, Wu H, Fan XC, Huang F, Yu J, Wang K, Zhang XH. Expanding Multiple-Resonance Structure of a Double-Borylated Skeleton by Fusing with Indolocarbazole a Multiple-Resonance Donor for Narrowband Green Emission. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2312098. [PMID: 38461523 DOI: 10.1002/smll.202312098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Revised: 03/01/2024] [Indexed: 03/12/2024]
Abstract
Double-borylated multiple-resonance (MR) skeletons are promising templates for high performance, while the chemical design space is relatively limited. Peripheral segments are often used to decorate/fuse MR skeletons and modulate the photophysics but they can also cause unwanted spectral broadening. Herein, a narrowband MR emitter ICzDBA by fusing an MR-featured donor segment indolocarbazole into a double-borylated MR skeleton is developed. In ICzDBA, the nitrogen atom located away from the core benzene ring can also contribute to the generation of the overall MR-featured distribution through the long-range conjugation effect, along with the other boron/nitrogen atoms on the phenyl center. Thus, ICzDBA in toluene displays a narrowband emission peaking at 507 nm with a full width at half maximum of merely 20 nm (0.09 eV). Moreover, organic light-emitting diode devices using ICzDBA emitter exhibit ultrapure green emission with Commission Internationale de l'Eclairage (CIE) coordinates of (0.27, 0.70) and a high external quantum efficiency of 32.5%. These results manifest the importance of MR characters of peripheral decorations/fusions in preserving the narrowband features of MR skeletons, which provides a solution for further expanding MR structures with well-maintained narrowband characters.
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Affiliation(s)
- Mo-Yuan Li
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Hao Wu
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Xiao-Chun Fan
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Feng Huang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Jia Yu
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Kai Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Xiao-Hong Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
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4
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Kondo Y, Tsutsui Y, Matsuo Y, Tanaka T, Seki S. Impacts of heteroatom substitution on the excited state dynamics of π-extended helicenes. NANOSCALE ADVANCES 2024:d4na00516c. [PMID: 39144158 PMCID: PMC11320297 DOI: 10.1039/d4na00516c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2024] [Accepted: 07/29/2024] [Indexed: 08/16/2024]
Abstract
Benzo-annulated aza[9]helicene ([9]AH) and thia[9]helicene ([9]TH) were prepared as novel π-extended heterohelicenes. [9]TH showed a quite short fluorescence lifetime of ∼0.3 ns and intense phosphorescence at low temperature that were attributed to its larger spin-orbit coupling and faster intersystem crossing between pseudo-degenerate S1/2 and triplet states.
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Affiliation(s)
- Yuto Kondo
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Nishikyo-ku Kyoto 615-8510 Japan
| | - Yusuke Tsutsui
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Nishikyo-ku Kyoto 615-8510 Japan
- JST-PRESTO Honcho 4-1-8, Kawaguchi Saitama 332-0012 Japan
| | - Yusuke Matsuo
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Nishikyo-ku Kyoto 615-8510 Japan
| | - Takayuki Tanaka
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Nishikyo-ku Kyoto 615-8510 Japan
| | - Shu Seki
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University Nishikyo-ku Kyoto 615-8510 Japan
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5
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Chen X, Sun L, Sukhanov AA, Doria S, Bussotti L, Zhao J, Xu H, Dick B, Voronkova VK, Di Donato M. Photophysics and photochemistry of thermally activated delayed fluorescence emitters based on the multiple resonance effect: transient optical and electron paramagnetic resonance studies. Chem Sci 2024; 15:10867-10881. [PMID: 39027280 PMCID: PMC11253189 DOI: 10.1039/d4sc02513j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Accepted: 05/31/2024] [Indexed: 07/20/2024] Open
Abstract
The photochemistry of two representative thermally activated delayed fluorescence (TADF) emitters based on the multiple resonance effect (MRE) (DABNA-1 and DtBuCzB) was studied. No significant TADF was observed in fluid solution, although the compounds have a long-lived triplet state (ca. 30 μs). We found that these planar boron molecules bind with Lewis bases, e.g., 4-dimethylaminopyridine (DMAP) or an N-heterocyclic carbene (NHC). A new blue-shifted absorption band centered at 368 nm was observed for DtBuCzB upon formation of the adduct; however, the fluorescence of the adduct is the same as that of the free DtBuCzB. We propose that photo-dissociation occurs for the DtBuCzB-DMAP adduct, which is confirmed by femtosecond transient absorption spectra, implying that fluorescence originates from DtBuCzB produced by photo-dissociation; the subsequent in situ re-binding was observed with nanosecdon transient absorption spectroscopy. No photo-dissociation was observed for the NHC adduct. Time-resolved electron paramagnetic resonance (TREPR) spectra show that the triplet states of DABNA-1 and DtBuCzB have similar zero field splitting (ZFS) parameters (D = 1450 MHz). Theoretical studies show that the slow ISC is due to small SOC and weak Herzberg-Teller coupling, although the S1/T1 energy gap is small (0.14 eV), which rationalizes the lack of TADF.
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Affiliation(s)
- Xi Chen
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology Dalian 116024 P. R. China
| | - Lei Sun
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Key Laboratory of Forestry Genetics & Biotechnology of Ministry of Education, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, College of Chemical Engineering, Nanjing Forestry University Nanjing 210037 P. R. China
- School of Chemistry and Chemical Engineering, Henan Normal University Xinxiang 453002 China
| | - Andrey A Sukhanov
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS Kazan 420029 Russia
| | - Sandra Doria
- LENS (European Laboratory for Non-Linear Spectroscopy) Via N. Carrara 1 50019 Sesto Fiorentino (FI) Italy
- ICCOM-CNR Via Madonna del Piano 10-12 50019 Sesto Fiorentino (FI) Italy
| | - Laura Bussotti
- LENS (European Laboratory for Non-Linear Spectroscopy) Via N. Carrara 1 50019 Sesto Fiorentino (FI) Italy
| | - Jianzhang Zhao
- State Key Laboratory of Fine Chemicals, Frontier Science Center for Smart Materials, School of Chemical Engineering, Dalian University of Technology Dalian 116024 P. R. China
| | - Haijun Xu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Key Laboratory of Forestry Genetics & Biotechnology of Ministry of Education, Jiangsu Provincial Key Lab for the Chemistry and Utilization of Agro-Forest Biomass, College of Chemical Engineering, Nanjing Forestry University Nanjing 210037 P. R. China
- School of Chemistry and Chemical Engineering, Henan Normal University Xinxiang 453002 China
| | - Bernhard Dick
- Lehrstuhl für Physikalische Chemie, Institut für Physikalische und Theoretische Chemie, Universität Regensburg Regensburg 93053 Germany
| | - Violeta K Voronkova
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS Kazan 420029 Russia
| | - Mariangela Di Donato
- LENS (European Laboratory for Non-Linear Spectroscopy) Via N. Carrara 1 50019 Sesto Fiorentino (FI) Italy
- ICCOM-CNR Via Madonna del Piano 10-12 50019 Sesto Fiorentino (FI) Italy
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6
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Chen YK, Lei J, Wu TL. Elevating the upconversion performance of a multiple resonance thermally activated delayed fluorescence emitter via an embedded azepine approach. Chem Sci 2024; 15:10146-10154. [PMID: 38966359 PMCID: PMC11220617 DOI: 10.1039/d4sc02351j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Accepted: 05/22/2024] [Indexed: 07/06/2024] Open
Abstract
Multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters hold promise for efficient organic light-emitting diodes (OLEDs) and wide gamut displays. An azepine donor is introduced into the boron-nitrogen system for the first time. The highly twisted conformation of a seven-ring embedded new molecule, TAzBN, increases the intermolecular distances, suppressing self-aggregation emission quenching. Meanwhile, the azepine donor is crucial to achieve a narrow singlet-triplet gap (0.03 eV) as well as boost the reverse intersystem crossing (RISC) rate to 8.50 × 105 s-1. It is noteworthy that TAzBN demonstrates an impressive photoluminescence quantum yield of 94%. In addition, its nonsensitized OLED displayed a remarkable external quantum efficiency (EQEmax) with values peaking at 27.3%, and an EQE of 21.4% at 500 cd m-2. This finding shows that when TAzBN is used at a high concentration of 10 wt%, its device maintains efficiency even at higher brightness levels, highlighting TAzBN's resistance to aggregation quenching. Furthermore, TAzBN enantiomers showed circularly polarized photoluminescence characteristics with dissymmetry factors |g PL| of up to 1.07 × 10-3 in doped films. The curved heptagonal geometry opens an avenue to design the MR-TADF emitters with fast spin-flip and chiroptical properties.
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Affiliation(s)
- Yi-Kuan Chen
- Department of Chemistry, National Tsing Hua University No. 101, Sec. 2, Kuang-Fu Rd. Hsinchu 300044 Taiwan
| | - Jian Lei
- Department of Chemistry, National Tsing Hua University No. 101, Sec. 2, Kuang-Fu Rd. Hsinchu 300044 Taiwan
- Institute of Atomic and Molecular Sciences, Academia Sinica No. 1, Sec. 4, Roosevelt Rd. Taipei 106319 Taiwan
| | - Tien-Lin Wu
- Department of Chemistry, National Tsing Hua University No. 101, Sec. 2, Kuang-Fu Rd. Hsinchu 300044 Taiwan
- College of Semiconductor Research No. 101, Sec. 2, Kuang-Fu Rd. Hsinchu 300044 Taiwan
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7
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Mamada M, Aoyama A, Uchida R, Ochi J, Oda S, Kondo Y, Kondo M, Hatakeyama T. Efficient Deep-Blue Multiple-Resonance Emitters Based on Azepine-Decorated ν-DABNA for CIE y below 0.06. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2402905. [PMID: 38695744 DOI: 10.1002/adma.202402905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 04/19/2024] [Indexed: 05/23/2024]
Abstract
Ultrapure deep-blue emitters are in high demand for organic light-emitting diodes (OLEDs). Although color coordinates serve as straightforward parameters for assessing color purity, precise control over the maximum wavelength and full-width at half-maximum is necessary to optimize OLED performance, including luminance efficiency and luminous efficacy. Multiple-resonance (MR) emitters are promising candidates for achieving ideal luminescence properties; consequently, a wide variety of MR frameworks have been developed. However, most of these emitters experience a wavelength displacement from the ideal color, which limits their practical applicability. Therefore, a molecular design that is compatible with MR emitters for modulating their energy levels and color output is particularly valuable. Here, it is demonstrated that the azepine donor unit induces an appropriate blue-shift in the emission maximum while maintaining efficient MR characteristics, including high photoluminescence quantum yield, narrow emission, and a fast reverse intersystem crossing rate. OLEDs using newly developed MR emitters based on the ν-DABNA framework simultaneously exhibit a high quantum efficiency of ≈30%, luminous efficacy of ≈20 lm W-1, exceptional color purity with Commission Internationale de l'Éclairage coordinates as low as (0.14, 0.06), and notably high operational stability. These results demonstrate unprecedentedly high levels compared with those observed in previously reported deep-blue emitters.
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Affiliation(s)
- Masashi Mamada
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Akio Aoyama
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
| | - Ryota Uchida
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Junki Ochi
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Susumu Oda
- Department of Applied Chemistry, Graduate School of Science and Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama, 350-8585, Japan
| | - Yasuhiro Kondo
- SK JNC Japan Co., Ltd., 5-1 Goi Kaigan, Ichihara, Chiba, 290-8551, Japan
| | - Masakazu Kondo
- JNC Co., Ltd., 5-1 Goi Kaigan, Ichihara, Chiba, 290-8551, Japan
| | - Takuji Hatakeyama
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
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8
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Chen JF, Gao QX, Yao H, Shi B, Zhang YM, Wei TB, Lin Q. Recent advances in circularly polarized luminescence of planar chiral organic compounds. Chem Commun (Camb) 2024; 60:6728-6740. [PMID: 38884278 DOI: 10.1039/d4cc01698j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2024]
Abstract
Circularly polarized luminescence (CPL), as an important chiroptical phenomenon, can not only directly characterize excited-state structural information about chiroptical materials but also has great application prospects in 3D optical displays, information storage, biological probes, CPL lasers and so forth. Recently, chiral organic small molecules with CPL have attracted a lot of research interest because of their excellent luminescence efficiency, clear molecular structures, unique flexibility and easy functionalization. Planar chiral organic compounds make up an important class of chiral organic small molecular materials and often have rigid macrocyclic skeletons, which have important research value in the field of chiral supramolecular chemistry (e.g., chiral self-assembly and chiral host-guest chemistry). Therefore, research into planar chiral organic compounds has become a hotspot for CPL. It is time to summarize the recent developments in CPL-active compounds based on planar chirality. In this feature article, we summarize various types of CPL-active compounds based on planar chirality. Meanwhile, we overview recent research in the field of planar chiral CPL-active compounds in terms of optoelectronic devices, asymmetric catalysis, and chiroptical sensing. Finally, we discuss their future research prospects in the field of CPL-active materials. We hope that this review will be helpful to research work related to planar chiral luminescent materials and promote the development of chiral macrocyclic chemistry.
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Affiliation(s)
- Jin-Fa Chen
- Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. China.
| | - Qing-Xiu Gao
- Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. China.
| | - Hong Yao
- Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. China.
| | - Bingbing Shi
- Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. China.
| | - You-Ming Zhang
- Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. China.
| | - Tai-Bao Wei
- Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. China.
| | - Qi Lin
- Key Laboratory of Eco-Environment-Related Polymer Materials, Ministry of Education of China, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, P. R. China.
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9
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Matsuo Y, Gon M, Tanaka K, Seki S, Tanaka T. Synthesis of Aza[ n]helicenes up to n = 19: Hydrogen-Bond-Assisted Solubility and Benzannulation Strategy. J Am Chem Soc 2024; 146:17428-17437. [PMID: 38866732 DOI: 10.1021/jacs.4c05156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2024]
Abstract
Synthetic challenges toward anomalous structures and electronic states often involve handling problems such as insolubility in common organic solvents and oxidative degradation under aerobic conditions. We designed benzo-annulated aza[n]helicenes, which benefit from both the suppressed elevation of highest occupied molecular orbital (HOMO) energies and high solubility due to hydrogen bonding with solvent molecules to overcome these challenges. This strategy enabled the synthesis of six new aza[n]helicenes ([n]AHs) of different lengths (n = 9-19) from acyclic precursors via one-pot intramolecular oxidative fusion reactions. The structures of all of the synthesized aza[n]helicenes were determined by X-ray diffraction (XRD) analysis, and their electrochemical potentials were measured by cyclic voltammetry. Among the synthesized aza[n]helicenes, [17]AH and [19]AH are the first heterohelicenes with a triple-layered helix. The noncovalent interaction (NCI) plots confirm the existence of an effective π-π interaction between the layers. The absorption and fluorescence spectra red-shifted as the helical lengths increased, without any distinct saturation points. The optical resolutions of N-butylated [9]AH, [11]AH, [13]AH, and [15]AH were accomplished, and their circular dichroism (CD) and circularly polarized luminescence (CPL) were measured. Thus, the structural, (chir)optical, and electrochemical properties of the aza[n]helicenes were comprehensively analyzed.
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Affiliation(s)
- Yusuke Matsuo
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Masayuki Gon
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Kazuo Tanaka
- Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Shu Seki
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Takayuki Tanaka
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
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10
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Hirano J, Miyoshi S, Yashima E, Ikai T, Shinokubo H, Fukui N. Synthesis of sterically congested double helicene by alkyne cycloisomerization. Chem Commun (Camb) 2024; 60:6035-6038. [PMID: 38775051 DOI: 10.1039/d4cc01573h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Abstract
Alkyne cycloisomerization of 2,7,10,15-tetra(ortho-alkynylphenyl)benzo[g,p]chrysene containing bulky 4-alkoxy-2,6-dimethylphenyl groups at the alkyne terminals selectively proceeded at the sterically crowded bay-region. The obtained double helicene adopts a distorted structure with a high racemization barrier due to the intramolecular steric repulsion.
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Affiliation(s)
- Junichiro Hirano
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
| | - Sayaka Miyoshi
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
| | - Eiji Yashima
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
| | - Tomoyuki Ikai
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
- PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan
| | - Hiroshi Shinokubo
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
- Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Norihito Fukui
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan.
- PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan
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11
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Zender E, Valverde D, Neubaur R, Karger S, Virovets A, Bolte M, Lerner HW, Olivier Y, Wagner M. Borylation and rearrangement reactions of azasilaanthracenes to afford B,N-doped nanographenes. Dalton Trans 2024; 53:9294-9300. [PMID: 38747255 DOI: 10.1039/d4dt01166j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
An air-stable B3,N3-containing dibenzobisanthene (8) was prepared in 29% yield by heating a 1,3,5-tri(azasilaanthryl)benzene (5) with BBr3 (180 °C). Under these conditions, the reaction does not stop after threefold SiMe2/BBr exchange but proceeds further via two rearrangement and two intramolecular C-H borylation steps. Some mechanistic details were unveiled by using smaller model systems and applying lower reaction temperatures. According to X-ray crystallography, compound 8 has a helically distorted scaffold. Due to its multiple resonance structure, it shows a narrow-band blue-green emission (λem = 493 nm; ΦPL = 84%; FWHM = 0.20 eV; THF); samples measured in PMMA gave prompt and delayed fluorescence lifetimes of 10.7 ns and 136 μs, respectively. The optical properties of 8 and of structurally related species were also investigated by quantum-chemical means: most of these compounds exhibit a small energy gap ΔEST between the lowest excited singlet (S1) and triplet (T1) states and a non-negligible spin-orbit coupling (SOC) between S1 and T1/T2, demonstrating their potential as thermally activated delayed fluorescence (TADF) emitters.
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Affiliation(s)
- Elena Zender
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany.
| | - Danillo Valverde
- Laboratory for Computational Modeling of Functional Materials, Namur Institute of Structured Matter, University of Namur, Rue de Bruxelles, 61, 5000 Namur, Belgium.
| | - Robert Neubaur
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany.
| | - Sebastian Karger
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany.
| | - Alexander Virovets
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany.
| | - Michael Bolte
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany.
| | - Hans-Wolfram Lerner
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany.
| | - Yoann Olivier
- Laboratory for Computational Modeling of Functional Materials, Namur Institute of Structured Matter, University of Namur, Rue de Bruxelles, 61, 5000 Namur, Belgium.
| | - Matthias Wagner
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany.
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12
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Ni F, Huang Y, Qiu L, Yang C. Synthetic progress of organic thermally activated delayed fluorescence emitters via C-H activation and functionalization. Chem Soc Rev 2024; 53:5904-5955. [PMID: 38717257 DOI: 10.1039/d3cs00871a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
Thermally activated delayed fluorescence (TADF) emitters have become increasingly prominent due to their promising applications across various fields, prompting a continuous demand for developing reliable synthetic methods to access them. This review aims to highlight the progress made in the last decade in synthesizing organic TADF compounds through C-H bond activation and functionalization. The review begins with a brief introduction to the basic features and design principles of TADF emitters. It then provides an overview of the advantages and concise development of C-H bond transformations in constructing TADF emitters. Subsequently, it summarizes both transition-metal-catalyzed and non-transition-metal-promoted C-H bond transformations used for the synthesis of TADF emitters. Finally, the review gives an outlook on further challenges and potential directions in this field.
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Affiliation(s)
- Fan Ni
- National Engineering Lab of Special Display Technology, State Key Lab of Advanced Display Technology, Academy of Opto-Electronic Technology, Intelligent Interconnected Systems Laboratory of Anhui, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronic Engineering, Hefei University of Technology, Hefei, Anhui 230009, P. R. China.
| | - Yipan Huang
- National Engineering Lab of Special Display Technology, State Key Lab of Advanced Display Technology, Academy of Opto-Electronic Technology, Intelligent Interconnected Systems Laboratory of Anhui, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronic Engineering, Hefei University of Technology, Hefei, Anhui 230009, P. R. China.
| | - Longzhen Qiu
- National Engineering Lab of Special Display Technology, State Key Lab of Advanced Display Technology, Academy of Opto-Electronic Technology, Intelligent Interconnected Systems Laboratory of Anhui, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronic Engineering, Hefei University of Technology, Hefei, Anhui 230009, P. R. China.
| | - Chuluo Yang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, Guangdong 518060, P. R. China.
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13
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Shizu K, Kaji H. Quantitative prediction of rate constants and its application to organic emitters. Nat Commun 2024; 15:4723. [PMID: 38830867 PMCID: PMC11148104 DOI: 10.1038/s41467-024-49069-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 05/23/2024] [Indexed: 06/05/2024] Open
Abstract
Many phenomena in nature consist of multiple elementary processes. If we can predict all the rate constants of respective processes quantitatively, we can comprehensively predict and understand various phenomena. Here, we report that it is possible to quantitatively predict all related rate constants and quantum yields without conducting experiments, using multiple-resonance thermally activated delayed fluorescence (MR-TADF) as an example. MR-TADFs are excellent emitters because of its narrow emission, high luminescence efficiency, and chemical stability, but they have one drawback: slow reverse intersystem crossing (RISC), leading to efficiency roll-off and reduced device lifetime. Here, we show a quantum chemical calculation method for quantitatively obtaining all the rate constants and quantum yields. This study reveals a strategy to improve RISC without compromising other important factors: radiative decay rate constants, photoluminescence quantum yields, and emission linewidths. Our method can be applied in a wide range of research fields, providing comprehensive understanding of the mechanism including the time evolution of excitons.
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Affiliation(s)
- Katsuyuki Shizu
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, 611-0011, Japan
| | - Hironori Kaji
- Institute for Chemical Research, Kyoto University, Uji, Kyoto, 611-0011, Japan.
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14
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Weerasinghe RW, Madayanad Suresh S, Hall D, Matulaitis T, Slawin AMZ, Warriner S, Lee YT, Chan CY, Tsuchiya Y, Zysman-Colman E, Adachi C. A Boron, Nitrogen, and Oxygen Doped π-Extended Helical Pure Blue Multiresonant Thermally Activated Delayed Fluorescent Emitter for Organic Light Emitting Diodes That Shows Fast k RISC Without the Use of Heavy Atoms. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2402289. [PMID: 38581139 DOI: 10.1002/adma.202402289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 04/03/2024] [Indexed: 04/08/2024]
Abstract
Narrowband emissive multiresonant thermally activated delayed fluorescence (MR-TADF) emitters are a promising solution to achieve the current industry-targeted color standard, Rec. BT.2020-2, for blue color without using optical filters, aiming for high-efficiency organic light-emitting diodes (OLEDs). However, their long triplet lifetimes, largely affected by their slow reverse intersystem crossing rates, adversely affect device stability. In this study, a helical MR-TADF emitter (f-DOABNA) is designed and synthesized. Owing to its π-delocalized structure, f-DOABNA possesses a small singlet-triplet gap, ΔEST, and displays simultaneously an exceptionally faster reverse intersystem crossing rate constant, kRISC, of up to 2 × 106 s-1 and a very high photoluminescence quantum yield, ΦPL, of over 90% in both solution and doped films. The OLED with f-DOABNA as the emitter achieved a narrow deep-blue emission at 445 nm (full width at half-maximum of 24 nm) associated with Commission Internationale de l'Éclairage (CIE) coordinates of (0.150, 0.041), and showed a high maximum external quantum efficiency, EQEmax, of ≈20%.
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Affiliation(s)
- Rangani Wathsala Weerasinghe
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Motooka, Nishi, Fukuoka, 819-0395, Japan
| | - Subeesh Madayanad Suresh
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - David Hall
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - Tomas Matulaitis
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - Alexandra M Z Slawin
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - Stuart Warriner
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Yi-Ting Lee
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Motooka, Nishi, Fukuoka, 819-0395, Japan
| | - Chin-Yiu Chan
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, 000-000, China
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, 000-000, China
| | - Youichi Tsuchiya
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Motooka, Nishi, Fukuoka, 819-0395, Japan
| | - Eli Zysman-Colman
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - Chihaya Adachi
- Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Motooka, Nishi, Fukuoka, 819-0395, Japan
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15
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Kang S, Kim T. Comparative study of TDDFT and TDDFT-based STEOM-DLPNO-CCSD calculations for predicting the excited-state properties of MR-TADF. Heliyon 2024; 10:e30926. [PMID: 38779014 PMCID: PMC11109791 DOI: 10.1016/j.heliyon.2024.e30926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/07/2024] [Accepted: 05/08/2024] [Indexed: 05/25/2024] Open
Abstract
The time dependent density functional theory (TDDFT) and TDDFT/similarity transformed EOM domain-based local pair natural orbital CCSD (STEOM-DLPNO-CCSD) calculations were explored to estimate their validity in predicting the excited-state properties of multi-resonant thermally activated delayed fluorescence (MR-TADF) materials. Obviously, it was demonstrated that TDDFT calculation is inadequate to provide the quantitative prediction of the lowest singlet excited-state (S1), the lowest triplet excited-state (T1), and ΔEST. On the other hand, TDDFT/STEOM-DNLPNO-CCSD calculation reveals the superior prediction of S1, T1, and ΔEST that are in quantitative agreement with experiments. More importantly, it was found that TD-LC-⎤ * HPBE/STEOM-DLPNO-CCSD calculation provides the most accurate prediction of S1, T1, and ΔEST. Accordingly, we suggest that TD-LC-⎤ * HPBE/STEOM-DLPNO-CCSD calculation should be utilized to compute the excited-states properties of MR-TADF materials accurately.
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Affiliation(s)
- Sunwoo Kang
- Department of Chemistry, Dankook University, Cheonan, Chungnam, 31116, South Korea
| | - Taekyung Kim
- Department of Materials Science and Engineering, Hongik University, Sejongsi, 30016, South Korea
- Department of Information Display Engineering, Hongik University, Seoul, 04066, South Korea
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16
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Wu L, Huang Z, Miao J, Wang S, Li X, Li N, Cao X, Yang C. Orienting Group Directed Cascade Borylation for Efficient One-Shot Synthesis of 1,4-BN-Doped Polycyclic Aromatic Hydrocarbons as Narrowband Organic Emitters. Angew Chem Int Ed Engl 2024; 63:e202402020. [PMID: 38385590 DOI: 10.1002/anie.202402020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 02/21/2024] [Accepted: 02/21/2024] [Indexed: 02/23/2024]
Abstract
1,4-BN-doped polycyclic aromatic hydrocarbons (PAHs) have emerged as very promising emitters in organic light-emitting diodes (OLEDs) due to their narrowband emission spectra that may find application in high-definition displays. While considerable research has focused on investigating the properties of these materials, less attention has been placed on their synthetic methodology. Here we developed an efficient synthetic method for 1,4-BN-doped PAHs, which enables sustainable production of narrowband organic emitting materials. By strategically introducing substituents, such as methyl, tert-butyl, phenyl, and chloride, at the C5 position of the 1,3-benzenediamine substrates, we achieved remarkable regioselective borylation in the para-position of the substituted moiety. This approach facilitated the synthesis of a diverse range of 1,4-BN-doped PAHs emitters with good yields and exceptional regioselectivity. The synthetic method demonstrated excellent scalability for large-scale production and enabled late-stage transformation of the borylated products. Mechanistic investigations provided valuable insights into the pivotal roles of electron effect and steric hindrance effect in achieving highly efficient regioselective borylation. Moreover, the outstanding device performance of the synthesized compounds 10 b and 6 z, underscores the practicality and significance of the developed method.
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Affiliation(s)
- Lin Wu
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
- College of Physical and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Zhongyan Huang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Jingsheng Miao
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Shuni Wang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Xinyao Li
- Department of Chemistry, College of Sciences, Shanghai University, Shanghai, 200444, P. R. of China
| | - Nengquan Li
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Xiaosong Cao
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
| | - Chuluo Yang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, P. R. China
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17
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Situ Z, Li X, Gao H, Zhang J, Li Y, Zhao F, Kong J, Zhao H, Zhou M, Wang Y, Kuang Z, Xia A. Accelerating Intersystem Crossing in Multiresonance Thermally Activated Delayed Fluorescence Emitters via Long-Range Charge Transfer. J Phys Chem Lett 2024; 15:4197-4205. [PMID: 38598694 DOI: 10.1021/acs.jpclett.4c00608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
Multiresonance thermally activated delayed fluorescence (MR-TADF) emitters are excellent candidates for high-performance organic light-emitting diodes (OLEDs) due to their narrowband emission properties. However, the inherent mechanism of regulating the rate of intersystem crossing (ISC) is ambiguous in certain MR-TADF skeletons. Herein, we propose a mechanism of accelerating ISC in B/S-based MR-TADF emitters by peripheral modifications of electron-donating groups (EDGs) without affecting the narrowband emission property. The long-range charge transfer (LRCT) stems from the introduced EDG leading to high-lying singlet and triplet excited states. The ISC process is accelerated by the enhanced spin-orbital coupling (SOC) between the singlet short-range charge transfer (SRCT) and triplet LRCT manifolds. Meanwhile, the narrowband emission derived from the MR-type SRCT state is well retained as expected in the peripherally modified MR-TADF emitters. This work reveals the regulation mechanism of photophysical properties by high-lying LRCT excited states and provides a significant theoretical basis for modulating the rate of ISC in the further design of MR-TADF materials.
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Affiliation(s)
- Zicong Situ
- State Key Laboratory of Information Photonic and Optical Communications, and School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
| | - Xingqing Li
- State Key Laboratory of Information Photonic and Optical Communications, and School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
| | - Honglei Gao
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, and TIPC-CityU Joint Laboratory of Functional Materials and Device, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiawen Zhang
- State Key Laboratory of Information Photonic and Optical Communications, and School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
| | - Yang Li
- State Key Laboratory of Information Photonic and Optical Communications, and School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
| | - Fangming Zhao
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Jie Kong
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Hongmei Zhao
- State Key Laboratory of Information Photonic and Optical Communications, and School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
| | - Meng Zhou
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Ying Wang
- Key Laboratory of Photochemical Conversion and Optoelectronic Materials, and TIPC-CityU Joint Laboratory of Functional Materials and Device, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhuoran Kuang
- State Key Laboratory of Information Photonic and Optical Communications, and School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
| | - Andong Xia
- State Key Laboratory of Information Photonic and Optical Communications, and School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China
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18
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Ochi J, Yamasaki Y, Tanaka K, Kondo Y, Isayama K, Oda S, Kondo M, Hatakeyama T. Highly efficient multi-resonance thermally activated delayed fluorescence material toward a BT.2020 deep-blue emitter. Nat Commun 2024; 15:2361. [PMID: 38565868 PMCID: PMC10987657 DOI: 10.1038/s41467-024-46619-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 03/01/2024] [Indexed: 04/04/2024] Open
Abstract
An ultrapure deep-blue multi-resonance-induced thermally activated delayed fluorescence material (DOB2-DABNA-A) is designed and synthesized. Benefiting from a fully resonating extended helical π-conjugated system, this compound has a small ΔEST value of 3.6 meV and sufficient spin-orbit coupling to exhibit a high-rate constant for reverse intersystem crossing (kRISC = 1.1 × 106 s-1). Furthermore, an organic light-emitting diode employing DOB2-DABNA-A as an emitter is fabricated; it exhibits ultrapure deep-blue emission at 452 nm with a small full width at half maximum of 24 nm, corresponding to Commission Internationale de l'Éclairage (CIE) coordinates of (0.145, 0.049). The high kRISC value reduces the efficiency roll-off, resulting in a high external quantum efficiency (EQE) of 21.6% at 1000 cd m-2.
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Affiliation(s)
- Junki Ochi
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Yuki Yamasaki
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan
| | - Kojiro Tanaka
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Yasuhiro Kondo
- SK JNC Japan Co., Ltd., 5-1 Goi Kaigan, Ichihara, Chiba, 290-8551, Japan
| | - Kohei Isayama
- SK JNC Japan Co., Ltd., 5-1 Goi Kaigan, Ichihara, Chiba, 290-8551, Japan
| | - Susumu Oda
- Department of Applied Chemistry, Graduate School of Science and Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama, 350-8585, Japan
| | - Masakazu Kondo
- JNC Co., Ltd., 5-1 Goi Kaigan, Ichihara, Chiba, 290-8551, Japan
| | - Takuji Hatakeyama
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan.
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19
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Cho HH, Congrave DG, Gillett AJ, Montanaro S, Francis HE, Riesgo-Gonzalez V, Ye J, Chowdury R, Zeng W, Etherington MK, Royakkers J, Millington O, Bond AD, Plasser F, Frost JM, Grey CP, Rao A, Friend RH, Greenham NC, Bronstein H. Suppression of Dexter transfer by covalent encapsulation for efficient matrix-free narrowband deep blue hyperfluorescent OLEDs. NATURE MATERIALS 2024; 23:519-526. [PMID: 38480865 PMCID: PMC10990937 DOI: 10.1038/s41563-024-01812-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 01/18/2024] [Indexed: 03/21/2024]
Abstract
Hyperfluorescence shows great promise for the next generation of commercially feasible blue organic light-emitting diodes, for which eliminating the Dexter transfer to terminal emitter triplet states is key to efficiency and stability. Current devices rely on high-gap matrices to prevent Dexter transfer, which unfortunately leads to overly complex devices from a fabrication standpoint. Here we introduce a molecular design where ultranarrowband blue emitters are covalently encapsulated by insulating alkylene straps. Organic light-emitting diodes with simple emissive layers consisting of pristine thermally activated delayed fluorescence hosts doped with encapsulated terminal emitters exhibit negligible external quantum efficiency drops compared with non-doped devices, enabling a maximum external quantum efficiency of 21.5%. To explain the high efficiency in the absence of high-gap matrices, we turn to transient absorption spectroscopy. It is directly observed that Dexter transfer from a pristine thermally activated delayed fluorescence sensitizer host can be substantially reduced by an encapsulated terminal emitter, opening the door to highly efficient 'matrix-free' blue hyperfluorescence.
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Affiliation(s)
- Hwan-Hee Cho
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | - Daniel G Congrave
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK.
| | | | - Stephanie Montanaro
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Haydn E Francis
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
- The Faraday Institution, Quad One, Harwell Science and Innovation Campus, Didcot, UK
| | - Víctor Riesgo-Gonzalez
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
- The Faraday Institution, Quad One, Harwell Science and Innovation Campus, Didcot, UK
| | - Junzhi Ye
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | | | - Weixuan Zeng
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Marc K Etherington
- Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Ellison Place, Newcastle upon Tyne, UK
| | - Jeroen Royakkers
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Oliver Millington
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Andrew D Bond
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Felix Plasser
- Department of Chemistry, Loughborough University, Loughborough, UK
| | | | - Clare P Grey
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
- The Faraday Institution, Quad One, Harwell Science and Innovation Campus, Didcot, UK
| | - Akshay Rao
- Cavendish Laboratory, University of Cambridge, Cambridge, UK
| | | | - Neil C Greenham
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
| | - Hugo Bronstein
- Cavendish Laboratory, University of Cambridge, Cambridge, UK.
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK.
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20
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Kage Y, Jiang Y, Minakuchi N, Mori S, Shimizu S. One-pot synthesis of azabora[6]helicene by a Schiff base forming reaction. Chem Commun (Camb) 2024; 60:3543-3546. [PMID: 38454887 DOI: 10.1039/d4cc00168k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2024]
Abstract
Azabora[6]helicene as a new heterohelicene analogue was synthesized by a one-pot reaction of commercially available 2,6-diaminopyridine and benzo[c,d]indole-2(1H)-one and subsequent boron coordination. While the single-crystal X-ray diffraction analysis elucidated a helical structure in the solid state, a dynamic helicity inversion was observed in solution.
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Affiliation(s)
- Yuto Kage
- Department of Applied Chemistry, Graduate School of Engineering and Centre for Molecular Systems, Kyushu University, Fukuoka 819-0395, Japan.
| | - Yuchuan Jiang
- Department of Applied Chemistry, Graduate School of Engineering and Centre for Molecular Systems, Kyushu University, Fukuoka 819-0395, Japan.
| | - Namiki Minakuchi
- Department of Applied Chemistry, Graduate School of Engineering and Centre for Molecular Systems, Kyushu University, Fukuoka 819-0395, Japan.
| | - Shigeki Mori
- Advanced Research Support Centre (ADRES), Ehime University, Matsuyama 790-8577, Japan
| | - Soji Shimizu
- Department of Applied Chemistry, Graduate School of Engineering and Centre for Molecular Systems, Kyushu University, Fukuoka 819-0395, Japan.
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21
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Yang H, Chen G, Zhang R, Zhu Y, Xiao J. Coumarin-embedded [5]helicene derivatives: synthesis, X-ray analysis and photoconducting properties. NANOSCALE 2024; 16:5395-5400. [PMID: 38376253 DOI: 10.1039/d3nr05887e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/21/2024]
Abstract
Two novel coumarin-embedded π-extended [5]helicene derivatives (3a and 6a) have been strategically synthesized and characterized, and the structure of 3a was determined via single crystal X-ray analysis. Both of them exhibit green fluorescence in dichloromethane. In addition, molecule 3a can aggregate to form a large quantity of nanowires through the re-precipitation method. More importantly, the photoelectric conversion properties of 3a nanowire-C60 based films are much better than those of the thin film of bulk 3a-C60, indicating that the ordered nanostructures are a crucial factor for enhancing device performance.
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Affiliation(s)
- Hui Yang
- College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P. R. China.
| | - Guofeng Chen
- College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P. R. China.
| | - Ran Zhang
- College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P. R. China.
| | - Yanjie Zhu
- College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P. R. China.
| | - Jinchong Xiao
- College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P. R. China.
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22
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Mamada M, Hayakawa M, Ochi J, Hatakeyama T. Organoboron-based multiple-resonance emitters: synthesis, structure-property correlations, and prospects. Chem Soc Rev 2024; 53:1624-1692. [PMID: 38168795 DOI: 10.1039/d3cs00837a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Boron-based multiple-resonance (MR) emitters exhibit the advantages of narrowband emission, high absolute photoluminescence quantum yield, thermally activated delayed fluorescence (TADF), and sufficient stability during the operation of organic light-emitting diodes (OLEDs). Thus, such MR emitters have been widely applied as blue emitters in triplet-triplet-annihilation-driven fluorescent devices used in smartphones and televisions. Moreover, they hold great promise as TADF or terminal emitters in TADF-assisted fluorescence or phosphor-sensitised fluorescent OLEDs. Herein we comprehensively review organoboron-based MR emitters based on their synthetic strategies, clarify structure-photophysical property correlations, and provide design guidelines and future development prospects.
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Affiliation(s)
- Masashi Mamada
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
| | - Masahiro Hayakawa
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
| | - Junki Ochi
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
| | - Takuji Hatakeyama
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
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23
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Zender E, Karger S, Neubaur R, Virovets A, Lerner HW, Wagner M. Green-Emitting Extended B 3,N 2-Doped Polycyclic Aromatic Hydrocarbon with Multiple Resonance Structure. Org Lett 2024; 26:939-944. [PMID: 38266241 DOI: 10.1021/acs.orglett.3c04283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
An air-stable B3,N2-PAH (B3N2; nine annulated six-membered rings) was synthesized from 1-X-2,6-di(azasilaanthryl)benzenes (X = Cl, I) via lithiation/borylation, electrophilic aromatic borylation, and Si/B exchange. The heteroatom distribution in B3N2 meets the requirements for multiple resonance thermally activated delayed fluorescence (MR-TADF). Indeed, B3N2 emits green light (λem = 523 nm; ΦPL = 85%; CHCl3) with a small fwhm of 0.15 eV. Lifetimes for prompt (7.8 ns) and delayed (60 μs) fluorescence were measured in PMMA.
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Affiliation(s)
- Elena Zender
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany
| | - Sebastian Karger
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany
| | - Robert Neubaur
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany
| | - Alexander Virovets
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany
| | - Hans-Wolfram Lerner
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany
| | - Matthias Wagner
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt, Max-von-Laue-Straße 7, D-60438 Frankfurt (Main), Germany
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24
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Meng G, Zhou J, Han XS, Zhao W, Zhang Y, Li M, Chen CF, Zhang D, Duan L. B-N Covalent Bond Embedded Double Hetero-[n]helicenes for Pure Red Narrowband Circularly Polarized Electroluminescence with High Efficiency and Stability. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2307420. [PMID: 37697624 DOI: 10.1002/adma.202307420] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 08/22/2023] [Indexed: 09/13/2023]
Abstract
Chiral B/N embedded multi-resonance (MR) emitters open a new paradigm of circularly polarized (CP) organic light-emitting diodes (OLEDs) owing to their unique narrowband spectra. However, pure-red CP-MR emitters and devices remain exclusive in literature. Herein, by introducing a B-N covalent bond to lower the electron-withdrawing ability of the para-positioned B-π-B motif, the first pair of pure-red double hetero-[n]helicenes (n = 6 and 7) CP-MR emitter peaking 617 nm with a small full-width at half-maximum of 38 nm and a high photoluminescence quantum yield of ≈100% in toluene is developed. The intense mirror-image CP light produced by the enantiomers is characterized by high photoluminescence dissymmetry factors (gPL ) of +1.40/-1.41 × 10-3 from their stable helicenes configuration. The corresponding devices using these enantiomers afford impressive CP electroluminescence dissymmetry factors (gEL ) of +1.91/-1.77 × 10-3 , maximum external quantum efficiencies of 36.6%/34.4% and Commission Internationale de I'Éclairage coordinates of (0.67, 0.33), exactly satisfying the red-color requirement specified by National Television Standards Committee (NTSC) standard. Notably a remarkable long LT95 (operational time to 95% of the initial luminance) of ≈400 h at an initial brightness of 10,000 cd m-2 is also observed for the same device, representing the most stable CP-OLED up to date.
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Affiliation(s)
- Guoyun Meng
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Jianping Zhou
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Xu-Shuang Han
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Wenlong Zhao
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Yuewei Zhang
- Laboratory of Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
| | - Meng Li
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Chuan-Feng Chen
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Dongdong Zhang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
- Laboratory of Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
| | - Lian Duan
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
- Laboratory of Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
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25
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Luo XF, Xiao X, Zheng YX. Recent progress in multi-resonance thermally activated delayed fluorescence emitters with an efficient reverse intersystem crossing process. Chem Commun (Camb) 2024; 60:1089-1099. [PMID: 38175168 DOI: 10.1039/d3cc05460h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Multi-resonance thermally activated delayed fluorescence (MR-TADF) emitters have become an active research topic at the forefront of organic light-emitting diodes (OLEDs) owing to their excellent photophysical properties such as high efficiency and narrow emission characteristics. However, MR-TADF materials always exhibit slow reverse intersystem crossing rates (kRISC) due to the large energy gap and small spin-orbit coupling values between singlet and triplet excited states. In order to optimize the RISC process, strategies such as heavy-atom-integration, metal perturbation, π-conjugation extension and peripheral decoration of donor/acceptor units have been proposed to construct efficient MR-TADF materials for high-performance OLEDs. This article provides an overview of the recent progress in MR-TADF emitters with an efficient RISC process, focusing on the structure-activity relationship between the molecular structure, optoelectronic feature, and OLED performance. Finally, the potential challenges and future prospects of MR-TADF materials are discussed to gain a more comprehensive understanding of the opportunities for efficient narrowband OLEDs.
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Affiliation(s)
- Xu-Feng Luo
- College of Material Science and Chemical Engineering, Ningbo University of Technology, Ningbo 315211, P. R. China.
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China.
| | - Xunwen Xiao
- College of Material Science and Chemical Engineering, Ningbo University of Technology, Ningbo 315211, P. R. China.
| | - You-Xuan Zheng
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China.
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26
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Khalid MI, Salem MSH, Takizawa S. Synthesis and Structural and Optical Behavior of Dehydrohelicene-Containing Polycyclic Compounds. Molecules 2024; 29:296. [PMID: 38257209 PMCID: PMC10819569 DOI: 10.3390/molecules29020296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 12/28/2023] [Accepted: 01/03/2024] [Indexed: 01/24/2024] Open
Abstract
Dehydrohelicene-based molecules stand out as highly promising scaffolds and captivating chiroptical materials, characterized by their unique chirality. Their quasi-helical π-conjugated molecular architecture, featuring successively ortho-annulated aromatic rings, endows them with remarkable thermal stability and optical properties. Over the past decade, diverse approaches have emerged for synthesizing these scaffolds, reinvigorating this field, with anticipated increased attention in the coming years. This review provides a comprehensive overview of the historical evolution of dehydrohelicene chemistry since the pioneering work of Zander and Franke in 1969 and highlights recent advancements in the synthesis of various molecules incorporating dehydrohelicene motifs. We elucidate the intriguing structural features and optical merits of these molecules, occasionally drawing comparisons with their helicene or circulene analogs to underscore the significance of the bond between the helical termini.
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Affiliation(s)
- Md. Imrul Khalid
- SANKEN, Osaka University, Mihogaoka, Ibaraki-shi 567-0047, Osaka, Japan; (M.I.K.); (M.S.H.S.)
- Organic and Carbon Nanomaterials Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa 904-0495, Japan
| | - Mohamed S. H. Salem
- SANKEN, Osaka University, Mihogaoka, Ibaraki-shi 567-0047, Osaka, Japan; (M.I.K.); (M.S.H.S.)
- Pharmaceutical Organic Chemistry Department, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt
| | - Shinobu Takizawa
- SANKEN, Osaka University, Mihogaoka, Ibaraki-shi 567-0047, Osaka, Japan; (M.I.K.); (M.S.H.S.)
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27
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Avula S, Jhun BH, Jo U, Heo S, Lee JY, You Y. Achieving Long-Wavelength Electroluminescence Using Two-Coordinate Gold(I) Complexes: Overcoming the Energy Gap Law. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2305745. [PMID: 37953418 PMCID: PMC10767458 DOI: 10.1002/advs.202305745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/05/2023] [Indexed: 11/14/2023]
Abstract
Two-coordinate coinage metal complexes have emerged as promising emitters for highly efficient organic light-emitting devices (OLEDs). However, achieving efficient long-wavelength electroluminescence emission from these complexes remains as a daunting challenge. To address this challenge, molecular design strategies aimed at bolstering the photoluminescence quantum yield (Φ) of Au(I) complex emitters in low-energy emission regions are investigated. By varying amido ligands, a series of two-coordinate Au(I) complexes is developed that exhibit photoluminescence peak wavelengths over a broad range of 533-750 nm. These complexes, in particular, maintain Φ values up to 10% even in the near-infrared emission region, overcoming the constraints imposed by an energy gap. Quantum chemical calculations and photophysical analyses reveal the action of radiative control, which serves to overcome the energy gap law, becomes more pronounced as the overlap between hole and electron distributions (Sr (r)) in the excited state increases. It is further elucidated that Sr (r) increases with the distance between the hole-distribution centroid and the nitrogen atom in an amido ligand. Finally, multilayer OLEDs involving the Au(I) complex emitters exhibit performances beyond the borderline of the electroluminescence wavelength-external quantum efficiency space set by previous devices of coinage metal complexes.
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Affiliation(s)
- Sreenivas Avula
- Department of Chemical and Biomolecular EngineeringYonsei UniversitySeoul03722Republic of Korea
| | - Byung Hak Jhun
- Department of Chemical and Biomolecular EngineeringYonsei UniversitySeoul03722Republic of Korea
| | - Unhyeok Jo
- School of Chemical EngineeringSungkyunkwan UniversitySuwonGyeonggi‐do16419Republic of Korea
| | - Seunga Heo
- Division of Chemical Engineering and Materials ScienceEwha Womans UniversitySeoul03760Republic of Korea
| | - Jun Yeob Lee
- School of Chemical EngineeringSungkyunkwan UniversitySuwonGyeonggi‐do16419Republic of Korea
| | - Youngmin You
- Department of Chemical and Biomolecular EngineeringYonsei UniversitySeoul03722Republic of Korea
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28
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Ye Z, Wu H, Xu Y, Hua T, Chen G, Chen Z, Yin X, Huang M, Xu K, Song X, Huang Z, Lv X, Miao J, Cao X, Yang C. Deep-Blue Narrowband Hetero[6]helicenes Showing Circularly Polarized Thermally Activated Delayed Fluorescence Toward High-Performance OLEDs. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2308314. [PMID: 37963185 DOI: 10.1002/adma.202308314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/18/2023] [Indexed: 11/16/2023]
Abstract
Helicenes exhibit substantial potential as circularly polarized luminescence (CPL) active molecules. However, their application in circularly polarized organic light-emitting diodes (CP-OLEDs) is typically hindered by the challenge of integrating both high color purity and efficient triplet-harvesting capability, particularly in the blue spectral region. Herein, a series of hetero[6]helicene-based emitters that is strategically engineered through the helical extension of a deep-blue double-boron-based multiple resonance thermally activated delayed fluorescence (MR-TADF) motif, is introduced. Importantly, the helical extension does not cause apparent structural deformation or perturb frontier molecular orbitals; thus, preserving the deep-blue emission and MR-TADF characteristics of the parent molecule. This approach also leads to reduced reorganization energy, resulting in emitters with narrower linewidth and higher photoluminescence quantum yield. Further, the helical motif enhances the racemization barrier and leads to improved CPL performance with luminescence dissymmetry factor values up to 1.5 × 10-3 . Exploiting these merits, devices incorporating the chiral dopants demonstrate deep-blue emission within the Broadcast Service Television 2020 color-gamut range, record external quantum efficiencies (EQEs) up to 29.3%, and have distinctive circularly polarized electroluminescence (CPEL) signals. Overall, the authors' findings underscore the helical extension as a promising strategy for designing narrowband chiroptical materials and advancing high-definition displays.
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Affiliation(s)
- Zeyuan Ye
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Han Wu
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Yulin Xu
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Tao Hua
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Guohao Chen
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Zhanxiang Chen
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Xiaojun Yin
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Manli Huang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Ke Xu
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Xiufang Song
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Zhongyan Huang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Xialei Lv
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Jingsheng Miao
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Xiaosong Cao
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Chuluo Yang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, China
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29
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Yamada K, Adachi Y, Ohshita J. Synthesis and Properties of Boron-Containing Heteromerous Bistricyclic Aromatic Enes: Structural Effects on Thermodynamic Stability and Photoreactivity. Chemistry 2023; 29:e202302370. [PMID: 37793988 DOI: 10.1002/chem.202302370] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 10/04/2023] [Accepted: 10/04/2023] [Indexed: 10/06/2023]
Abstract
Overcrowded bistricyclic aromatic enes (BAEs) have several conformations such as twisted and anti-folded conformers, and their stereochemistry and chromism have been studied in earnest. In this study, boron-containing heteromerous BAEs having various tricyclic structures were synthesized and their photophysical properties investigated. Single-crystal X-ray analysis revealed that the introduction of a rigid fluorene unit resulted in a twisted conformer, whereas the introduction of flexible units such as thioxanthene and 9,9-dimethyl-9,10-dihydroanthracene units resulted in an anti-folded conformer. The absorption spectra of the heteromerous BAEs were dependent on the introduced tricyclic structures, suggesting the immense impact of the tricyclic structures on the electronic structures of BAEs. DFT calculations revealed the large effect of the flexibility of the tricyclic structures on the thermodynamic stability of the conformers. In addition, the boron-containing heteromerous BAEs underwent photocyclization reactions, indicating their potential application as precursors of polyaromatic hydrocarbons and helical aromatic materials.
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Affiliation(s)
- Kohei Yamada
- Smart Innovation Program, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima, 739-8527, Japan
| | - Yohei Adachi
- Smart Innovation Program, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima, 739-8527, Japan
| | - Joji Ohshita
- Smart Innovation Program, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima, Hiroshima, 739-8527, Japan
- Division of Materials Model-Based Research, Digital Monozukuri (Manufacturing) Education and Research Center, Hiroshima University, Higashi-Hiroshima, Hiroshima, 739-8527, Japan
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30
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Xu Y, Wang Q, Cai X, Li C, Jiang S, Wang Y. Frontier Molecular Orbital Engineering: Constructing Highly Efficient Narrowband Organic Electroluminescent Materials. Angew Chem Int Ed Engl 2023; 62:e202312451. [PMID: 37724466 DOI: 10.1002/anie.202312451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/18/2023] [Accepted: 09/19/2023] [Indexed: 09/20/2023]
Abstract
It is of great strategic significance to develop highly efficient narrowband organic electroluminescent materials that can be utilized to manufacture ultra-high-definition (UHD) displays and meet or approach the requirements of Broadcast Television 2020 (B.T.2020) color gamut standards. This motif poses challenges for molecular design and synthesis, especially for developing generality, diversity, scalability, and robustness of molecular structures. The emergence of multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters has ingeniously solved the problems and demonstrated bright application prospects in the field of UHD displays, sparking a research boom. This Minireview summarizes the research endeavors of narrowband organic electroluminescent materials, with emphasis on the tremendous contribution of frontier molecular orbital engineering (FMOE) strategy. It combines the outstanding advantages of MR framework and donor-acceptor (D-A) structure, and can achieve red-shift and narrowband emission simultaneously, which is of great significance in the development of long-wavelength narrowband emitters with emission maxima especially exceeding 500 nm. We hope that this Minireview would provide some inspiration for what could transpire in the future.
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Affiliation(s)
- Yincai Xu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Qingyang Wang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Xinliang Cai
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Chenglong Li
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Shimei Jiang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Yue Wang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
- Jihua Hengye Electronic Materials CO. LTD., Foshan, 528200, Guangdong Province, P. R. China
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31
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Kothavale S, Iqbal SA, Hanover EL, Gupta AK, Zysman-Colman E, Ingleson MJ. Borylation-Reduction-Borylation for the Formation of 1,4-Azaborines. Org Lett 2023; 25:8912-8916. [PMID: 38055858 PMCID: PMC10729022 DOI: 10.1021/acs.orglett.3c03731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 12/08/2023]
Abstract
Given the current interest in materials containing 1,4-azaborine units, the development of new routes to these structures is important. Carbonyl directed electrophilic borylation using BBr3 is a facile method for the ortho-borylation of N,N-diaryl-amide derivatives. Subsequent addition of Et3SiH results in carbonyl reduction and then formation of 1,4-azaborines that can be protected in situ using a Grignard reagent. Overall, borylation-reduction-borylation is a one-pot methodology to access 1,4-azaborines from simple precursors.
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Affiliation(s)
- Shantaram
S. Kothavale
- EaStCHEM
School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Saqib A. Iqbal
- EaStCHEM
School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Emily L. Hanover
- EaStCHEM
School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
- Organic
Semiconductor Centre and EaStCHEM School of Chemistry, University of St Andrews, St Andrews KY16 9ST, United Kingdom
| | - Abhishek K. Gupta
- Organic
Semiconductor Centre and EaStCHEM School of Chemistry, University of St Andrews, St Andrews KY16 9ST, United Kingdom
| | - Eli Zysman-Colman
- Organic
Semiconductor Centre and EaStCHEM School of Chemistry, University of St Andrews, St Andrews KY16 9ST, United Kingdom
| | - Michael J. Ingleson
- EaStCHEM
School of Chemistry, The University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
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32
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Matsuo Y, Maeda C, Tsutsui Y, Tanaka T, Seki S. Synthesis of Closed-Heterohelicenes Interconvertible between Their Monomeric and Dimeric Forms. Angew Chem Int Ed Engl 2023; 62:e202314968. [PMID: 37883214 DOI: 10.1002/anie.202314968] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 10/28/2023]
Abstract
Oxidative fusion reaction of cyclic heteroaromatic pentads consisting of pyrrole and thiophene gave closed-heterohelicene monomers and dimers depending on the oxidation conditions. Specifically, oxidation with [bis(trifluoroacetoxy)iodo]benzene (PIFA) gave closed-[7]helicene dimers connected at the β-position of one of the pyrrole units with remarkably elongated C-C bonds of about 1.60 Å. Although this bond was intact against thermal and physical activations, homolytic bond dissociation took place in DMSO upon irradiation with UV light to give the corresponding monomers. Thus, interconversion between the closed-helicene monomer and dimer was achieved. The optically pure dimer was photo-dissociated into the monomers associated with a turn-on of circularly polarized luminescence (CPL).
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Affiliation(s)
- Yusuke Matsuo
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Chihiro Maeda
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama 700-8530, Japan
| | - Yusuke Tsutsui
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
- JST-PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Takayuki Tanaka
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Shu Seki
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
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Ma P, Chen Y, Man Y, Qi Q, Guo Y, Wang H, Li Z, Chang P, Qu C, Han C, Xu H. High-Efficiency Ultraviolet Electroluminescence from Multi-Resonance Phosphine Oxide Polycyclic Aromatics. Angew Chem Int Ed Engl 2023:e202316479. [PMID: 38055193 DOI: 10.1002/anie.202316479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/27/2023] [Accepted: 12/05/2023] [Indexed: 12/07/2023]
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 nm 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, a novel MR-TADF skeleton featuring carbazole-phosphine oxide (P=O) fused aromatics is developed to construct the first two UV MR emitters named CzP2PO and tBCzP2PO. In addition to synergistic resonance effects of P=O and N atom, sp3 -hybrid P atom renders the curved polycyclic planes of CzP2PO and tBCzP2PO, giving rise to their narrowband UV emissions with peak wavelengths <390 nm and FWHM<35 nm. Besides configuration quasi-planarization for radiation enhancement and quenching suppression, P=O moiety further enhances singlet-triplet coupling to facilitate reverse intersystem crossing, resulting in the state-of-the-art photoluminescence quantum yield of 62 % in tBCzP2PO doped films. As consequence, tBCzP2PO endowed its UV organic light-emitting diodes with the peak at 382 nm and FWHM of 32 nm, and especially the record-high external quantum efficiency (EQE) of 15.1 % among all kinds of UV devices. Our results demonstrate great potential of P=O based MR emitters in practical applications including optoelectronics, biology and medicine science.
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Affiliation(s)
- Peng Ma
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Yingying Chen
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Yi Man
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Quan Qi
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Yuanting Guo
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Huiqin Wang
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Zhe Li
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Peng Chang
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Chao Qu
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Chunmiao Han
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
| | - Hui Xu
- Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials, Heilongjiang University, Harbin, Heilongjiang, 150080, China
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Luo S, Wang J, Li N, Song XF, Wan X, Li K, Yang C. Regulation of Multiple Resonance Delayed Fluorescence via Through-Space Charge Transfer Excited State towards High-Efficiency and Stable Narrowband Electroluminescence. Angew Chem Int Ed Engl 2023; 62:e202310943. [PMID: 37851366 DOI: 10.1002/anie.202310943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 10/17/2023] [Accepted: 10/18/2023] [Indexed: 10/19/2023]
Abstract
B- and N-embedded multiple resonance (MR) type thermally activated delayed fluorescence (TADF) emitters usually suffer from slow reverse intersystem crossing (RISC) process and aggregation-caused emission quenching. Here, we report the design of a sandwich structure by placing the B-N MR core between two electron-donating moieties, inducing through-space charge transfer (TSCT) states. The proper adjusting of the energy levels brings about a 10-fold higher RISC rate in comparison with the parent B-N molecule. In the meantime, a high photoluminescence quantum yield of 91 % and a good color purity were maintained. Organic light-emitting diodes based on the new MR emitter achieved a maximum external quantum efficiency of 31.7 % and small roll-offs at high brightness. High device efficiencies were also obtained for a wide range of doping concentrations of up to 20 wt % thanks to the steric shielding of the B-N core. A good operational stability with LT95 of 85.2 h has also been revealed. The dual steric and electronic effects resulting from the introduction of a TSCT state offer an effective molecular design to address the critical challenges of MR-TADF emitters.
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Affiliation(s)
- Sai Luo
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, 518055, Shenzhen, P. R. China
| | - Junjie Wang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, 518055, Shenzhen, P. R. China
| | - Nengquan Li
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, 518055, Shenzhen, P. R. China
| | - Xiu-Fang Song
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, 518055, Shenzhen, P. R. China
| | - Xintong Wan
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, 518055, Shenzhen, P. R. China
| | - Kai Li
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, 518055, Shenzhen, P. R. China
| | - Chuluo Yang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, 518055, Shenzhen, P. R. China
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Zhang K, Wang X, Chang Y, Wu Y, Wang S, Wang L. Carbazole-Decorated Organoboron Emitters with Low-Lying HOMO Levels for Solution-Processed Narrowband Blue Hyperfluorescence OLED Devices. Angew Chem Int Ed Engl 2023; 62:e202313084. [PMID: 37775994 DOI: 10.1002/anie.202313084] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 09/28/2023] [Accepted: 09/29/2023] [Indexed: 10/01/2023]
Abstract
The hyperfluorescence has drawn great attention in achieving efficient narrowband emitting devices based on multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters. However, achieving efficient solution-processed pure blue hyperfluorescence devices is still a challenge, due to the unbalanced charge transport and serious exciton quenching caused by that the holes are easily trapped on the high-lying HOMO (the highest occupied molecular orbital) level of traditional diphenylamine-decorated emitters. Here, we developed two narrowband blue organoboron emitters with low-lying HOMO levels by decorating the MR-TADF core with weakly electron-donating carbazoles, which could suppress the hole trapping effect by reducing the hole traps between host and MR-TADF emitter from deep (0.40 eV) to shallow (0.14/0.20 eV) ones for facilitating hole transport and exciton formation, as well as avoiding exciton quenching. And the large dihedral angle between the carbazole and MR-TADF core makes the carbazole act as a steric hindrance to inhibit molecular aggregation. Accordingly, the optimized solution-processed pure blue hyperfluorescence devices simultaneously realize record external quantum efficiency of 29.2 %, narrowband emission with a full-width at half-maximum of 16.6 nm, and pure blue color with CIE coordinates of (0.139, 0.189), which is the best result for the solution-processed organic light-emitting diodes based on MR-TADF emitters.
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Affiliation(s)
- Kaiyuan Zhang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, P. R. China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, 230026, Hefei, P. R. China
| | - Xingdong Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, P. R. China
| | - Yufei Chang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, P. R. China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, 230026, Hefei, P. R. China
| | - Yuliang Wu
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, P. R. China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, 230026, Hefei, P. R. China
| | - Shumeng Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, P. R. China
| | - Lixiang Wang
- State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022, Changchun, P. R. China
- School of Applied Chemistry and Engineering, University of Science and Technology of China, 230026, Hefei, P. R. China
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Meng G, Zhou J, Huang T, Dai H, Li X, Jia X, Wang L, Zhang D, Duan L. B-N/B-O Contained Heterocycles as Fusion Locker in Multi-Resonance Frameworks towards Highly-efficient and Stable Ultra-Narrowband Emission. Angew Chem Int Ed Engl 2023; 62:e202309923. [PMID: 37584379 DOI: 10.1002/anie.202309923] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 08/10/2023] [Accepted: 08/11/2023] [Indexed: 08/17/2023]
Abstract
Fusing condensed aromatics into multi-resonance (MR) frameworks has been an exquisite strategy to modulate the optoelectronic properties, which, however, always sacrifices the small full width at half maxima (FWHM). Herein, we strategically embed B-N/B-O contained heterocycles as fusion locker into classical MR prototypes, which could enlarge the π-extension and alleviate the steric repulsion for an enhanced planar skeleton to suppress the high-frequency stretching/ scissoring vibrations for ultra-narrowband emissions. Sky-blue emitters with extremely small FWHMs of 17-18 nm are thereafter obtained for the targeted emitters, decreased by (1.4-1.9)-fold compared with the prototypes. Benefiting from their high photoluminescence quantum yields of >90 % and fast radiative decay rates of >108 s-1 , one of those emitters shows a high maximum external quantum efficiency of 31.9 % in sensitized devices, which remains 25.8 % at a practical luminance of 1,000 cd m-2 with a small FWHM of merely 19 nm. Notably a long operation half-lifetime of 1,278 h is also recorded for the same device, representing one of the longest lifetimes among sky-blue devices based on MR emitters.
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Affiliation(s)
- Guoyun Meng
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Jianping Zhou
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Tianyu Huang
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Hengyi Dai
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Xiao Li
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Xiaoqin Jia
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Lu Wang
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Dongdong Zhang
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Lian Duan
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
- Center for Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
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Hou P, Xu Y, Miao J, Zhu M, Liu H. Naphthalene-Embedded Multi-Resonance Emitters Enabling Efficient Narrow Emissive Blue OLEDs. Chemistry 2023; 29:e202301931. [PMID: 37423895 DOI: 10.1002/chem.202301931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/04/2023] [Accepted: 07/04/2023] [Indexed: 07/11/2023]
Abstract
Great achievements have been made in the development of organic light-emitting diodes in recent decades. However, achieving high color purity for blue emitters remains a challenge. In this study, we have designed and synthesized three naphthalene (NA)-embedded multi-resonance (MR) emitters, named SNA, SNB and SNB1, based on N-B-O frameworks with isomer variations for finely adjusting the photophysical properties. These emitters show tunable blue emission with emission peaks of 450-470 nm. Small full width of half maximum (FWHM) of 25-29 nm are achieved in these emitters, indicating the well maintaining of molecular rigidity and MR effect with NA extension. Such design also ensures a fast radiative decay. However, no obvious delayed fluorescence is observed in all three emitters due to the relatively large energy differences between the first singlet and triplet excited states. Both SNA and SNB enable high electroluminescent (EL) performance in doped devices with external quantum efficiency (EQE) of 7.2 and 7.9 %, respectively. When applying the sensitized strategy, devices based on SNA and SNB show huge improvement with EQE of 29.3 and 29.1 %. More importantly, SNB with twist geometry enables stable EL spectra with almost unchanged FWHM under different doping concentrations. This work demonstrates the potential of NA extension design in constructing narrowband emissive blue emitters.
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Affiliation(s)
- Peijie Hou
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518055, P. R. China
| | - Yulin Xu
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518055, P. R. China
| | - Jingsheng Miao
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518055, P. R. China
| | - Minrong Zhu
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518055, P. R. China
| | - He Liu
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518055, P. R. China
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Yu YJ, Feng ZQ, Meng XY, Chen L, Liu FM, Yang SY, Zhou DY, Liao LS, Jiang ZQ. Introducing Spiro-locks into the Nitrogen/Carbonyl System towards Efficient Narrowband Deep-blue Multi-resonance TADF Emitters. Angew Chem Int Ed Engl 2023; 62:e202310047. [PMID: 37593817 DOI: 10.1002/anie.202310047] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/15/2023] [Accepted: 08/16/2023] [Indexed: 08/19/2023]
Abstract
The current availability of multi-resonance thermally activated delayed fluorescence (MR-TADF) materials with excellent color purity and high device efficiency in the deep-blue region is appealing. To address this issue in the emerged nitrogen/carbonyl MR-TADF system, we propose a spiro-lock strategy. By incorporating spiro functionalization into a concise molecular skeleton, a series of emitters (SFQ, SOQ, SSQ, and SSeQ) can enhance molecular rigidity, blue-shift the emission peak, narrow the emission band, increase the photoluminescence quantum yield by over 92 %, and suppress intermolecular interactions in the film state. The referent CZQ without spiro structure has a more planar skeleton, and its bluer emission in the solution state redshifts over 40 nm with serious spectrum broadening and a low PLQY in the film state. As a result, SSQ achieves an external quantum efficiency of 25.5 % with a peak at 456 nm and a small full width at half maximum of 31 nm in a simple unsensitized device, significantly outperforming CZQ. This work discloses the importance of spiro-junction in modulating deep-blue MR-TADF emitters.
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Affiliation(s)
- You-Jun Yu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 215123, Suzhou, Jiangsu, P. R. China
| | - Zi-Qi Feng
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 215123, Suzhou, Jiangsu, P. R. China
| | - Xin-Yue Meng
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 215123, Suzhou, Jiangsu, P. R. China
| | - Long Chen
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 215123, Suzhou, Jiangsu, P. R. China
| | - Fu-Ming Liu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 215123, Suzhou, Jiangsu, P. R. China
| | - Sheng-Yi Yang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 215123, Suzhou, Jiangsu, P. R. China
| | - Dong-Ying Zhou
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 215123, Suzhou, Jiangsu, P. R. China
| | - Liang-Sheng Liao
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 215123, Suzhou, Jiangsu, P. R. China
- Macao Institute of Materials Science and Engineering, Macau University of Science and Technology, 999078, Taipa, Macau SAR, China
| | - Zuo-Quan Jiang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 215123, Suzhou, Jiangsu, P. R. China
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Fan X, Hao X, Huang F, Yu J, Wang K, Zhang X. RGB Thermally Activated Delayed Fluorescence Emitters for Organic Light-Emitting Diodes toward Realizing the BT.2020 Standard. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2303504. [PMID: 37587784 PMCID: PMC10558656 DOI: 10.1002/advs.202303504] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/25/2023] [Indexed: 08/18/2023]
Abstract
With the surging demand for ultra-high-resolution displays, the International Telecommunication Union (ITU) announce the next-generation color gamut standard, named ITU-R Recommendation BT.2020, which not only sets a seductive but challenging milestone for display technologies but also urges researchers to recognize the importance of color coordinates. Organic light-emitting diodes (OLEDs) are an important display technology in current daily life, but they face challenges in approaching the BT.2020 standard. Thermally activated delayed fluorescence (TADF) emitters have bright prospects in OLEDs because they possess 100% theoretical exciton utilization. Thus, the development of TADF emitters emitting primary red (R), green (R), and blue (B) emission is of great significance. Here, a comprehensive overview of the latest advancements in TADF emitters that exhibit Commission Internationale de l'Éclairage (CIE) coordinates surpassing the National Television System Committee (NTSC) and approaching BT.2020 standards is presented. Rational strategies for molecular designs, as well as the resulting photophysical properties and OLED performances, are discussed to elucidate the underlying mechanisms for shifting the CIE coordinates of both donor-acceptor and multiple resonance (MR) typed TADF emitters toward the BT.2020 standard. Finally, the challenges in realization of the wide-color-gamut BT.2020 standard and the prospects for this research area are provided.
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Affiliation(s)
- Xiaochun Fan
- Institute of Functional Nano & Soft Materials (FUNSOM)Soochow UniversitySuzhouJiangsu215123P. R. China
| | - Xiaoyao Hao
- Institute of Functional Nano & Soft Materials (FUNSOM)Soochow UniversitySuzhouJiangsu215123P. R. China
| | - Feng Huang
- Institute of Functional Nano & Soft Materials (FUNSOM)Soochow UniversitySuzhouJiangsu215123P. R. China
| | - Jia Yu
- Institute of Functional Nano & Soft Materials (FUNSOM)Soochow UniversitySuzhouJiangsu215123P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon TechnologiesSoochow UniversitySuzhouJiangsu215123P. R. China
| | - Kai Wang
- Institute of Functional Nano & Soft Materials (FUNSOM)Soochow UniversitySuzhouJiangsu215123P. R. China
- Jiangsu Key Laboratory of Carbon‐Based Functional Materials and DevicesSoochow UniversitySuzhouJiangsu215123P. R. China
| | - Xiaohong Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM)Soochow UniversitySuzhouJiangsu215123P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon TechnologiesSoochow UniversitySuzhouJiangsu215123P. R. China
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Fan XC, Huang F, Wu H, Wang H, Cheng YC, Yu J, Wang K, Zhang XH. A Quadruple-Borylated Multiple-Resonance Emitter with para/meta Heteroatomic Patterns for Narrowband Orange-Red Emission. Angew Chem Int Ed Engl 2023; 62:e202305580. [PMID: 37431732 DOI: 10.1002/anie.202305580] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/10/2023] [Accepted: 07/11/2023] [Indexed: 07/12/2023]
Abstract
Hindered by spectral broadening issues with redshifted emission, long-wavelength (e.g., maxima beyond 570 nm) multiple resonance (MR) emitters with full width at half maxima (FWHMs) below 20 nm remain absent. Herein, by strategically embedding diverse boron (B)/nitrogen (N) atomic pairs into a polycyclic aromatic hydrocarbon (PAH) skeleton, we propose a hybrid pattern for the construction of a long-wavelength narrowband MR emitter. The proof-of-concept emitter B4N6-Me realized orange-red emission with an extremely small FWHM of 19 nm (energy unit: 70 meV), representing the narrowest FWHM among all reported long-wavelength MR emitters. Theoretical calculations revealed that the cooperation of the applied para B-π-N and para B-π-B/N-π-N patterns is complementary, which gives rise to both narrowband and redshift characteristics. The corresponding organic light-emitting diode (OLED) employing B4N6-Me achieved state-of-the-art performance, e.g., a narrowband orange-red emission with an FWHM of 27 nm (energy unit: 99 meV), an excellent maximum external quantum efficiency (EQE) of 35.8 %, and ultralow efficiency roll-off (EQE of 28.4 % at 1000 cd m-2 ). This work provides new insights into the further molecular design and synthesis of long-wavelength MR emitters.
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Affiliation(s)
- Xiao-Chun Fan
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Feng Huang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Hao Wu
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Hui Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Ying-Chun Cheng
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Jia Yu
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Kai Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Xiao-Hong Zhang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
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Xie FM, Li HZ, Zhang K, Wang HY, Li YQ, Tang JX. Rational Multidimensional Shielded Multiple Resonance Emitter Suppresses Concentration Quenching and Spectral Broadening for Solution-Processed Organic Light-Emitting Diodes. ACS APPLIED MATERIALS & INTERFACES 2023; 15:39669-39676. [PMID: 37579002 DOI: 10.1021/acsami.3c07852] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
Thermally activated delayed fluorescence (TADF) emitters based on multiple resonance (MR) effects are promising for high-definition organic light-emitting diodes (OLEDs) with narrowband emission and high efficiency. However, they still face the challenges of aggregation-caused quenching (ACQ) and spectral broadening. Solution-processable MR-TADF emitters with an external quantum efficiency (EQE) of >20% and a full width at half-maximum (fwhm) of <30 nm have rarely been reported. To construct ACQ-resistant emitters without sacrificing color purity, the aggregation-induced MR-TADF material 6TBN with a rigid B,N-containing polycyclic aromatic hydrocarbon core and four carbazole substituents as well as 12 tert-butyl groups on the periphery is designed. The multidimensional shielded effect largely limits the ACQ, intermolecular interactions, and spectral broadening. Consequently, solution-processed OLEDs based on 6TBN exhibit a maximum EQE of 23.0% and high color purity with a fwhm of 25 nm. Furthermore, the nondoped device achieves a high efficiency (12.3%) and merely a slight widening of the fwhm to 27 nm. This work provides a feasible strategy to achieve MR-TADF materials with resistance to concentration quenching and high color purity.
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Affiliation(s)
- Feng-Ming Xie
- Macao Institute of Materials Science and Engineering (MIMSE), Faculty of Innovation Engineering, Macau University of Science and Technology, Taipa 999078, Macao, People's Republic of China
| | - Hao-Ze Li
- School of Physics and Electronic Science, East China Normal University, Shanghai 200062, People's Republic of China
| | - Kai Zhang
- Macao Institute of Materials Science and Engineering (MIMSE), Faculty of Innovation Engineering, Macau University of Science and Technology, Taipa 999078, Macao, People's Republic of China
| | - Han-Yang Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, People's Republic of China
| | - Yan-Qing Li
- School of Physics and Electronic Science, East China Normal University, Shanghai 200062, People's Republic of China
| | - Jian-Xin Tang
- Macao Institute of Materials Science and Engineering (MIMSE), Faculty of Innovation Engineering, Macau University of Science and Technology, Taipa 999078, Macao, People's Republic of China
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, People's Republic of China
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42
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Suresh SM, Zhang L, Matulaitis T, Hall D, Si C, Ricci G, Slawin AMZ, Warriner S, Beljonne D, Olivier Y, Samuel IDW, Zysman-Colman E. Judicious Heteroatom Doping Produces High-Performance Deep-Blue/Near-UV Multiresonant Thermally Activated Delayed Fluorescence OLEDs. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2300997. [PMID: 37140188 DOI: 10.1002/adma.202300997] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/26/2023] [Indexed: 05/05/2023]
Abstract
Two multiresonant thermally activated delayed fluorescence (MR-TADF) emitters are presented and it is shown how further borylation of a deep-blue MR-TADF emitter, DIDOBNA-N, both blueshifts and narrows the emission producing a new near-UV MR-TADF emitter, MesB-DIDOBNA-N, are shown. DIDOBNA-N emits bright blue light (ΦPL = 444 nm, FWHM = 64 nm, ΦPL = 81%, τd = 23 ms, 1.5 wt% in TSPO1). The deep-blue organic light-emitting diode (OLED) based on this twisted MR-TADF compound shows a very high maximum external quantum efficiency (EQEmax ) of 15.3% for a device with CIEy of 0.073. The fused planar MR-TADF emitter, MesB-DIDOBNA-N shows efficient and narrowband near-UV emission (λPL = 402 nm, FWHM = 19 nm, ΦPL = 74.7%, τd = 133 ms, 1.5 wt% in TSPO1). The best OLED with MesB-DIDOBNA-N, doped in a co-host, shows the highest efficiency reported for a near-UV OLED at 16.2%. With a CIEy coordinate of 0.049, this device also shows the bluest EL reported for a MR-TADF OLED to date.
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Affiliation(s)
- Subeesh Madayanad Suresh
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - Le Zhang
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
- Organic Semiconductor Centre, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, KY16 9SS, UK
| | - Tomas Matulaitis
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - David Hall
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
- Laboratory for Chemistry of Novel Materials, University of Mons, Mons, 7000, Belgium
| | - Changfeng Si
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - Gaetano Ricci
- Laboratory for Computational Modeling of Functional Materials, Namur Institute of Structured Matter, Université de Namur, Rue de Bruxelles, 61, Namur, 5000, Belgium
| | - Alexandra M Z Slawin
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
| | - Stuart Warriner
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - David Beljonne
- Laboratory for Chemistry of Novel Materials, University of Mons, Mons, 7000, Belgium
| | - Yoann Olivier
- Laboratory for Chemistry of Novel Materials, University of Mons, Mons, 7000, Belgium
- Laboratory for Computational Modeling of Functional Materials, Namur Institute of Structured Matter, Université de Namur, Rue de Bruxelles, 61, Namur, 5000, Belgium
| | - Ifor D W Samuel
- Organic Semiconductor Centre, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, KY16 9SS, UK
| | - Eli Zysman-Colman
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, KY16 9ST, UK
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43
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Huang Z, Xie H, Miao J, Wei Y, Zou Y, Hua T, Cao X, Yang C. Charge Transfer Excited State Promoted Multiple Resonance Delayed Fluorescence Emitter for High-Performance Narrowband Electroluminescence. J Am Chem Soc 2023. [PMID: 37276361 DOI: 10.1021/jacs.3c01267] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters are promising candidates for narrowband organic light-emitting diodes, but their electroluminescent performance is typically hindered by the slow reverse intersystem crossing rate (kRISC). Herein, we present an effective strategy to introduce a multichannel reverse intersystem crossing (RISC) pathway with large spin-orbit coupling by orthogonally linking an electron-donating unit to the MR framework. Through delicate manipulation of the excited-state energy levels, an additional intersegmental charge transfer triplet state could be "silently" induced without perturbing the MR character of the lowest excited singlet state. The proof-of-concept emitter CzBN3 not only affords 23-fold increase of kRISC compared with its prototypical MR skeleton but also realizes close-to-unity photoluminescence quantum yield, large radiative rate constant, and very narrow emission spectrum. These merits enable high maximum external quantum efficiency (EQEmax) of up to 37.1% and alleviated efficiency roll-off in the sensitizer-free device (EQE1000 = 30.4%), and a further boost of efficiency (EQEmax/1000 = 42.3/34.1%) is realized in the hyperfluorescent device. The state-of-the-art electroluminescent performance validates the superiority of our molecular design strategy.
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Affiliation(s)
- Zhongyan Huang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China
| | - Honghui Xie
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China
| | - Jingsheng Miao
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China
| | - Yaxiong Wei
- Anhui Province Key Laboratory of Optoelectric Materials Science and Technology, School of Physics and Electronic Information, Anhui Normal University, Wuhu 241000, China
| | - Yang Zou
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China
| | - Tao Hua
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China
| | - Xiaosong Cao
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China
| | - Chuluo Yang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen 518060, China
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44
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Zeng X, Wang L, Dai H, Huang T, Du M, Wang D, Zhang D, Duan L. Orbital Symmetry Engineering in Fused Polycyclic Heteroaromatics toward Extremely Narrowband Green Emissions with an FWHM of 13 nm. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2211316. [PMID: 36859744 DOI: 10.1002/adma.202211316] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 02/17/2023] [Indexed: 06/02/2023]
Abstract
Multiresonance (MR) molecules generally face spectral broadening issues with redshifted emissions. Thus, green emitters with full widths at half maximum (FWHMs) of <20 nm are rarely reported, despite being highly desired. Herein, by properly fusing indolo(3,2,1-jk)carbazole (ICZ) and naphthalene moieties, green MR emitters are reported, which have FWHMs of merely 13 nm (0.064 eV) and 14 nm (0.069 eV) in dichloromethane, accompanied by high photoluminescence quantum yields of >95%, which represent not only the smallest FWHMs among all green MR emitters but also the first green emitters based on ICZ MR derivatives. Theoretical studies reveal that the orbital interactions between the antisymmetric sites of the segments play an important role in extending the conjugation length in the fusion architectures while simultaneously maintaining a small FWHM. The corresponding organic light-emitting diodes exhibit green emission peaks at 508-509 nm and the first green electroluminescence FWHM of <20 nm ever reported. Benefiting from the preferential horizontal dipole orientation, a high maximum external quantum efficiency of up to 30.9% is obtained, which remains at 28.9% and 23.2% under luminances of 1000 and 10 000 cd m-2 , respectively, outperforming most reported green devices based on narrowband emitters.
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Affiliation(s)
- Xuan Zeng
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
- Laboratory of Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
| | - Lu Wang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Hengyi Dai
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Tianyu Huang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Mingxu Du
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Dong Wang
- Laboratory of Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
| | - Dongdong Zhang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Lian Duan
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
- Laboratory of Flexible Electronics Technology, Tsinghua University, Beijing, 100084, P. R. China
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45
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Chen SH, Chen ZH, Jiang K, Cao XY, Chen LY, Ouyang J, Wang ZY. Regulating donor-acceptor system toward highly efficient dual-state emission for sensitive response of nitroaromatic explosives. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 300:122905. [PMID: 37245375 DOI: 10.1016/j.saa.2023.122905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/15/2023] [Accepted: 05/19/2023] [Indexed: 05/30/2023]
Abstract
Dual-state emission luminogens (DSEgens) as fluorophores emit efficiently in solution and solid forms have gained increasing concern in the field of chemical sensing. Recent efforts by our group led to the identification of DSEgens as an easy-to-visualize nitroaromatic explosives (NAEs) detection platform. However, none of the previously studied NAEs probes show effective improvement in sensitivity. Here, we designed a series of benzoxazole-based DSEgens through multiple strategies driven by theoretical calculations, revealing their improved detecting performance on NAEs. Compounds 4a-4e exhibit thermal- and photo-stability, large Stokes shift as well as sensitivity solvatochromism (except for 4a and 4b). A subtle balance between rigid conjugation and distorted conformation endows these D-A type fluorophores 4a-4e with DSE properties. Furthermore, 4d and 4e show aggregation-induced emission phenomenon caused by distorted molecular conformation and restricted intramolecular rotation. Interestingly, DSEgen 4e displays anti-interference and sensitivity towards NAEs with a detection limit of 10-8 M. It can be applied for expedient and distinct visual identification of NAEs not only in solution but also on filter paper and film, supporting this new DSEgen as reliable NAEs chemoprobe.
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Affiliation(s)
- Si-Hong Chen
- School of Chemistry, South China Normal University, Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, GDMPA Key Laboratory for Process Control and Quality Evaluation of Chiral Pharmaceuticals, Guangzhou 510006, China
| | - Zhao-Hua Chen
- School of Chemistry, South China Normal University, Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, GDMPA Key Laboratory for Process Control and Quality Evaluation of Chiral Pharmaceuticals, Guangzhou 510006, China
| | - Kai Jiang
- Key Laboratory of Functional Molecular Engineering of Guangdong Province, South China University of Technology, Guangzhou 510640, China.
| | - Xi-Ying Cao
- School of Chemistry, South China Normal University, Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, GDMPA Key Laboratory for Process Control and Quality Evaluation of Chiral Pharmaceuticals, Guangzhou 510006, China
| | - Liu-Yu Chen
- School of Chemistry, South China Normal University, Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, GDMPA Key Laboratory for Process Control and Quality Evaluation of Chiral Pharmaceuticals, Guangzhou 510006, China
| | - Jin Ouyang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Zhao-Yang Wang
- School of Chemistry, South China Normal University, Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education, Guangzhou Key Laboratory of Analytical Chemistry for Biomedicine, GDMPA Key Laboratory for Process Control and Quality Evaluation of Chiral Pharmaceuticals, Guangzhou 510006, China; Key Laboratory of Functional Molecular Engineering of Guangdong Province, South China University of Technology, Guangzhou 510640, China.
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46
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Sano Y, Shintani T, Hayakawa M, Oda S, Kondo M, Matsushita T, Hatakeyama T. One-Shot Construction of BN-Embedded Heptadecacene Framework Exhibiting Ultra-narrowband Green Thermally Activated Delayed Fluorescence. J Am Chem Soc 2023; 145:11504-11511. [PMID: 37192399 DOI: 10.1021/jacs.3c02873] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
BN-embedded nonacene, tridecacene, and heptadecacene frameworks were constructed using one-shot quadruple, sextuple, and octuple borylation reactions, respectively. The key to success is the judicious choice of borylating reagents and long-chain alkyl-substituted carbazolyl groups as boron-trapping groups, which suppressed the decrease in HOMO energy and insolubilization associated with borylation. Based on the product yields, each electrophilic C-H borylation proceeded in >99% yield, which is the best efficiency reported so far for C-H borylation reactions. Owing to the multiple resonance effects of boron and nitrogen, the prepared acenes exhibited ultra-narrowband green thermally activated delayed fluorescence with full-width at half-maximum of 12-16 nm; moreover, their kRISC values were in the order of 105 s-1. We fabricated an organic light-emitting diode by employing the nonacene as an emitter, which exhibited high external quantum efficiency (EQE) of 28.7%. The device also showed a minimum efficiency roll-off with an EQE of 25.8% at 1000 cd m-2.
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Affiliation(s)
- Yusuke Sano
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Toshiki Shintani
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Masahiro Hayakawa
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Susumu Oda
- Department of Chemistry, Graduate School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337, Japan
| | - Masakazu Kondo
- JNC Corporation, 5-1, Goikaigan, Ichihara, Chiba 290-8551, Japan
| | | | - Takuji Hatakeyama
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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47
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Wang X, Wang L, Meng G, Zeng X, Zhang D, Duan L. Improving the stability and color purity of a BT.2020 blue multiresonance emitter by alleviating hydrogen repulsion. SCIENCE ADVANCES 2023; 9:eadh1434. [PMID: 37172084 PMCID: PMC10181185 DOI: 10.1126/sciadv.adh1434] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Stable deep blue multiresonance emitters with small full width at half maximum (FWHM) are attractive for wide color-gamut organic light-emitting diodes (OLEDs). However, the steric repulsion from the spatially close hydrogens would twist the multiresonance skeletons, causing spectral broadening and molecular instability issues. Here, we strategically introduce a mesitylboron locking unit into a carbazole-embedded multiresonance model emitter, alleviating the hydrogen repulsions and also strengthening the para-positioned weak carbon-nitrogen bond in anionic states. An emission peaking at 452 nm with an FWHM of merely 14 nm and nearly BT.2020 blue chromaticity coordinates are obtained in toluene, affording a high maximum external quantum efficiency of 33.9% in a sensitizing device. Moreover, an impressive LT97 (time to decay to 97% of the initial luminance) of 178 hours at a constant current density of 12 mA/cm2 was achieved in a stable device with a small y coordinate of 0.057, nearly 20 times longer than the model emitter with even a substantially red-shifted emission.
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Affiliation(s)
- Xiang Wang
- Key Laboratory of Organic Optoelectronics, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Lu Wang
- Key Laboratory of Organic Optoelectronics, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Guoyun Meng
- Key Laboratory of Organic Optoelectronics, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Xuan Zeng
- Key Laboratory of Organic Optoelectronics, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Dongdong Zhang
- Key Laboratory of Organic Optoelectronics, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Lian Duan
- Key Laboratory of Organic Optoelectronics, Department of Chemistry, Tsinghua University, Beijing 100084, China
- Center for Flexible Electronics Technology, Tsinghua University, Beijing 100084, China
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48
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Belousov GK, Vaitusionak AA, Vasilenko IV, Ghasemi M, Andruleviciene V, Ivanchanka A, Volyniuk D, Kim H, Grazulevicius JV, Kostjuk SV. Through-Space Charge-Transfer Thermally Activated Delayed Fluorescence Alternating Donor–Acceptor Copolymers for Nondoped Solution-Processable OLEDs. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c02582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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49
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Lei B, Huang Z, Li S, Liu J, Bin Z, You J. Medium-Ring Strategy Enables Multiple Resonance Emitters with Twisted Geometry and Fast Spin-Flip to Suppress Efficiency Roll-Off. Angew Chem Int Ed Engl 2023; 62:e202218405. [PMID: 36717355 DOI: 10.1002/anie.202218405] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/19/2023] [Accepted: 01/30/2023] [Indexed: 02/01/2023]
Abstract
Suppressing aggregation-caused quenching (ACQ) effect and reducing device efficiency roll-off are both crucial yet challenging for multi-resonance (MR) emitters. Herein, we put forward a medium-ring strategy to design efficient MR emitters that feature heptagonal tribenzo[b,d,f]azepine (TBA) donors. The highly twisted conformation enlarges the intermolecular distances between the MR-emitting cores, and thus suppresses ACQ effect. Meanwhile, the introduction of heptagonal donors enhances spin-orbital coupling, so as to accelerate reverse intersystem crossing (RISC) process. This medium-ring strategy gives rise to the first example of blue MR emitter that simultaneously possesses radiative decay rate as fast as 108 s-1 and RISC rate as fast as 106 s-1 . Accordingly, DTBA-B2N3 enables to assemble high-performance blue organic light-emitting diodes (OLEDs) with maximum external quantum efficiency (EQEmax ) of 30.9 % and alleviated efficiency roll-off (EQE1000 : 20.5 %).
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Affiliation(s)
- Bowen Lei
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Zhenmei Huang
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Songtao Li
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Junjie Liu
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Zhengyang Bin
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Jingsong You
- Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
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50
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Wang W, Li X, Qi Z, Ji B, Wang Z, Wang S, Xiao J. Synthesis, Crystal Analysis, and Physical Properties of Double [6]helicene-Containing Heteroarenes with Circularly Polarized Luminescence. Org Lett 2023; 25:1343-1347. [PMID: 36583556 DOI: 10.1021/acs.orglett.2c03786] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Two novel helical heteronanographenes bearing a [6]helicene unit (3a and 5a) have been synthesized, and their molecular structures are unambiguously determined via single-crystal X-ray diffraction analyses. Density functional theory calculations suggest that the as-prepared compounds have isomerization barriers of 29.02 kcal/mol for 3a and 34.07 kcal/mol for 5a, respectively. Optical enantiomers of 5a exhibit appealing chiroptical properties.
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Affiliation(s)
- Wei Wang
- College of Chemistry and Environmental Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P.R. China
| | - Xueqing Li
- College of Chemistry and Environmental Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P.R. China
| | - Zewei Qi
- College of Chemistry and Environmental Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P.R. China
| | - Bingliang Ji
- College of Chemistry and Environmental Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P.R. China
| | - Zenghao Wang
- College of Chemistry and Environmental Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P.R. China
| | - Sujuan Wang
- College of Chemistry and Environmental Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P.R. China
| | - Jinchong Xiao
- College of Chemistry and Environmental Science, Key Laboratory of Chemical Biology of Hebei Province, Hebei University, Baoding 071002, P.R. China
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