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Jayabharathi J, Thanikachalam V. Robust luminogens as cutting-edge tools for efficient light emission in recent decades. Phys Chem Chem Phys 2024; 26:13561-13605. [PMID: 38655772 DOI: 10.1039/d4cp00737a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Blue luminogens play a vital role in white lighting and potential metal-free fluorescent materials and their high-lying excited states contribute to harvesting triplet excitons in devices. However, in TADF-OLEDs (ΔEST < 0.1 eV), although T1 excitons transfer to S1via RISC with 100% IQE, the longer lifetime of blue TADF suffers from efficiency roll-off (RO). In this case, hybridized local and charge transfer (HLCT) materials have attracted significant interest in lighting owing to their 100% hot exciton harvesting and enhanced efficiency. Both academics and industrialists widely use the HLCT strategy to improve the efficiency of fluorescent organic light-emitting diodes (FOLEDs) by harvesting dark triplet excitons through the RISC process. Aggregation-induced emissive materials (AIEgens) possess tight packing in the aggregation state, and twisted AIEgens with HLCT behaviour have a shortened conjugation length, inducing blue emission and making them suitable candidates for OLED applications. TTA-OLEDs are used in commercial BOLEDs because of their moderate efficiency and reasonable operation lifetime. In this review, we discuss the devices based on TTA fluorophores, TADF fluorophores, HLCT fluorophores, AIEgens and HLCT-sensitized fluorophores (HLCT-SF), which break through the statistical limitations.
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Affiliation(s)
- Jayaraman Jayabharathi
- Department of Chemistry, Annamalai University, Annamalainagar, Tamilnadu-608 002, India.
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2
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Chaudhran PA, Sharma A. Progress in the Development of Imidazopyridine-Based Fluorescent Probes for Diverse Applications. Crit Rev Anal Chem 2022:1-18. [PMID: 36562726 DOI: 10.1080/10408347.2022.2158720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Different classes of Imidazopyridine i.e., Imidazo[1,2-a]pyridine, Imidazo[1,5-a] pyridine, Imidazo[4,5-b]pyridine, have shown versatile applications in various fields. In this review, we have concisely presented the usefulness of the fluorescent property of imidazopyridine in different fields such as imaging tools, optoelectronics, metal ion detection, etc. Fluorescence mechanisms such as excited state intramolecular proton transfer, photoinduced electron transfer, fluorescence resonance energy transfer, intramolecular charge transfer, etc. are incorporated in the designed fluorophore to make it for fluorescent applications. It has been widely employed for metal ion detection, where selective metal ion detection is possible with triazole-attached imidazopyridine, β-carboline imidazopyridine hybrid, quinoline conjugated imidazopyridine, and many more. Also, other popular applications involve organic light emitting diodes and cell imaging. This review shed a light on recent development in this area especially focusing on the optical properties of the molecules with their usage which would be helpful in designing application-based new imidazopyridine derivatives.
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Affiliation(s)
- Preeti AshokKumar Chaudhran
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli, Uttar Pradesh, India
| | - Abha Sharma
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli, Uttar Pradesh, India
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3
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Cui Y, Pu Y, Li Z, Liang B, Li C, Wang Y. Structures and Photoluminescence Properties of Bis(aromatic amino)‐Based Isomers with Biphenyl as Bridge. ChemistrySelect 2022. [DOI: 10.1002/slct.202201389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yuanyuan Cui
- State Key Laboratory of Supramolecular Structure and Materials College of Chemistry Jilin University Changchun 130012 China
| | - Yexuan Pu
- State Key Laboratory of Supramolecular Structure and Materials College of Chemistry Jilin University Changchun 130012 China
| | - Zhiqiang Li
- Jihua Hengye (Foshan) Electronic Materials Co. Ltd. Foshan 528200 China
| | - Baoyan Liang
- Jihua Hengye (Foshan) Electronic Materials Co. Ltd. Foshan 528200 China
| | - Chenglong Li
- State Key Laboratory of Supramolecular Structure and Materials College of Chemistry Jilin University Changchun 130012 China
- Jihua Hengye (Foshan) Electronic Materials Co. Ltd. Foshan 528200 China
| | - Yue Wang
- State Key Laboratory of Supramolecular Structure and Materials College of Chemistry Jilin University Changchun 130012 China
- Jihua Hengye (Foshan) Electronic Materials Co. Ltd. Foshan 528200 China
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Fang Y, Meng Y, Yuan C, Du C, Wang KP, Chen S, Hu ZQ. Efficient deep blue emission by 4-styrylbenzonitrile derivatives in solid state: Synthesis, aggregation induced emission characteristics and crystal structures. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 267:120575. [PMID: 34772634 DOI: 10.1016/j.saa.2021.120575] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 10/08/2021] [Accepted: 10/30/2021] [Indexed: 06/13/2023]
Abstract
Organic fluorescent molecules with π-conjugated system have shown great importance in numerous applications including bioimaging and optoelectronics. Planar aggregation-induced emissive (AIE) organic compounds with efficient solid-state luminescence are rarely developed and urgently needed in various applications. In this work, highly planar 4-styrylbenzonitrile derivatives have been synthesized. Most of these compounds show strong AIE properties with hundred-fold fluorescent enhancement. Moreover, these molecules are deep blue emissive in solid state, exhibiting good to excellent fluorescence quantum efficiency. The single crystal analysis shows that adjacent molecules could form special J-type aggregation. The intramolecular rotations are efficiently restricted by various noncovalent interactions. These molecular arrangements could be essential for the observed strong emission in aggregated and solid state. This work has paved a new path to efficient AIE-active organic emitters with highly planar conformations from 4-styrylbenzonitrile structure.
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Affiliation(s)
- Ying Fang
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China
| | - Yuanyuan Meng
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China
| | - Chunming Yuan
- College of Chemistry and Enviromental Science, YiLi Normal University, Yining 835000, PR China
| | - Chunhui Du
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China
| | - Kun-Peng Wang
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China
| | - Shaojin Chen
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
| | - Zhi-Qiang Hu
- State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
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5
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Phenanthroimidazole substituted imidazo[1,2-a]pyridine derivatives for deep-blue electroluminescence with CIEy ∼ 0.08. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2021.113600] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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6
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Tang SS, Yang GX, Zhu JJ, He X, Jian JX, Lu F, Tong QX. Multifunctional Materials Serving as Efficient Non-Doped Violet-Blue Emitters and Host Materials for Phosphorescence. Chemistry 2021; 27:9102-9111. [PMID: 33871880 DOI: 10.1002/chem.202100717] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Indexed: 11/10/2022]
Abstract
Efficient multifunctional materials acting as violet-blue emitters, as well as host materials for phosphorescent OLEDs, are crucial but rare due to demand that they should have high first singlet state (S1 ) energy and first triplet state (T1 ) energy simultaneously. In this study, two new violet-blue bipolar fluorophores, TPA-PI-SBF and SBF-PI-SBF, were designed and synthesized by introducing the hole transporting moiety triphenylamine (TPA) and spirobifluorene (SBF) unit that has high T1 into high deep blue emission quantum yield group phenanthroimidazole (PI). As the results, the non-doped OLEDs based on TPA-PI-SBF exhibited excellent EL performance with a maximum external quantum efficiency (EQEmax ) of 6.76 % and a violet-blue emission with Commission Internationale de L'Eclairage (CIE) of (0.152, 0.059). The device based on SBF-PI-SBF displayed EQEmax of 6.19 % with CIE of (0.159, 0.049), which nearly matches the CIE coordinates of the violet-blue emitters standard of (0.131, 0.046). These EL performances are comparable to the best reported non-doped deep or violet-blue emissive OLEDs with CIEy<0.06 in recent years. Additionally, the green, yellow and red phosphorescent OLEDs with TPA-PI-SBF and SBF-PI-SBF as host materials achieved a high EQEmax of about 20 % and low efficiency roll-off at the ultra-high luminance of 10 000 cd m-2 . These results provided a new construction strategy for designing high-performance violet-blue emitters, as well as efficient host materials for phosphorescent OLEDs.
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Affiliation(s)
- Shan-Shun Tang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P.R. China
| | - Guo-Xi Yang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P.R. China
| | - Jie-Ji Zhu
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P.R. China
| | - Xin He
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P.R. China
| | - Jing-Xin Jian
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P.R. China
| | - Feng Lu
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P.R. China
| | - Qing-Xiao Tong
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P.R. China
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Zheng XH, Zhao JW, Chen X, Cai R, Yang GX, Zhu JJ, Tang SS, Lin ZH, Tao SL, Tong QX. Imidazo[1,2-a]pyridine as an Electron Acceptor to Construct High-Performance Deep-Blue Organic Light-Emitting Diodes with Negligible Efficiency Roll-Off. Chemistry 2020; 26:8588-8596. [PMID: 32187750 DOI: 10.1002/chem.202000518] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/17/2020] [Indexed: 01/09/2023]
Abstract
Two novel bipolar deep-blue fluorescent emitters, IP-PPI and IP-DPPI, featuring different lengths of the phenyl bridge, were designed and synthesized, in which imidazo[1,2-a]pyridine (IP) and phenanthroimidazole (PI) were proposed as an electron acceptor and an electron donor, respectively. Both of them exhibit outstanding thermal stability and high emission quantum yields. All the devices based on these two materials showed negligible efficiency roll-off with increasing current density. Impressively, non-doped organic light-emitting diodes (OLEDs) based on IP-PPI and IP-DPPI exhibited external quantum efficiencies (EQEs) of 4.85 % and 4.74 % with CIE coordinates of (0.153, 0.097) and (0.154, 0.114) at 10000 cd m-2 , respectively. In addition, the 40 wt % IP-PPI doped device maintained a high EQE of 5.23 % with CIE coordinates of (0.154, 0.077) at 10000 cd m-2 . The doped device based on 20 wt % IP-DPPI exhibited a higher deep-blue electroluminescence (EL) performance with a maximum EQE of up to 6.13 % at CIE of (0.153, 0.078) and maintained an EQE of 5.07 % at 10000 cd m-2 . To the best of our knowledge, these performances are among the state-of-the art devices with CIEy ≤0.08 at a high brightness of 10000 cd m-2 . Furthermore, by doping a red phosphorescent dye Ir(MDQ)2 (MDQ=2-methyldibenzo[f,h]quinoxaline) into the IP-PPI and IP-DPPI hosts, high-performance red phosphorescent OLEDs with EQEs of 20.8 % and 19.1 % were achieved, respectively. This work may provide a new approach for designing highly efficient deep-blue emitters with negligible roll-off for OLED applications.
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Affiliation(s)
- Xu-Hui Zheng
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Jue-Wen Zhao
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China (UESTC), Chengdu, 610054, P. R. China
| | - Xiang Chen
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Ruoke Cai
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Guo-Xi Yang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Jie-Ji Zhu
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Shan-Shun Tang
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Zhi-Hong Lin
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
| | - Si-Lu Tao
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China (UESTC), Chengdu, 610054, P. R. China
| | - Qing-Xiao Tong
- Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Material of Guangdong Province, Shantou University, Guangdong, 515063, P. R. China
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Li B, Song X, Jiang X, Li Z, Guo F, Wang Y, Zhao L, Zhang Y. Stable deep blue organic light emitting diodes with CIE of y < 0.10 based on quinazoline and carbazole units. CHINESE CHEM LETT 2020. [DOI: 10.1016/j.cclet.2019.06.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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9
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Lv X, Sun M, Xu L, Wang R, Zhou H, Pan Y, Zhang S, Sun Q, Xue S, Yang W. Highly efficient non-doped blue fluorescent OLEDs with low efficiency roll-off based on hybridized local and charge transfer excited state emitters. Chem Sci 2020; 11:5058-5065. [PMID: 34122963 PMCID: PMC8159223 DOI: 10.1039/d0sc01341b] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Designing a donor–acceptor (D–A) molecule with a hybridized local and charge transfer (HLCT) excited state is a very effective strategy for producing an organic light-emitting diode (OLED) with a high exciton utilization efficiency and external quantum efficiency. Herein, a novel twisting D–π–A fluorescent molecule (triphenylamine–anthracene–phenanthroimidazole; TPAAnPI) is designed and synthesized. The excited state properties of the TPAAnPI investigated through photophysical experiments and density functional theory (DFT) analysis reveal that its fluorescence is due to the HLCT excited state. The optimized non-doped blue OLED using TPAAnPI as a light-emitting layer exhibits a novel blue emission with an electroluminescence (EL) peak at 470 nm, corresponding to the Commission International de L'Eclairage (CIE) coordinates of (0.15, 0.22). A fabricated device termed Device II exhibits a maximum current efficiency of 18.09 cd A−1, power efficiency of 12.35 lm W−1, luminescence of ≈29 900 cd cm−2, and external quantum efficiency (EQE) of 11.47%, corresponding to a high exciton utilization efficiency of 91%. Its EQE remains as high as 9.70% at a luminescence of 1000 cd m−2 with a low efficiency roll-off of 15%. These results are among the best for HLCT blue-emitting materials involved in non-doped blue fluorescent OLEDs. The performance of Device II highlights a great industrial application potential for the TPAAnPI molecule. A new pure fluorescent blue HLCT-emitter was designed and synthesized. Highly efficient non-doped blue OLEDs with low efficiency roll-off were achieved.![]()
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Affiliation(s)
- Xianhao Lv
- Key Laboratory of Rubber-Plastics of the Ministry of Education/Shandong Province (QUST), School of Polymer Science & Engineering, Qingdao University of Science &Technology 53-Zhengzhou Road Qingdao 266042 P. R. China
| | - Mizhen Sun
- Key Laboratory of Rubber-Plastics of the Ministry of Education/Shandong Province (QUST), School of Polymer Science & Engineering, Qingdao University of Science &Technology 53-Zhengzhou Road Qingdao 266042 P. R. China
| | - Lei Xu
- Key Laboratory of Rubber-Plastics of the Ministry of Education/Shandong Province (QUST), School of Polymer Science & Engineering, Qingdao University of Science &Technology 53-Zhengzhou Road Qingdao 266042 P. R. China
| | - Runzhe Wang
- Key Laboratory of Rubber-Plastics of the Ministry of Education/Shandong Province (QUST), School of Polymer Science & Engineering, Qingdao University of Science &Technology 53-Zhengzhou Road Qingdao 266042 P. R. China
| | - Huayi Zhou
- Key Laboratory of Rubber-Plastics of the Ministry of Education/Shandong Province (QUST), School of Polymer Science & Engineering, Qingdao University of Science &Technology 53-Zhengzhou Road Qingdao 266042 P. R. China
| | - Yuyu Pan
- School of Petrochemical Engineering, Shenyang University of Technology 30 Guanghua Street Liaoyang 111003 P. R. China
| | - Shitong Zhang
- State Key Laboratory of Supramolecular Structure and Materials, Jilin University Changchun 130012 P. R. China
| | - Qikun Sun
- Key Laboratory of Rubber-Plastics of the Ministry of Education/Shandong Province (QUST), School of Polymer Science & Engineering, Qingdao University of Science &Technology 53-Zhengzhou Road Qingdao 266042 P. R. China
| | - Shanfeng Xue
- Key Laboratory of Rubber-Plastics of the Ministry of Education/Shandong Province (QUST), School of Polymer Science & Engineering, Qingdao University of Science &Technology 53-Zhengzhou Road Qingdao 266042 P. R. China
| | - Wenjun Yang
- Key Laboratory of Rubber-Plastics of the Ministry of Education/Shandong Province (QUST), School of Polymer Science & Engineering, Qingdao University of Science &Technology 53-Zhengzhou Road Qingdao 266042 P. R. China
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He X, Ren S, Liu H, Zhao S, Liu F, Du C, Min J, Zhang H, Lu P. Efficient Nondoped Pure Blue Organic Light‐Emitting Diodes Based on an Anthracene and 9,9‐Diphenyl‐9,10‐dihydroacridine Derivative. Chem Asian J 2019; 15:163-168. [DOI: 10.1002/asia.201901376] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2019] [Revised: 10/29/2019] [Indexed: 11/07/2022]
Affiliation(s)
- Xin He
- State Key Laboratory of Supramolecular Structure and MaterialsJilin University Qianjin Avenue Changchun 130012 P. R. China
| | - Shenghong Ren
- State Key Laboratory of Supramolecular Structure and MaterialsJilin University Qianjin Avenue Changchun 130012 P. R. China
| | - Hui Liu
- State Key Laboratory of Supramolecular Structure and MaterialsJilin University Qianjin Avenue Changchun 130012 P. R. China
| | - Shiyuan Zhao
- State Key Laboratory of Metastable Materials Science and TechnologyYanshan University Qinhuangdao 066004 P. R. China
| | - Futong Liu
- State Key Laboratory of Supramolecular Structure and MaterialsJilin University Qianjin Avenue Changchun 130012 P. R. China
| | - Chunya Du
- State Key Laboratory of Supramolecular Structure and MaterialsJilin University Qianjin Avenue Changchun 130012 P. R. China
| | - Jiarui Min
- State Key Laboratory of Metastable Materials Science and TechnologyYanshan University Qinhuangdao 066004 P. R. China
| | - Haiquan Zhang
- State Key Laboratory of Metastable Materials Science and TechnologyYanshan University Qinhuangdao 066004 P. R. China
| | - Ping Lu
- State Key Laboratory of Supramolecular Structure and MaterialsJilin University Qianjin Avenue Changchun 130012 P. R. China
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Xu Y, Wang C, Zhou X, Zhou J, Guo X, Liang X, Hu D, Li F, Ma D, Ma Y. Fine Modulation of the Higher-Order Excitonic States toward More Efficient Conversion from Upper-Level Triplet to Singlet. J Phys Chem Lett 2019; 10:6878-6884. [PMID: 31612720 DOI: 10.1021/acs.jpclett.9b02751] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Hot exciton luminogens capable of harvesting nonemissive triplet excitons via reverse intersystem crossing from high-order triplet (hRISC) to singlet have great potential in high-efficiency fluorescent organic light-emitting diodes (OLEDs). Although spin-orbit coupling (SOC) is regarded as a key factor affecting the RISC process, its effects on hot exciton materials are poorly understood. Herein, we design and synthesize two blue-emitting hot exciton luminogens, PABP and PAIDO, to study this issue by modulating the excited-state properties. Theoretical and experimental research contributions demonstrate that a stronger SOC between energetically close S1 (π-π*) and Tn (T3, n-π*) of PAIDO gives rise to faster and more efficient hRISC in comparison to that of PABP, leading to a higher external quantum efficiency and a higher exciton utilization efficiency. Crucially, the experimentally measured hRISC rate (khRISC) of hot exciton materials is on the order of 107 s-1, which is much faster than that of the thermally activated delayed fluorescence materials.
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Affiliation(s)
- Yuwei Xu
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P.R. China
| | - Cong Wang
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P.R. China
| | - Xuehong Zhou
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P.R. China
| | - Jiadong Zhou
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P.R. China
| | - Xiaomin Guo
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P.R. China
| | - Xiaoming Liang
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P.R. China
| | - Dehua Hu
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P.R. China
| | - Feng Li
- State Key Laboratory of Supramolecular Structure and Materials , Jilin University , 2699 Qianjin Avenue , Changchun 130012 , P.R. China
| | - Dongge Ma
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P.R. China
| | - Yuguang Ma
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P.R. China
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12
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Xu Y, Liang X, Liang Y, Guo X, Hanif M, Zhou J, Zhou X, Wang C, Yao J, Zhao R, Hu D, Qiao X, Ma D, Ma Y. Efficient Deep-Blue Fluorescent OLEDs with a High Exciton Utilization Efficiency from a Fully Twisted Phenanthroimidazole-Anthracene Emitter. ACS APPLIED MATERIALS & INTERFACES 2019; 11:31139-31146. [PMID: 31368304 DOI: 10.1021/acsami.9b10823] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A novel, efficient, deep-blue fluorescent emitter mPAC, with a meta-connected donor-acceptor structure containing phenanthroimidazole (PPI) as the donor and phenylcarbazole-substituted anthracene (An-CzP) as the acceptor, was designed and synthesized. The meta-linkage provided a highly twisted molecular conformation, which efficiently interrupts the intramolecular π-conjugation, resulting in a deep-blue emission. The optimized nondoped device based on mPAC displayed a deep-blue emission with a narrow full width at half-maximum of 56 nm and Commission Internationale de L'Eclairage coordinates of (0.16, 0.09). The maximum external quantum efficiency (EQEmax) is 6.76%, corresponding to a high exciton utilization efficiency (EUE) of 59.3-88.9%. Experimental results and theoretical analysis indicated that the high EUE is mainly ascribed to the reverse intersystem crossing (RISC) from T2 to S1, a "hot exciton" path in which the large T2-T1 energy gap (1.45 eV) and small T2-S1 energy difference (0.18 eV, T2 > S1) hamper the internal crossing from T2 to T1 and facilitate the RISC process. For the hot exciton path, the T2 state can be feasibly arranged to a high energy level, forming a thermal equilibrium with S1, even slightly higher than the deep-blue S1 to realize an exergonic RISC process, which is usually difficult for the thermally activated delayed fluorescence emitters.
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Affiliation(s)
- Yuwei Xu
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Xiaoming Liang
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Yiqian Liang
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Xiaomin Guo
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Muddasir Hanif
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Jiadong Zhou
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Xuehong Zhou
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Cong Wang
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Jingwen Yao
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Ruiyang Zhao
- College of Chemical Engineering , Qingdao University of Science and Technology , Qingdao 266042 , P. R. China
| | - Dehua Hu
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Xianfeng Qiao
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Dongge Ma
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
| | - Yuguang Ma
- Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , P. R. China
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Liang B, Wang J, Cheng Z, Wei J, Wang Y. Exciplex-Based Electroluminescence: Over 21% External Quantum Efficiency and Approaching 100 lm/W Power Efficiency. J Phys Chem Lett 2019; 10:2811-2816. [PMID: 31082247 DOI: 10.1021/acs.jpclett.9b01140] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Benzimidazole-triazine-based electron acceptor PIM-TRZ with high triplet exited-state energy and strong electron-transport ability was newly developed. A series of highly efficient exciplex emitters have been fabricated. The TAPC:PIM-TRZ (TAPC: di-[4-( N, N-ditoly amino)-phenyl]cyclohexane) film shows a high photoluminescence (PL) quantum yields (PLQY, Φf) of 93.4%, and the device based on TAPC:PIM-TRZ exhibits a low turn-on voltage of 2.3 V, high maximum efficiency of 71.2 cd A-1 (current efficiency, CE), 97.3 lm W-1 (power efficiency, PE), and 21.7% (external quantum efficiency, EQE), as well as a high EQE of 16.2% at a luminance of 5000 cd m-2. The device displays the highest efficiency among reported organic light-emitting devices with an exciplex film as the emitting layer. Furthermore, a green device is also fabricated with a TAPC:PIM-TRZ cohost using C545T (C545T: (10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1 H,5 H,11 H-benzopyrano[6,7-8- I, j]quinolizin-11-one)) as the dopant, and the highest CE, PE, and EQE are 68.3 cd A-1, 86.6 lm W-1, and 20.2%, respectively.
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Affiliation(s)
- Baoyan Liang
- State Key Laboratory of Supramolecular Structure and Materials , Jilin University , Changchun 130012 , People's Republic of China
| | - Jiaxuan Wang
- State Key Laboratory of Supramolecular Structure and Materials , Jilin University , Changchun 130012 , People's Republic of China
| | - Zong Cheng
- State Key Laboratory of Supramolecular Structure and Materials , Jilin University , Changchun 130012 , People's Republic of China
| | - Jinbei Wei
- State Key Laboratory of Supramolecular Structure and Materials , Jilin University , Changchun 130012 , People's Republic of China
| | - Yue Wang
- State Key Laboratory of Supramolecular Structure and Materials , Jilin University , Changchun 130012 , People's Republic of China
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