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Siddiqui I, Kumar S, Tsai YF, Gautam P, Shahnawaz, Kesavan K, Lin JT, Khai L, Chou KH, Choudhury A, Grigalevicius S, Jou JH. Status and Challenges of Blue OLEDs: A Review. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2521. [PMID: 37764550 PMCID: PMC10536903 DOI: 10.3390/nano13182521] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/04/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023]
Abstract
Organic light-emitting diodes (OLEDs) have outperformed conventional display technologies in smartphones, smartwatches, tablets, and televisions while gradually growing to cover a sizable fraction of the solid-state lighting industry. Blue emission is a crucial chromatic component for realizing high-quality red, green, blue, and yellow (RGBY) and RGB white display technologies and solid-state lighting sources. For consumer products with desirable lifetimes and efficiency, deep blue emissions with much higher power efficiency and operation time are necessary prerequisites. This article reviews over 700 papers covering various factors, namely, the crucial role of blue emission for full-color displays and solid-state lighting, the performance status of blue OLEDs, and the systematic development of fluorescent, phosphorescent, and thermally activated delayed fluorescence blue emitters. In addition, various challenges concerning deep blue efficiency, lifetime, and approaches to realizing deeper blue emission and higher efficacy for blue OLED devices are also described.
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Affiliation(s)
- Iram Siddiqui
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Sudhir Kumar
- Institute for Chemical and Bioengineering, ETH Zürich, 8093 Zürich, Switzerland
| | - Yi-Fang Tsai
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Prakalp Gautam
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Shahnawaz
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Kiran Kesavan
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Jin-Ting Lin
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Luke Khai
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Kuo-Hsien Chou
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Abhijeet Choudhury
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Saulius Grigalevicius
- Department of Polymer Chemistry and Technology, Kaunas University of Technology, LT-50254 Kaunas, Lithuania
| | - Jwo-Huei Jou
- Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan
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Meng QY, Wang R, Wang YL, Guo XW, Liu YQ, Wen XL, Yao CY, Qiao J. Longevity gene responsible for robust blue organic materials employing thermally activated delayed fluorescence. Nat Commun 2023; 14:3927. [PMID: 37400475 DOI: 10.1038/s41467-023-39697-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Accepted: 06/23/2023] [Indexed: 07/05/2023] Open
Abstract
The 3rd-Gen OLED materials employing thermally-activated delayed fluorescence (TADF) combine advantages of first two for high-efficiency and low-cost devices. Though urgently needed, blue TADF emitters have not met stability requirement for applications. It is essential to elucidate the degradation mechanism and identify the tailored descriptor for material stability and device lifetime. Here, via in-material chemistry, we demonstrate chemical degradation of TADF materials involves critical role of bond cleavage at triplet state rather than singlet, and disclose the difference between bond dissociation energy of fragile bonds and first triplet state energy (BDE-ET1) is linearly correlated with logarithm of reported device lifetime for various blue TADF emitters. This significant quantitative correlation strongly reveals the degradation mechanism of TADF materials have general characteristic in essence and BDE-ET1 could be the shared "longevity gene". Our findings provide a critical molecular descriptor for high-throughput-virtual-screening and rational design to unlock the full potential of TADF materials and devices.
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Affiliation(s)
- Qing-Yu Meng
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, China
| | - Rui Wang
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, China
| | - Yi-Lei Wang
- Department of Chemistry, Tsinghua University, Beijing, China
| | - Xing-Wei Guo
- Department of Chemistry, Tsinghua University, Beijing, China
- Center of Basic Molecular Science, Department of Chemistry, Tsinghua University, Beijing, China
| | - Yu-Qi Liu
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, China
| | - Xue-Liang Wen
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, China
| | - Cheng-Yu Yao
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, China
| | - Juan Qiao
- Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, China.
- Laboratory for Flexible Electronics Technology, Tsinghua University, Beijing, China.
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3
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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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4
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Fu Y, Liu H, Tang BZ, Zhao Z. Realizing efficient blue and deep-blue delayed fluorescence materials with record-beating electroluminescence efficiencies of 43.4. Nat Commun 2023; 14:2019. [PMID: 37037820 PMCID: PMC10086064 DOI: 10.1038/s41467-023-37687-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 03/28/2023] [Indexed: 04/12/2023] Open
Abstract
As promising luminescent materials for organic light-emitting diodes (OLEDs), thermally activated delayed fluorescence materials are booming vigorously in recent years, but robust blue ones still remain challenging. Herein, we report three highly efficient blue and deep-blue delayed fluorescence materials comprised of a weak electron acceptor chromeno[3,2-c]carbazol-8(5H)-one with a rigid polycyclic structure and a weak electron donor spiro[acridine-9,9'-xanthene]. They hold distinguished merits of excellent photoluminescence quantum yields (99%), ultrahigh horizontal transition dipole ratios (93.6%), and fast radiative transition and reverse intersystem crossing, which furnish superb blue and deep-blue electroluminescence with Commission Internationale de I'Eclairage coordinates (CIEx,y) of (0.14, 0.18) and (0.14, 0.15) and record-beating external quantum efficiencies (ηexts) of 43.4% and 41.3%, respectively. Their efficiency roll-offs are successfully reduced by suppressing triplet-triplet and singlet-singlet annihilations. Moreover, high-performance deep-blue and green hyperfluorescence OLEDs are achieved by utilizing these materials as sensitizers for multi-resonance delayed fluorescence dopants, providing state-of-the-art ηexts of 32.5% (CIEx,y = 0.14, 0.10) and 37.6% (CIEx,y = 0.32, 0.64), respectively, as well as greatly advanced operational lifetimes. These splendid results can surely inspire the development of blue and deep-blue luminescent materials and devices.
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Affiliation(s)
- Yan Fu
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology, Guangzhou, 510640, China
| | - Hao Liu
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology, Guangzhou, 510640, China
| | - Ben Zhong Tang
- School of Science and Engineering, Shenzhen Institute of Aggregate Science and Technology, The Chinese University of Hong Kong, Shenzhen, Guangdong, 518172, China
| | - Zujin Zhao
- State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology, Guangzhou, 510640, China.
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5
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Liu T, Deng C, Duan K, Tsuboi T, Niu S, Wang D, Zhang Q. Zero-Zero Energy-Dominated Degradation in Blue Organic Light-Emitting Diodes Employing Thermally Activated Delayed Fluorescence. ACS APPLIED MATERIALS & INTERFACES 2022; 14:22332-22340. [PMID: 35511443 DOI: 10.1021/acsami.2c02623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Blue-emitting organic light-emitting diodes (OLEDs) fall significantly behind other OLEDs in operational stability. To better understand the key factors governing the stability of blue OLEDs employing thermally activated delayed fluorescence (TADF), nine efficient sky-blue to green TADF emitters with different frontier orbital energy levels and different TADF lifetimes have been designed and synthesized on the basis of charge-transfer (CT) acridine/phenyltriazine derivatives. Among them, ToDMAC-TRZ, a molecule composed of a 9,9-dimethyl-2,7-di-o-tolyl-9,10-dihydroacridine donor and a 2,4,6-triphenyl-1,3,5-triazine acceptor, shows a quantum yield of nearly 1 and a TADF lifetime as short as 0.59 μs in thin film. However, the stability of OLEDs is independent of the frontier orbital energy levels and TADF lifetime of the emitter. In contrast, the device half-life is found to decrease by five-sixths as the 0-0 energy of the singlet excitons increases by about 0.06 eV, which can be well-explained by the Arrhenius equation employing a photoreaction model. Whether in photoluminescence or electroluminescence, the contribution of long-lifetime triplet excitons to degradation is much lower than expected, which can be accounted for by how the solid-state solvation effect reduces the energy of the 3CT state and how most molecules have a low-lying locally excited triplet state.
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Affiliation(s)
- Tiangeng Liu
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Chao Deng
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Ke Duan
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Taiju Tsuboi
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Sheng Niu
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Dan Wang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Qisheng Zhang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China
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6
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Weng Y, Chen G, Nie J, Que S, Song SH, Yu Y, Zhang F, Liu H, Zhou X, Zhang Y, Sun J, Song JK, Wu C, Guo T, Yan Q. Hybrid Device of Blue GaN Light-Emitting Diodes and Organic Light-Emitting Diodes with Color Tunability for Smart Lighting Sources. ACS OMEGA 2022; 7:5502-5509. [PMID: 35187365 PMCID: PMC8851900 DOI: 10.1021/acsomega.1c06934] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
A lighting device with a wide color-tunable range is still a challenge for lighting based on either organic light-emitting diodes (OLEDs) or inorganic LEDs. In this work, we first proposed a novel hybrid device of organic LEDs and inorganic blue GaN LEDs to achieve full white and other colors. Organic LEDs were stacked with green and red emissive layers and connected with blue GaN LEDs in parallel but in opposite polarity voltage. Under the alternate-current (AC) driving, the hybrid structure can be controlled independently by applying timing variable opposite voltages to emit the light from either blue LEDs or the stacked OLEDs for forming mixed colors. The hybrid device can generate white light, varying in a wide range by changing the amplitude and duty ratio (DR) of AC-driving signals, from cold white to standard white and to warm white (3668-11 833 K). When an AC voltage of (4.80 V, -2.45 V) was applied, the device has a high color gamut of 95.24% National Television System Committee (NTSC) and a high color rendering index (R a) of 92.4%. The novel hybrid device with the blue LED and OLED in opposite polarity exhibits potential applications in smart solid-state lighting, display, and light communication.
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Affiliation(s)
- Yalian Weng
- College
of Physics and Information Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China
| | - Guixiong Chen
- College
of Physics and Information Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China
| | - Junyang Nie
- Faculty
of Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an 710049 China
| | - Sihua Que
- College
of Physics and Information Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China
| | - Suk-Ho Song
- Department
of Electrical and Computer Engineering, Sungkyunkwan University, Jangan-Gu, Suwon 16419, Gyeonggi-do, South Korea
| | - Yongshen Yu
- College
of Physics and Information Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China
| | - Fan Zhang
- Fujian
Prima Optoelectronics Company Ltd., Fuzhou 350000, Fujian, PR China
| | - Hengshan Liu
- Fujian
Prima Optoelectronics Company Ltd., Fuzhou 350000, Fujian, PR China
| | - Xiongtu Zhou
- College
of Physics and Information Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China
- Fujian
Science & Technology Innovation Laboratory for Optoelectronic
Information of China, Fuzhou 350116, Fujian, PR China
| | - Yongai Zhang
- College
of Physics and Information Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China
- Fujian
Science & Technology Innovation Laboratory for Optoelectronic
Information of China, Fuzhou 350116, Fujian, PR China
| | - Jie Sun
- College
of Physics and Information Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China
- Fujian
Science & Technology Innovation Laboratory for Optoelectronic
Information of China, Fuzhou 350116, Fujian, PR China
| | - Jang-Kun Song
- Department
of Electrical and Computer Engineering, Sungkyunkwan University, Jangan-Gu, Suwon 16419, Gyeonggi-do, South Korea
| | - Chaoxing Wu
- College
of Physics and Information Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China
- Fujian
Science & Technology Innovation Laboratory for Optoelectronic
Information of China, Fuzhou 350116, Fujian, PR China
| | - Tailiang Guo
- College
of Physics and Information Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China
- Fujian
Science & Technology Innovation Laboratory for Optoelectronic
Information of China, Fuzhou 350116, Fujian, PR China
| | - Qun Yan
- College
of Physics and Information Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China
- Fujian
Science & Technology Innovation Laboratory for Optoelectronic
Information of China, Fuzhou 350116, Fujian, PR China
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7
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Yin Y, Chen Z, Li RH, Yi F, Liang XC, Cheng SQ, Wang K, Sun Y, Liu Y. Highly Emissive Multipurpose Organoplatinum(II) Metallacycles with Contrasting Mechanoresponsive Features. Inorg Chem 2022; 61:2883-2891. [PMID: 35108490 DOI: 10.1021/acs.inorgchem.1c03563] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The development of supramolecular coordination complexes (SCCs) with a bright aggregate state or mechanical-stimuli-responsive luminescence is very significant and challenging. Herein, we report the synthesis of three different supramolecular platinum(II) metallacycles via coordination-driven self-assembly of a diplatinum(II) acceptor and organic donors with a triphenylamine, carbazole, or tetraphenylethylene moiety. The triphenylamine-modified SCC exhibits aggregation-induced emission enhancement (AIEE) but no mechanofluorochromism. The carbazole and tetraphenylethylene-based SCCs exhibit changes in aggregate fluorescence and also exhibit reversible mechanofluorochromism. This work not only reports three rare metallacycles with AIEE, aggregate fluorescence change, or mechanofluorochromic nature but also explores their potential applications in cell imaging and solid-state lighting.
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Affiliation(s)
- Ya Yin
- State Key Laboratory of Separation Membrane and Membrane Process, School of Chemistry, Tiangong University, Tianjin 300387, P. R. China.,Hubei Key Laboratory of Catalysis and Materials Science, College of Chemistry and Material Sciences, South-Central University for Nationalities, Wuhan 430074, P. R. China
| | - Zhao Chen
- Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang 330013, P. R. China
| | - Run-Hao Li
- Hubei Key Laboratory of Catalysis and Materials Science, College of Chemistry and Material Sciences, South-Central University for Nationalities, Wuhan 430074, P. R. China
| | - Fan Yi
- Hubei Key Laboratory of Catalysis and Materials Science, College of Chemistry and Material Sciences, South-Central University for Nationalities, Wuhan 430074, P. R. China
| | - Xiao-Cui Liang
- Hubei Key Laboratory of Catalysis and Materials Science, College of Chemistry and Material Sciences, South-Central University for Nationalities, Wuhan 430074, P. R. China
| | - Shi-Qi Cheng
- Hubei Key Laboratory of Catalysis and Materials Science, College of Chemistry and Material Sciences, South-Central University for Nationalities, Wuhan 430074, P. R. China
| | - Kai Wang
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, P. R. China
| | - Yue Sun
- State Key Laboratory of Separation Membrane and Membrane Process, School of Chemistry, Tiangong University, Tianjin 300387, P. R. China.,Hubei Key Laboratory of Catalysis and Materials Science, College of Chemistry and Material Sciences, South-Central University for Nationalities, Wuhan 430074, P. R. China
| | - Yi Liu
- State Key Laboratory of Separation Membrane and Membrane Process, School of Chemistry, Tiangong University, Tianjin 300387, P. R. China
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8
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Wang J, Zhang J, Jiang C, Yao C, Xi X. Effective Design Strategy for Aggregation-Induced Emission and Thermally Activated Delayed Fluorescence Emitters Achieving 18% External Quantum Efficiency Pure-Blue OLEDs with Extremely Low Roll-Off. ACS APPLIED MATERIALS & INTERFACES 2021; 13:57713-57724. [PMID: 34813274 DOI: 10.1021/acsami.1c17449] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
High-color purity organic emitters with a simultaneous combination of aggregation-induced emission (AIE) and thermally activated delayed fluorescence (TADF) characteristics are in great demand due to their excellent comprehensive performances toward efficient organic light-emitting diodes (OLEDs). In this work, two D-π-A-structure emitters, ICz-DPS and ICz-BP, exhibiting AIE and TADF properties were developed, and both the emitters have narrow singlet (S1)-triplet (T1) splitting (ΔEST) and excellent photoluminescence (PL) quantum yields (ΦPL), derived from the distorted configurations and weak intra/intermolecular interactions, suppressing exciton annihilation and concentration quenching. Their doped OLEDs based on ICz-BP provide an excellent electroluminescence external quantum efficiency (ηext) and current efficiency (ηC) of 17.7% and 44.8 cd A-1, respectively, with an ηext roll-off of 2.9%. Their nondoped OLEDs based on ICz-DPS afford high efficiencies of 11.7% and 30.1 cd A-1, with pure-blue emission with Commission Internationale de l'Éclairage (CIE) coordinates of (0.15, 0.08) and a low roll-off of 6.0%. This work also shows a strategy for designing AIE-TADF molecules by rational use of steric hindrance and weak inter/intramolecular interactions to realize high ΦPL values, fast reverse intersystem crossing process, and reduced nonradiative transition process properties, which may open the way toward highly efficient and small-efficiency roll-off devices.
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Affiliation(s)
- Jinshan Wang
- School of Materials Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, China
| | - Jianfeng Zhang
- School of Physics and Optoelectronic Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Cuifeng Jiang
- School of Materials Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, China
| | - Chuang Yao
- Chongqing Key Laboratory of Extraordinary Bond Engineering and Advance Materials Technology (EBEAM), Yangtze Normal University, Chongqing 408100, China
| | - Xinguo Xi
- School of Materials Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, China
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9
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Kim H, Lee Y, Lee H, Hong JI, Lee D. Click-To-Twist Strategy To Build Blue-to-Green Emitters: Bulky Triazoles for Electronically Tunable and Thermally Activated Delayed Fluorescence. ACS APPLIED MATERIALS & INTERFACES 2021; 13:12286-12295. [PMID: 33661594 DOI: 10.1021/acsami.1c00278] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Discovery of a new chemical moiety is the foundation to build new functional materials. For charge-transfer-type thermally activated delayed fluorescence (TADF) emitters, donor, acceptor, and π-spacer are the three key structural components. We invented a "click-to-twist" strategy to prepare a triazole-based acceptor unit that allows for a systematic modulation of the electronic and steric properties to control the excited-state photophysics. Taking the modular approach, six different emitters were prepared by varying the donor strength and π-spacer sterics for mix-and-match. These materials display deep blue to sky blue emissions in solutions, as well as apparent TADF characteristics in doped films. Organic light emitting diodes fabricated with these new TADF materials exhibit high external quantum efficiencies of up to 20.7% and maximum luminance of 6823 cd m-2. Building upon an intuitive and operationally straightforward method to build sterically congested molecules, this work showcases a new strategy to diversify TADF emitters by a mechanism-based design and modular synthesis.
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Affiliation(s)
- Hongsik Kim
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Youngnam Lee
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Hyeonho Lee
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Jong-In Hong
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
| | - Dongwhan Lee
- Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea
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10
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Liu X, Chan CY, Mathevet F, Mamada M, Tsuchiya Y, Lee YT, Nakanotani H, Kobayashi S, Shiochi M, Adachi C. Isotope Effect of Host Material on Device Stability of Thermally Activated Delayed Fluorescence Organic Light‐Emitting Diodes. SMALL SCIENCE 2021. [DOI: 10.1002/smsc.202000057] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Xuelong Liu
- Center for Organic Photonics and Electronics Research (OPERA) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
| | - Chin-Yiu Chan
- Center for Organic Photonics and Electronics Research (OPERA) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
| | - Fabrice Mathevet
- Center for Organic Photonics and Electronics Research (OPERA) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
- Institut Parisien de Chimie Moléculaire CNRS UMR 8232 Chimie des Polymères Sorbonne Université 4 place Jussieu 75005 Paris France
| | - Masashi Mamada
- Center for Organic Photonics and Electronics Research (OPERA) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
| | - Youichi Tsuchiya
- Center for Organic Photonics and Electronics Research (OPERA) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
| | - Yi-Ting Lee
- Center for Organic Photonics and Electronics Research (OPERA) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
| | - Hajime Nakanotani
- Center for Organic Photonics and Electronics Research (OPERA) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
- International Institute for Carbon Neutral Energy Research (WPI-I2CNER) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
| | - Shinichiro Kobayashi
- Fukuoka i3-Center for Organic Photonics and Electronics Research (i3-opera) 5-14 Kyudai-shinmachi, Nishi-ku Fukuoka 819-0388 Japan
| | - Masayuki Shiochi
- Fukuoka i3-Center for Organic Photonics and Electronics Research (i3-opera) 5-14 Kyudai-shinmachi, Nishi-ku Fukuoka 819-0388 Japan
| | - Chihaya Adachi
- Center for Organic Photonics and Electronics Research (OPERA) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
- International Institute for Carbon Neutral Energy Research (WPI-I2CNER) Kyushu University 744 Motooka, Nishi Fukuoka 819-0395 Japan
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