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Wu L, Liu C, Liu D, Li D, Li W, Zhang J, Mu X, Xin Z, Liu B, Qi H, Wang Z, Liu D, Su SJ, Zhou Y, Wu S, Ge Z. Spiro Units Embedded in the B/N Center for Constructing Highly Efficient Multiple Resonance TADF Emitters. Angew Chem Int Ed Engl 2025; 64:e202504723. [PMID: 40114623 DOI: 10.1002/anie.202504723] [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: 02/26/2025] [Revised: 03/20/2025] [Accepted: 03/21/2025] [Indexed: 03/22/2025]
Abstract
Departing from conventional molecular design strategies that rely on spiro units merely as peripheral components (side chains, terminal groups, or linkage units), we fully or partially incorporate the rigid 9,9'-spirobi[fluorene] (SF) unit into the boron/nitrogen multiple resonances (B/N-MR) emitting core, thereby successfully developing a series of proof-of-concept isomerized multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters, namely SF-BN1, SF-BN2, SF-BN3, and SF-BN4. Remarkably, these novel emitters exhibit exceptionally narrow full-width at half-maximum (FWHM) values of 15-21 nm in dilute toluene solutions and high photoluminescence quantum yields (PLQYs) of up to 90% in doped films. The corresponding organic light-emitting diode (OLED) based on SF-BN1 achieved high external quantum efficiency (EQE) of up to 29.0%, with CIE coordinates of (0.13, 0.08), closely aligning with the BT.2020 blue emission standard. Sky-blue OLEDs based on SF-BN3 can achieve a high EQE of 29.8%, with a narrow FWHM value of 18 nm; the hyperfluorescent (HF) OLEDs based on SF-BN3 improved the EQE of 35.5%. Moreover, we elucidated subtle variations in the connectivity of chemical functional groups within emitters and the polar environment and doping concentrations of OLEDs, which can significantly impact these isomers' optical and electroluminescent (EL) properties.
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Affiliation(s)
- Lin Wu
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, P.R. China
| | - Chunyu Liu
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, P.R. China
- Frontier Science Center for Smart Materials, College of Chemistry, Dalian University of Technology, 2 Linggong Road, Dalian, 116024, P.R. China
| | - Denghui Liu
- Frontier Science Center for Smart Materials, College of Chemistry, Dalian University of Technology, 2 Linggong Road, Dalian, 116024, P.R. China
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices, South China University of Technology, Wushan Road 381, Tianhe District, Guangzhou, Guangdong Province, 510640, P.R. China
| | - Deli Li
- Institute for Smart Materials & Engineering, University of Jinan, No. 336 Nanxinzhuang West Road, Jinan, 250022, P.R. China
| | - Wei Li
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, P.R. China
| | - Jiasen Zhang
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, P.R. China
| | - Xilin Mu
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, P.R. China
| | - Ziru Xin
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, P.R. China
| | - Bohong Liu
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, P.R. China
| | - Hengxuan Qi
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, P.R. China
| | | | - Di Liu
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
| | - Shi-Jian Su
- Frontier Science Center for Smart Materials, College of Chemistry, Dalian University of Technology, 2 Linggong Road, Dalian, 116024, P.R. China
| | - Yubo Zhou
- Ningbo Solartron Technology CO.,Ltd., Ningbo, 315000, China
| | - Siyao Wu
- Ningbo Solartron Technology CO.,Ltd., Ningbo, 315000, China
| | - Ziyi Ge
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, P.R. China
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Wang RJ, Wu YL, Li YK, Chen WC, Lian ZX, Zheng PY, Shen KJ, Zhou L, Wang Z, Liu XL, Bi H, Wang Y, Huo Y. Competitive Spatial Donor/Acceptor Interaction toward Efficient Blue Thermally Activated Delayed Fluorescence. ACS APPLIED MATERIALS & INTERFACES 2025. [PMID: 40390376 DOI: 10.1021/acsami.5c04911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2025]
Abstract
Through-space charge-transfer (TSCT) thermally activated delayed fluorescence (TADF) emitters show great promise for blue organic light-emitting diodes (OLEDs) but face challenges such as low efficiency and limited color purity. In this study, we designed and synthesized three asymmetric TSCT-TADF materials─CzTPT-PA, CzTPT-CIA, and CzTPT-IA─based on a dual donor/acceptor (D1/A/D2) architecture. The molecular design strategically leverages dominant donor-acceptor interactions and auxiliary coupling effects within a unique sandwich-like π-stacked structure, enabling precise control over excited-state properties. This design achieves blue-shifted emission while maintaining high photoluminescence quantum yields, addressing efficiency loss and concentration quenching through spatially confined interactions and locked molecular conformations. The resulting OLEDs exhibited blue electroluminescence with color coordinates of (0.16, 0.27), (0.15, 0.18), and (0.15, 0.09) for CzTPT-PA, CzTPT-CIA, and CzTPT-IA, respectively, alongside maximum external quantum efficiencies of 25.0%, 15.5%, and 9.9%. Notably, the CzTPT-IA-based device achieved deep-blue emission with high color purity, representing a significant advancement in the field. This work introduces an effective design strategy for TSCT-TADF emitters, paving the way for high-performance, blue OLEDs with enhanced efficiency and color precision.
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Affiliation(s)
- Ru-Jia Wang
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Yu-Lan Wu
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Yu-Kang Li
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
- Jihua Laboratory, 28 Huandao South Road, Foshan 528200, P. R. China
| | - Wen-Cheng Chen
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Zi-Xian Lian
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Pei-Yan Zheng
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Kai-Jun Shen
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Lu Zhou
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Zhiheng Wang
- Jihua Laboratory, 28 Huandao South Road, Foshan 528200, P. R. China
| | - Xiao-Long Liu
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
| | - Hai Bi
- Jihua Laboratory, 28 Huandao South Road, Foshan 528200, P. R. China
| | - Yue Wang
- Jihua Laboratory, 28 Huandao South Road, Foshan 528200, P. R. China
- State Key Laboratory of Supramolecular Structure and Materials College of Chemistry, Jilin University, Changchun 130012, P. R. China
| | - Yanping Huo
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, P. R. China
- Analytical & Testing Center, Guangdong University of Technology, Guangzhou 510006, P. R. China
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3
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Liu X, Hua L, Lai X, Kim JH, Zhu Q, Lee JY, Zhu W, Wang Y. High-Performance Solution Processable Red TADF-OLED with External Quantum Efficiency Exceeding 28% Using a Multi-Resonance Emitter Host. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2025; 37:e2500690. [PMID: 40190049 DOI: 10.1002/adma.202500690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2025] [Revised: 03/18/2025] [Indexed: 05/28/2025]
Abstract
Achieving high-efficiency soluble red thermally activated delayed fluorescence (TADF) emitters remains a substantial challenge owing to the constraints imposed by the energy-gap law. In this study, an asymmetric pyrene-azaacene derivative, named PBCNT, is prepared and characterized, featuring a strong electron-donating tert-butyl diphenylamine moiety and an electron-withdrawing cyano group. PBCNT exhibits intense red emission with a peak wavelength of 664 nm in a toluene solution. It demonstrates an evident TADF character in the solid state, attributed to a small energy difference of 0.04 eV between its lowest singlet and triplet states. By employing a multi resonance-type TADF molecule as the host matrix, a solution-processed organic light-emitting diode (OLED) based on PBCNT achieved a record-high maximum external quantum efficiency (EQE) of 28.5%, with a red emission peak at 608 nm, facilitated by effective Förster energy transfer, good horizontal emitting dipole orientation and managed intermolecular interactions between the host and dopant. This represents one of the highest EQE values reported among solution-processed red TADF OLEDs emitting electroluminescence at wavelengths greater than 600 nm. This paper introduces a promising pathway for developing efficient red TADF emitters that overcome the limitations of the energy-gap law.
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Affiliation(s)
- Xiaolong Liu
- School of Materials Science & Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Lei Hua
- School of Materials Science & Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Xiaoyi Lai
- School of Materials Science & Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Ji Hun Kim
- Department of Display Convergence Engineering, Sungkyunkwan University, Suwon, Gyeonggi, 16419, Republic of Korea
| | - Qinyu Zhu
- School of Materials Science & Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Jun Yeob Lee
- Department of Display Convergence Engineering, Sungkyunkwan University, Suwon, Gyeonggi, 16419, Republic of Korea
- SKKU Institute of Energy Science and Technology, Sungkyunkwan University, Suwon, Gyeonggi, 16419, Republic of Korea
- School of Chemical Engineering, Sungkyunkwan University, Suwon, Gyeonggi, 16419, Republic of Korea
| | - Weiguo Zhu
- School of Materials Science & Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Yafei Wang
- School of Materials Science & Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
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4
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Li Q, Zhao H, Li M, Liu Y, Yan S, Ren Z. Fused Dual-Donor Design for Accelerating Reverse Intersystem Crossing Rates of Spatially Folded Through-Space Charge Transfer Emitters. Angew Chem Int Ed Engl 2025:e202506654. [PMID: 40234192 DOI: 10.1002/anie.202506654] [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: 03/24/2025] [Revised: 04/15/2025] [Accepted: 04/15/2025] [Indexed: 04/17/2025]
Abstract
The development of through-space charge transfer (TSCT)-thermally activated delayed fluorescence (TADF) material is defective in relatively low reverse intersystem crossing (RISC) rates (commonly <5 × 105 s-1). Herein, we fuse two 3,6-dimethyl-8H-indolo[3,2,1-de]acridine (IAc) donor units to obtain large planar donors (m-bIAc and p-bIAc) for forming spatially folded A-D|D-A configured TSCT emitters (DCT-1 and DCT-2). The configuration of highly parallel and large-plane intramolecular multiple π-stacking has been achieved. The symmetrical multi-channel charge transfer networks of emitters induce multiple energetically proximal excited states within a small energy range (<0.12 eV) at the lowest excited state, creating additional configuration interaction and spin-orbit coupling channels to accelerate the RISC process. This molecular configuration yields enhanced RISC rates of 6.19 × 105 s-1 for DCT-1 and 1.05 × 106 s-1 for DCT-2. Solution-processed organic light-emitting diodes employing these emitters achieve maximum external quantum efficiencies of 18.9% (DCT-1, 474 nm sky-blue emission) and 23.9% (DCT-2, 498 nm green emission), with attenuated efficiency roll-offs of DCT-2 (12% at 1000 cd m-2). This work provides a critical pathway for manipulating dense excited states to address the bottleneck of the RISC rates while maintaining structural rigidity, promoting further advancement of TSCT-TADF materials.
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Affiliation(s)
- Quanwei Li
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China
| | - Haisong Zhao
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China
| | - Maoqiu Li
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China
| | - Yuchao Liu
- Key Laboratory of Rubber-Plastics, Ministry of Education, Qingdao University of Science & Technology, Qingdao, 266042, P.R. China
| | - Shouke Yan
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China
- Key Laboratory of Rubber-Plastics, Ministry of Education, Qingdao University of Science & Technology, Qingdao, 266042, P.R. China
| | - Zhongjie Ren
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P.R. China
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5
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Li Q, Zhao H, Zhao J, Cao Z, Yu C, Yan S, Ren Z. Enhancing electroluminescence performance of ultra-deep-blue through-space charge transfer emitters with CIE y ≈ 0.05 via methyl-modification. Chem Sci 2025; 16:6434-6442. [PMID: 40103726 PMCID: PMC11912506 DOI: 10.1039/d4sc08094g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2024] [Accepted: 03/08/2025] [Indexed: 03/20/2025] Open
Abstract
Achieving efficient solution-processed ultra-deep-blue OLEDs remains a challenge. Herein, a methyl-modification strategy is proposed to overcome weak intramolecular charge transfer and the large energy gap between the singlet and triplet states (ΔE ST) of ultra-deep-blue through-space charge transfer (TSCT)-thermally activated delayed fluorescence (TADF) emitters. In this way, the reverse intersystem crossing (RISC) process is found to be effective from T1 to S1 and can be accelerated with the assistance of T2. As a result, the ultra-deep-blue TSCT emitter 3MeCz-BO exhibits a minimized ΔE ST of 0.02 eV, and an enhanced RISC rate of 3.71 × 105 s-1. Additionally, this modification can improve the solubility, enabling the fabrication of solution-processed organic light-emitting diodes (OLEDs). The maximum external quantum efficiency of the 3MeCz-BO-based solution-processed OLED reaches 10.1%, with a Commission Internationale de L'Eclairage (CIE) coordinates of (0.151, 0.051) and a luminance of 1334 cd m-2. This work is the first instance of developing high-performance ultra-deep-blue solution-processed TSCT-TADF OLEDs, which show comparable performance to vacuum-deposited OLEDs. Furthermore, the 3MeCz-BO-based OLED fits well within the standard Red Green Blue (sRGB) of CIE coordinates (0.15, 0.06), and is close to the CIE coordinates (0.131, 0.046) for the Rec. 2020 standard, implying its potential application in colorful display devices.
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Affiliation(s)
- Quanwei Li
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology Beijing 100029 China
| | - Haisong Zhao
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology Beijing 100029 China
| | - Jinyang Zhao
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology Beijing 100029 China
| | - Zhongxu Cao
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology Beijing 100029 China
| | - Chao Yu
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology Beijing 100029 China
| | - Shouke Yan
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology Beijing 100029 China
- Department Key Laboratory of Rubber-Plastics Ministry of Education, School of Polymer Science and Engineering, Qingdao University of Science & Technology Qingdao 266042 China
| | - Zhongjie Ren
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology Beijing 100029 China
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Huang J, Feng H, Zhang L, Jie K. Forward- and Retro-Vapofluorochromism of Sponge-Like Macrocycle Crystals. Angew Chem Int Ed Engl 2025; 64:e202500022. [PMID: 39846797 DOI: 10.1002/anie.202500022] [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: 01/01/2025] [Revised: 01/23/2025] [Accepted: 01/23/2025] [Indexed: 01/24/2025]
Abstract
Achieving dynamic multicolor emission through solid-state molecular motion is of significant importance for advancing applications in organic solid-state luminescent materials. Herein, we report macrocycle crystals with unique forward- and retro-vapofluorochromic behavior, which is realized by reversible amine vapor uptake and amine-"squeeze" induced guest release. The forward-vapofluorochromism occurs when aliphatic amines penetrate guest-free macrocycle crystals to form host-guest complex crystals. These fluorescent properties can be reversibly toggled by exposing the amine-loaded crystals to another amine vapor through competitive guest replacement inside the crystals. Notably, retro-vapofluorochromism is achieved by exposing amine-loaded crystals to α-methylbenzylamine (MBA). Mechanistic studies show that MBA molecules do not penetrate the crystals, but rather "squeeze" the crystals to release loaded amines, driving the amine-loaded crystals back to the guest-free phase. The demonstrated forward- and retro-vapofluorochromism has already been successfully integrated into a highly secure five-layer information encryption system.
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Affiliation(s)
- Jingwei Huang
- State Key Laboratory of Coordination Chemistry, Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China
| | - Haohui Feng
- State Key Laboratory of Coordination Chemistry, Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China
| | - Linnan Zhang
- State Key Laboratory of Coordination Chemistry, Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China
| | - Kecheng Jie
- State Key Laboratory of Coordination Chemistry, Key Laboratory of Mesoscopic Chemistry of MOE, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P. R. China
- Jiangsu Key Laboratory of Advanced Organic Materials, Nanjing University, Nanjing, 210023, P. R. China
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7
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Meng X, Lang X, Cao Z. Structure Evolution of Organic Luminescent Molecules Utilizing Through-Space Charge Transfer Mechanism. Chem Asian J 2025; 20:e202401488. [PMID: 39996296 DOI: 10.1002/asia.202401488] [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: 10/27/2024] [Revised: 02/18/2025] [Accepted: 02/24/2025] [Indexed: 02/26/2025]
Abstract
Organic structures provide an extensive platform for luminescent materials thanks to the easy to design and synthesize, low toxicity and tunable functionalization. Through-space charge transfer (TSCT) in organic molecules, characterized by the transfer of excitons through spatial charge motion, has emerged as a significant research topic in optoelectronics, offering new avenues for the development of high-performance luminescent materials. This review systematically summarizes the fundamental principles of TSCT and highlights the recent advancements in organic small molecules that exhibit this emission mechanism. Key aspects covered include the molecular design strategies that enhance TSCT efficiencies, the role of charge transport spacers, and the correlation between molecular donor-acceptor structures and emission properties. Furthermore, the review addresses the challenges and future directions in the field, emphasizing the importance of understanding TSCT for the development of next-generation light-emitting materials. By providing a comprehensive analysis of current research, this review serves as a crucial resource for researchers and practitioners aiming to innovate in the realm of organic optoelectronic materials, ultimately contributing to a deeper understanding of TSCT processes and their practical applications.
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Affiliation(s)
- Xin Meng
- Shandong Key Laboratory of Life-Organic Analysis, and School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, Shandong, P. R. China
| | - Xuteng Lang
- Shandong Key Laboratory of Life-Organic Analysis, and School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, Shandong, P. R. China
| | - Ziping Cao
- Shandong Key Laboratory of Life-Organic Analysis, and School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, 273165, Shandong, P. R. China
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Wrigley L, Schlenker CW. Singlet-Triplet Inversion. Annu Rev Phys Chem 2025; 76:329-355. [PMID: 40258242 DOI: 10.1146/annurev-physchem-082423-120310] [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: 04/23/2025]
Abstract
The inversion of singlet and triplet states is a rare phenomenon, where, in opposition to Hund's first rule, singlet electronic states are stabilized relative to their triplet counterparts. The recent discovery of organic molecules exhibiting this inversion presents exciting new technological opportunities, such as addressing stability issues in organic light-emitting diodes (OLEDs). In this review, we describe fundamental molecular properties that can yield singlet-triplet inversion, generally ascribed to a phenomenon known as dynamic spin polarization. We discuss the systems in which singlet-triplet inversion was theoretically proposed, experimentally verified, and first implemented in an OLED device. We highlight key insights from the extensive computational work being carried out to understand the intricacies of these systems. Finally, we consider the outlook for future inverted singlet-triplet (IST) emitters.
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Affiliation(s)
- Liam Wrigley
- Department of Chemistry, University of Washington, Seattle, Washington, USA;
| | - Cody W Schlenker
- Department of Chemistry, University of Washington, Seattle, Washington, USA;
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Liu RH, Li MT, Yang YJ, Ge SJ, Qu ZH, Feng ZQ, Wang Y, Yu ZH, Zhou DY, Zhong C, Liao LS, Jiang ZQ. Efficiency Boost in Through Space Charge Transfer Emitters: Insights from Spiro Lateral Rocking Confinement. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2025; 37:e2415951. [PMID: 39668480 DOI: 10.1002/adma.202415951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2024] [Revised: 11/25/2024] [Indexed: 12/14/2024]
Abstract
Intramolecular through-space charge-transfer (TSCT) excited states have emerged as promising candidates for thermally activated delayed fluorescence (TADF) emitters. This study addresses the challenges in tuning excited state dynamics through conformational engineering, which significantly impacts exciton utilization. An effective strategy is presented to enhance the performance of TSCT-TADF molecules by restricting the lateral rocking of the spiro unit via immobilizing groups, which indirectly adjusts the conformations of the donor and acceptor subunits. This approach is successfully illustrated with two TSCT-TADF emitters, 8PhDM-B and 8PyDM-B, featuring sterical aryl phenyl and pyridine substitutions at the C8 site of a rigid spiro-fluorene bridge. Organic light-emitting diodes (OLEDs) utilizing these emitters demonstrated impressive maximum external quantum efficiencies of 33.1% and 31.0%, respectively. The findings underscore the importance of the rocking confined strategy in refining excited state dynamics, thereby providing valuable insights for the design of highly efficient OLED emitters.
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Affiliation(s)
- Rui-Hong Liu
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Meng-Tian Li
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Yue-Jian Yang
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Shi-Jie Ge
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Zhi-Hao Qu
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Zi-Qi Feng
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Yu Wang
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Zhe-Hong Yu
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Dong-Ying Zhou
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Cheng Zhong
- Department of Chemistry, Hubei Key Laboratory on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan, 430072, China
| | - Liang-Sheng Liao
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
- Macao Institute of Materials Science and Engineering, Macau University of Science and Technology, Taipa, Macau, 999078, China
| | - Zuo-Quan Jiang
- Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu, 215123, China
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10
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Zhang J, Liu D, Li D, Sun K, Li W, Meng Y, Liu C, Wu Y, Fang K, Mu X, Liu C, Su SJ, Ge Z. Enhancing Carrier Behavior via Controlled Molecular Film Formation Engineering Leads to Significant Improvement in Electroluminescence. Angew Chem Int Ed Engl 2025; 64:e202415856. [PMID: 39286944 DOI: 10.1002/anie.202415856] [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: 08/19/2024] [Revised: 09/14/2024] [Accepted: 09/16/2024] [Indexed: 09/19/2024]
Abstract
The quality of organic thin films critically influences carrier dynamics in organic semiconductors. In neat/doped films, even tiny voids can be penetrated by water or oxygen molecules to create charge-trap states called water/oxygen-induced traps that significantly hinder carrier mobility. While the water/oxygen-induced traps in non-doped films and crystalline states have been investigated comprehensively, there is a lack of thorough examination regarding their properties in the doped state. Therefore, there is a high demand for a molecular design strategy that effectively modulates the molecular stacking behavior in doped films and practical devices and enhances the quality of these films. Herein, we proposed a versatile molecular design principle that enables the formation of "nano-cluster" structures on both the surface and interior of doped films in target molecule 10-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-1'-(4-fluorophenyl)-10H-spiro[acridine-9,9'-xanthene] (DspiroO-F-TRZ), which is modified with a fluorophenyl group. These "nano-cluster" structures exhibit more uniform shapes within doped films and effectively reduce defective state densities while enhancing carrier injection and transport properties, ultimately improving device performance. Notably, TADF-OLED based on DspiroO-F-TRZ demonstrates nearly twice as much efficiency as its control counterpart due to contributions from 'nano-cluster' structure enhancements toward improved electroluminescence performance.
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Affiliation(s)
- Jiasen Zhang
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Denghui Liu
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices>, South China University of Technology, Wushan Road 381, Tianhe District, Guangzhou, 510640, Guangdong Province, P.R. China
| | - Deli Li
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Kexuan Sun
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Wei Li
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Yuanyuan Meng
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Chang Liu
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Yujie Wu
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Kaibo Fang
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Xilin Mu
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Chunyu Liu
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Shi-Jian Su
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices>, South China University of Technology, Wushan Road 381, Tianhe District, Guangzhou, 510640, Guangdong Province, P.R. China
| | - Ziyi Ge
- Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P.R. China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
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11
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Yu J, Tang J, Ma Z, Wang H. Enhancing Reverse Intersystem Crossing in TSCT-TADF Emitters: Heavy Atom Modulation of Multiresonance Acceptors. J Phys Chem A 2025; 129:459-469. [PMID: 39752230 DOI: 10.1021/acs.jpca.4c06357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2025]
Abstract
With the rapid development of thermally activated delayed fluorescence (TADF) materials, achieving efficient reverse intersystem crossing (RISC) to mitigate triplet-triplet annihilation has emerged as a prominent research focus. This study investigates five derivative molecules, featuring varied bridging atoms/groups (O, S, Se, -CH2-), designed from the reported TADF molecule AC-BO with through-space charge transfer (TSCT) properties. Utilizing time-dependent density functional theory coupled with a PCM solution model, their excited state behaviors were simulated in a toluene environment. Interestingly, it was observed that RISC in AC-BO and one derivative, AC-BCO, occurs predominantly via the T2 state rather than the typical T1 state (3LEB, where B denotes the fluorene bridge), distinguishing it from conventional TSCT-TADF compounds, where RISC typically involves transitions between the 3CT and 1CT states. This distinctive mode is attributed to reduced spin-orbit coupling (SOC) between 1CT and 3LEB, with T2 representing a significant contributor to the RISC process through its 3CT character. Introduction of heavy atoms enhances the electron-withdrawing ability of the acceptor unit, leading to the T1 transitions exhibiting 3MRCT characteristics and increased SOC, thereby favoring RISC via 3MRCT to 1CT transitions. This study not only deepens our understanding of transition mechanisms in TSCT-TADF compounds but also provides crucial insights into the molecular design and regulation of excited triplet states.
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Affiliation(s)
- Jikai Yu
- Institute of Nanoscience and Engineering, Henan University, Kaifeng, Henan 475004, China
| | - Jia Tang
- Institute of Nanoscience and Engineering, Henan University, Kaifeng, Henan 475004, China
| | - Zhiying Ma
- Institute of Nanoscience and Engineering, Henan University, Kaifeng, Henan 475004, China
| | - Hua Wang
- Institute of Nanoscience and Engineering, Henan University, Kaifeng, Henan 475004, China
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12
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Wang S, Yang Z, Sun X, Wu M, Sheng K, Zhang L, Yang B, Wang K, Sui Y, Zou B. Anomalous Pressure-Induced Blue-Shifted Emission of Ionic Copper-Iodine Clusters: The Competitive Effect between Cuprophilic Interactions and Through-Space Interactions. Angew Chem Int Ed Engl 2025; 64:e202414810. [PMID: 39322938 DOI: 10.1002/anie.202414810] [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: 08/05/2024] [Revised: 09/09/2024] [Accepted: 09/25/2024] [Indexed: 09/27/2024]
Abstract
Developing ionic copper-iodine clusters with multiple emitting is crucial for enriching lighting and display materials with various colors. However, the luminescent properties of traditional ionic copper-iodine clusters are often closely associated with low-energy cluster-centered triplet emission, which will redshift further as the Cu⋅⋅⋅Cu bond length decreases. This article utilizes a pressure-treated strategy to achieve an anomalous pressure-induced blue-shifted luminescence phenomenon in ionic Cu4I6(4-dimethylamino-1-ethylpyridinium)2 crystals for the first time, which is based on dominant through-space charge-transfer (TSCT). Herein, we reveal that the more advantageous through-space interactions in the competition between cuprophilic interactions and through-space interactions can lead to a blue-shifted luminescence. High-pressure angle-dispersive X-ray diffraction and high-pressure infrared experiments show that the enhanced through-space interactions mainly originate from forming new intermolecular C-H⋅⋅⋅I hydrogen bonds and the enhancement of van der Waals interactions between organic cations and anionic clusters. Theoretical calculations and experimental studies of excited-state dynamics confirm that the blue-shifted emission is due to the increased energy gap between the excited triplet and ground states caused by the electron delocalization under stronger through-space interactions. This work deepens previous understanding and provides a new avenue to design and synthetic ionic copper-iodine clusters with high-energy TSCT emission.
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Affiliation(s)
- Shanshan Wang
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
| | - Zhiqiang Yang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, China
| | - Xuening Sun
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
- Science and Information Technology, Liaocheng University, Liaocheng, 252000, China
| | - Min Wu
- Science and Information Technology, Liaocheng University, Liaocheng, 252000, China
| | - Kaiyang Sheng
- State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130012, China
- School of Electro-optical Engineering, Changchun University of Science and Technology, Changchun, 130022, China
| | - Long Zhang
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
- School of Materials Science and Engineering, Peking University, Beijing, 100871, China
| | - Bing Yang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, China
| | - Kai Wang
- Science and Information Technology, Liaocheng University, Liaocheng, 252000, China
| | - Yongming Sui
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
| | - Bo Zou
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun, 130012, China
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13
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Lan X, Zeng J, Chen J, Yang T, Dong X, Tang BZ, Zhao Z. Robust Sandwich-Structured Thermally Activated Delayed Fluorescence Molecules Utilizing 11,12-Dihydroindolo[2,3-a]carbazole as Bridge. Angew Chem Int Ed Engl 2025; 64:e202414488. [PMID: 39198216 DOI: 10.1002/anie.202414488] [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: 07/31/2024] [Revised: 08/27/2024] [Accepted: 08/27/2024] [Indexed: 09/01/2024]
Abstract
Constructing folded molecular structures is emerging as a promising strategy to develop efficient thermally activated delayed fluorescence (TADF) materials. Most folded TADF materials have V-shaped configurations formed by donors and acceptors linked on carbazole or fluorene bridges. In this work, a facile molecular design strategy is proposed for exploring sandwich-structured molecules, and a series of novel and robust TADF materials with regular U-shaped sandwich conformations are constructed by using 11,12-dihydroindolo[2,3-a]carbazole as bridge, xanthone as acceptor, and dibenzothiophene, dibenzofuran, 9-phenylcarbazole and indolo[3,2,1-JK]carbazole as donors. They hold outstanding thermal stability with ultrahigh decomposition temperatures (556-563 °C), and exhibit fast delayed fluorescence and excellent photoluminescence quantum efficiencies (86 %-97 %). The regular and close stacking of acceptor and donors results in rigidified molecular structures with efficient through-space interaction, which are conducive to suppressing intramolecular motion and reducing reorganized excited-state energy. The organic light-emitting diodes (OLEDs) using them as emitters exhibit excellent electroluminescence performances, with maximum external quantum efficiencies of up to 30.6 %, which is a leading value for the OLEDs based on folded TADF emitters. These results demonstrate the proposed strategy of employing 11,12-dihydroindolo[2,3-a]carbazole as bridge for planar donors and acceptors to construct efficient folded TADF materials is applicable.
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Affiliation(s)
- Xia Lan
- 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
| | - Jiajie Zeng
- 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
| | - Jinke Chen
- 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
| | - Tao Yang
- 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
| | - Xiaobin Dong
- 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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14
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Dos Santos JM, Hall D, Basumatary B, Bryden M, Chen D, Choudhary P, Comerford T, Crovini E, Danos A, De J, Diesing S, Fatahi M, Griffin M, Gupta AK, Hafeez H, Hämmerling L, Hanover E, Haug J, Heil T, Karthik D, Kumar S, Lee O, Li H, Lucas F, Mackenzie CFR, Mariko A, Matulaitis T, Millward F, Olivier Y, Qi Q, Samuel IDW, Sharma N, Si C, Spierling L, Sudhakar P, Sun D, Tankelevičiu Tė E, Duarte Tonet M, Wang J, Wang T, Wu S, Xu Y, Zhang L, Zysman-Colman E. The Golden Age of Thermally Activated Delayed Fluorescence Materials: Design and Exploitation. Chem Rev 2024; 124:13736-14110. [PMID: 39666979 DOI: 10.1021/acs.chemrev.3c00755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2024]
Abstract
Since the seminal report by Adachi and co-workers in 2012, there has been a veritable explosion of interest in the design of thermally activated delayed fluorescence (TADF) compounds, particularly as emitters for organic light-emitting diodes (OLEDs). With rapid advancements and innovation in materials design, the efficiencies of TADF OLEDs for each of the primary color points as well as for white devices now rival those of state-of-the-art phosphorescent emitters. Beyond electroluminescent devices, TADF compounds have also found increasing utility and applications in numerous related fields, from photocatalysis, to sensing, to imaging and beyond. Following from our previous review in 2017 ( Adv. Mater. 2017, 1605444), we here comprehensively document subsequent advances made in TADF materials design and their uses from 2017-2022. Correlations highlighted between structure and properties as well as detailed comparisons and analyses should assist future TADF materials development. The necessarily broadened breadth and scope of this review attests to the bustling activity in this field. We note that the rapidly expanding and accelerating research activity in TADF material development is indicative of a field that has reached adolescence, with an exciting maturity still yet to come.
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Affiliation(s)
- John Marques Dos Santos
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - David Hall
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Biju Basumatary
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Megan Bryden
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Dongyang Chen
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Praveen Choudhary
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Thomas Comerford
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Ettore Crovini
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Andrew Danos
- Department of Physics, Durham University, Durham DH1 3LE, UK
| | - Joydip De
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Stefan Diesing
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
- Organic Semiconductor Centre, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY169SS, UK
| | - Mahni Fatahi
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Máire Griffin
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Abhishek Kumar Gupta
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Hassan Hafeez
- Organic Semiconductor Centre, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY169SS, UK
| | - Lea Hämmerling
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Emily Hanover
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
- EaStCHEM School of Chemistry, The University of Edinburgh, Edinburgh, EH9 3FJ, UK
| | - Janine Haug
- Institute of Organic Chemistry (IOC), Karlsruhe Institute of Technology (KIT), Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany
| | - Tabea Heil
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Durai Karthik
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Shiv Kumar
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
- Department of Chemistry, University of Delhi, Delhi 110007, India
| | - Oliver Lee
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
- Organic Semiconductor Centre, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY169SS, UK
| | - Haoyang Li
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Fabien Lucas
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | | | - Aminata Mariko
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Tomas Matulaitis
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Francis Millward
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Yoann Olivier
- Laboratory for Computational Modeling of Functional Materials, Namur Institute of Structured Matter, Université de Namur, Rue de Bruxelles, 61, 5000 Namur, Belgium
| | - Quan Qi
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Ifor D W Samuel
- Organic Semiconductor Centre, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY169SS, UK
| | - Nidhi Sharma
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
- Organic Semiconductor Centre, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY169SS, UK
| | - Changfeng Si
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Leander Spierling
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Pagidi Sudhakar
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Dianming Sun
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Eglė Tankelevičiu Tė
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
- Organic Semiconductor Centre, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY169SS, UK
| | - Michele Duarte Tonet
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
- Organic Semiconductor Centre, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY169SS, UK
| | - Jingxiang Wang
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Tao Wang
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Sen Wu
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Yan Xu
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
| | - Le Zhang
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
- Organic Semiconductor Centre, SUPA School of Physics and Astronomy, University of St Andrews, St Andrews, Fife KY169SS, UK
| | - Eli Zysman-Colman
- Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY169ST, UK
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15
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Zhao G, Lv S, Lou Y, Zhang Y, Zhang D, Jiang W, Sun Y, Duan L. Cascade Effect of a Dimerized Thermally Activated Delayed Fluorescence Dendrimer. Angew Chem Int Ed Engl 2024; 63:e202412720. [PMID: 39082148 DOI: 10.1002/anie.202412720] [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: 07/06/2024] [Indexed: 11/05/2024]
Abstract
Thermally activated delayed fluorescence (TADF) emitters with a high horizontal orientation are highly essential for improving the external quantum efficiency (EQE) of organic light-emitting diodes; however, pivotal molecular design strategies to improve the horizontal orientation of solution-processable TADF emitters are still scarce and challenging. Herein, a phenyl bridge is adopted to connect the double TADF units, and generate a dimerized TADF dendrimer, D4CzBNPh-SF. Compared to its counterpart with a single TADF unit, the proof-of-the-concept molecule not only exhibits an improved horizontal dipole ratio (78 %) due to the π-delocalization-induced extended molecular conjugation, but also displays a faster reversed intersystem crossing rate constant (6.08×106 s-1) and a high photoluminescence quantum yield of 95 % in neat film. Consequently, the non-doped solution-processed device with D4CzBNPh-SF as the emitter achieves an ultra-high maximum EQE of 32.6 %, which remains at 26.6 % under a luminance of 1000 cd/m2. Furthermore, when using D4CzBNPh-SF as a sensitizer, the TADF-sensitized fluorescence device exhibits a high maximum EQE of 30.7 % at a luminance of 575 cd/m2 and a full width at half maximum of 36 nm.
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Affiliation(s)
- Guimin Zhao
- Jiangsu Province Hi-Tech Key Laboratory for Bio-Medical Research, Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device, School of Chemistry and Engineering, Southeast University, Nanjing, Jiangsu, 211189, China
| | - Shuai Lv
- Jiangsu Province Hi-Tech Key Laboratory for Bio-Medical Research, Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device, School of Chemistry and Engineering, Southeast University, Nanjing, Jiangsu, 211189, China
| | - Yuheng Lou
- Jiangsu Province Hi-Tech Key Laboratory for Bio-Medical Research, Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device, School of Chemistry and Engineering, Southeast University, Nanjing, Jiangsu, 211189, China
| | - Yuewei Zhang
- Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Dongdong Zhang
- Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Wei Jiang
- Jiangsu Province Hi-Tech Key Laboratory for Bio-Medical Research, Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device, School of Chemistry and Engineering, Southeast University, Nanjing, Jiangsu, 211189, China
| | - Yueming Sun
- Jiangsu Province Hi-Tech Key Laboratory for Bio-Medical Research, Jiangsu Engineering Laboratory of Smart Carbon-Rich Materials and Device, School of Chemistry and Engineering, Southeast University, Nanjing, Jiangsu, 211189, China
| | - Lian Duan
- Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing, 100084, China
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16
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Wang Y, Lv ZY, Chen ZX, Xing S, Huo ZZ, Hong XF, Yuan L, Li W, Zheng YX. Multiple-resonance thermally activated delayed fluorescence materials based on phosphorus central chirality for efficient circularly polarized electroluminescence. MATERIALS HORIZONS 2024; 11:4722-4729. [PMID: 38990337 DOI: 10.1039/d4mh00605d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/12/2024]
Abstract
Circularly polarized organic light-emitting diodes (CP-OLEDs) hold great potential for naked-eye 3D displays, necessitating efficient chiral luminescent materials with an optimal CP luminescence (CPL) dissymmetry factor (g). Herein, we present the first chiral multiple resonance thermally activated delayed fluorescence (MR-TADF) materials containing a phosphorus chiral center by incorporating 5-phenylbenzo[b]phosphindole-5-oxide into the para-position of two MR-TADF cores. The compounds, NBOPO and NBNPO, exhibit photoluminescence peaks at 462 and 498 nm with narrow full-width at half-maximum values of 25 and 24 nm in toluene, respectively. Notably, (R/S)-NBOPO and (R/S)-NBNPO enantiomers display high quantum yields of 87% and 93% and symmetric CPL with |gPL| factors of 1.18 × 10-3 and 4.30 × 10-3, respectively, in doped films. Moreover, the corresponding CP-OLEDs show impressive external quantum efficiencies of 16.4% and 28.3%, along with symmetric CP electroluminescence spectra with |gEL| values of 7.0 × 10-4 and 1.4 × 10-3, respectively.
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Affiliation(s)
- Yu Wang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China.
| | - Zi-Yi Lv
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China.
| | - Zi-Xuan Chen
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China.
| | - Shuai Xing
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China.
| | - Zhong-Zhong Huo
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China.
| | - Xian-Fang Hong
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China.
| | - Li Yuan
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China.
| | - Wei Li
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China.
| | - You-Xuan Zheng
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China.
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17
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Qu YK, Zhou DY, Zheng Q, Zuo P, Che ZL, Liao LS, Jiang ZQ. Linearly Arranged Multi-π-Stacked Structure for Efficient Through-Space Charge-Transfer Emitters. Angew Chem Int Ed Engl 2024; 63:e202408712. [PMID: 38962896 DOI: 10.1002/anie.202408712] [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: 05/08/2024] [Revised: 06/24/2024] [Accepted: 07/02/2024] [Indexed: 07/05/2024]
Abstract
Noncovalent spatial interaction has become an intriguing and important tool for constructing optoelectronic molecules. In this study, we linearly attached three conjugated units in a multi π-stacked manner by using just one trident bridge based on indeno[2,1-b]fluorene. To achieve this structure, we improved the synthetic approach through double C-H activation, significantly simplifying the preparation process. Due to the proximity of the C10, C11, and C12 sites in indeno[2,1-b]fluorene, we derived two novel donor|acceptor|donor (D|A|D) type molecules, 2DMB and 2DMFB, which exhibited closely packed intramolecular stacking, enabling efficient through-space charge transfer. This molecular construction is particularly suitable for developing high-performance thermally activated delayed fluorescence materials. With donor(s) and acceptor(s) constrained and separated within this spatially rigid structure, elevated radiative transition rates, and high photoluminescence quantum yields were achieved. Organic light-emitting diodes incorporating 2DMB and 2DMFB demonstrated superior efficiency, achieving maximum external quantum efficiencies of 28.6 % and 16.2 %, respectively.
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Affiliation(s)
- Yang-Kun Qu
- Institute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Dong-Ying Zhou
- Institute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Qi Zheng
- Institute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Peng Zuo
- Institute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Zong-Lu Che
- Institute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
| | - Liang-Sheng Liao
- Institute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
- Macao Institute of Materials Science and Engineering, Macau University of Science and Technology, Taipa, 999078, Macau SAR, China
| | - Zuo-Quan Jiang
- Institute of Functional Nano & Soft Materials (FUNSOM) and Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, 215123, Jiangsu, PR China
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18
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Wang RJ, Zheng F, Liu XL, Wu YL, Jin JM, Li ZY, Chen WC, Huo Y. A through-space charge transfer pyrene-based fluorophore with anti-quenching behavior for deep-blue organic light-emitting devices. Chem Commun (Camb) 2024; 60:7946-7949. [PMID: 38984894 DOI: 10.1039/d4cc02880e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2024]
Abstract
A through-space charge transfer pyrene-based fluorophore has been developed for organic light-emitting devices (OLEDs). This material exhibits deep-blue fluorescence, bipolar characteristics, and anti-quenching behavior in the solid state. It proves to be an effective emitter for both doped and nondoped deep-blue OLEDs.
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Affiliation(s)
- Ru-Jia Wang
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, P. R. China.
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang, P. R. China
| | - Fan Zheng
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, P. R. China.
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang, P. R. China
| | - Xiao-Long Liu
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, P. R. China.
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang, P. R. China
| | - Yu-Lan Wu
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, P. R. China.
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang, P. R. China
| | - Jia-Ming Jin
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, P. R. China.
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang, P. R. China
| | - Ze-Yan Li
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, P. R. China.
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang, P. R. China
| | - Wen-Cheng Chen
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, P. R. China.
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang, P. R. China
| | - Yanping Huo
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, P. R. China.
- Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center, Jieyang, P. R. China
- Analytical & Testing Center, Guangdong University of Technology, Guangzhou, P. R. China
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19
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Roy R, Brouillac C, Jacques E, Quinton C, Poriel C. π-Conjugated Nanohoops: A New Generation of Curved Materials for Organic Electronics. Angew Chem Int Ed Engl 2024; 63:e202402608. [PMID: 38744668 DOI: 10.1002/anie.202402608] [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: 02/05/2024] [Revised: 05/13/2024] [Accepted: 05/14/2024] [Indexed: 05/16/2024]
Abstract
Nanohoops, cyclic association of π-conjugated systems to form a hoop-shaped molecule, have been widely developed in the last 15 years. Beyond the synthetic challenge, the strong interest towards these molecules arises from their radially oriented π-orbitals, which provide singular properties to these fascinating structures. Thanks to their particular cylindrical arrangement, this new generation of curved molecules have been already used in many applications such as host-guest complexation, biosensing, bioimaging, solid-state emission and catalysis. However, their potential in organic electronics has only started to be explored. From the first incorporation as an emitter in a fluorescent organic light emitting diode (OLED), to the recent first incorporation as a host in phosphorescent OLEDs or as charge transporter in organic field-effect transistors and in organic photovoltaics, this field has shown important breakthroughs in recent years. These findings have revealed that curved materials can play a key role in the future and can even be more efficient than their linear counterparts. This can have important repercussions for the future of electronics. Time has now come to overview the different nanohoops used to date in electronic devices in order to stimulate the future molecular designs of functional materials based on these macrocycles.
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Affiliation(s)
- Rupam Roy
- Univ Rennes, CNRS, ISCR-UMR CNRS 6226, F-35000, Rennes, France
- Department of Chemistry, University of Florida, Gainesville, Florida, United States, 32603
| | | | | | | | - Cyril Poriel
- Univ Rennes, CNRS, ISCR-UMR CNRS 6226, F-35000, Rennes, France
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20
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Yang W, Xie C, Chen T, Yin X, Lin Q, Gong S, Quan Z, Yang C. Dynamic Reversible Full-Color Piezochromic Fluorogens Featuring Through-Space Charge-Transfer Thermally Activated Delayed Fluorescence and their Application as X-Ray Imaging Scintillators. Angew Chem Int Ed Engl 2024; 63:e202402704. [PMID: 38414169 DOI: 10.1002/anie.202402704] [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: 02/06/2024] [Revised: 02/27/2024] [Accepted: 02/27/2024] [Indexed: 02/29/2024]
Abstract
Thermally activated delayed fluorescence (TADF) emitters featuring through-space charge transfer (TSCT) can be excellent candidates for piezochromic luminescent (PCL) materials due to their structural dynamics. Spatial donor-acceptor (D-A) stacking arrangements enable the modulation of inter- and intramolecular D-A interactions, as well as spatial charge transfer states, under varying pressure conditions. Herein, we demonstrate an effective approach toward dynamic reversible full-color PCL materials with TSCT-TADF characteristics. Their single crystals exhibit a full-color-gamut PCL process spanning a range of 170 nm. Moreover, the TSCT-TADF-PCL emitters display a unity photoluminescence quantum yield, and show promising application in X-ray scintillator imaging.
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Affiliation(s)
- Wei Yang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, People's Republic of China
| | - Chenlong Xie
- Department of Chemistry, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology (SUSTech), Shenzhen, Guangdong 518055, China
| | - Tianhao Chen
- Department of Chemistry, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan, 430072, People's Republic of China
| | - Xiaojun Yin
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, People's Republic of China
| | - Qianqian Lin
- Key Lab of Artificial Micro- and Nano-Structures of Ministry of Education of China, School of Physics and Technology, Wuhan University, Wuhan, 430072, People's Republic of China
| | - Shaolong Gong
- Department of Chemistry, Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Wuhan University, Wuhan, 430072, People's Republic of China
| | - Zewei Quan
- Department of Chemistry, Academy for Advanced Interdisciplinary Studies, Southern University of Science and Technology (SUSTech), Shenzhen, Guangdong 518055, China
| | - Chuluo Yang
- Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518060, People's Republic of China
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21
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Li Q, Zhao Z, Zhao H, Guo Y, Tong X, Yan S, Ren Z. Enhancing Light-Emitting Efficiency of Blue Through-Space Charge Transfer Emitters via Fixing Configuration Induced by Intramolecular Hydrogen Bonding. ACS APPLIED MATERIALS & INTERFACES 2024; 16:22238-22247. [PMID: 38634459 DOI: 10.1021/acsami.4c01219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Closely aligned configuration of the donor (D) and acceptor (A) is crucial for the light-emitting efficiency of thermally activated delayed fluorescence (TADF) materials with through-space charge transfer (TSCT) characteristics. However, precisely controlling the D-A distance of blue TSCT-TADF emitters is still challenging. Herein, an extra donor (D*) located on the side of the primary donor (D) is introduced to construct the hydrogen bonding with A and thus modulate the distance of D and A units to prepare high-efficiency blue TSCT emitters. The obtained "V"-shaped TSCT emitter presents a minimal D-A distance of 2.890 Å with a highly parallel D-A configuration. As a result, a high rate of radiative decay (>107 s-1) and photoluminescence quantum yield (nearly 90%) are achieved. The corresponding blue organic light-emitting diodes show maximum external quantum efficiencies (EQEmax) of 27.9% with a Commission Internationale de L'Eclairage (CIE) coordinate of (0.16, 0.21), which is the highest device efficiency of fluorene-based blue TSCT-TADF emitters. In addition, the TSCT-TADF emitter-sensitized OLEDs also achieve a high EQEmax of 29.3% with a CIE coordinate of (0.12, 0.16) and a narrow emission.
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Affiliation(s)
- Quanwei Li
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Zhennan Zhao
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Haisong Zhao
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Yumeng Guo
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Xingwen Tong
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Shouke Yan
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
- Key Laboratory of Rubber-Plastics Ministry of Education, Qingdao University of Science & Technology, Qingdao 266042, PR China
| | - Zhongjie Ren
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
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22
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Lee KW, Wan Y, Huang Z, Zhao Q, Li S, Lee CS. Organic Optoelectronic Materials: A Rising Star of Bioimaging and Phototherapy. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2306492. [PMID: 37595570 DOI: 10.1002/adma.202306492] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/07/2023] [Indexed: 08/20/2023]
Abstract
Recently, many organic optoelectronic materials (OOMs), especially those used in organic light-emitting diodes (OLEDs), organic solar cells (OSCs), and organic field-effect transistors (OFETs), are explored for biomedical applications including imaging and photoexcited therapies. In this review, recently developed OOMs for fluorescence imaging, photoacoustic imaging, photothermal therapy, and photodynamic therapy, are summarized. Relationships between their molecular structures, nanoaggregation structures, photophysical mechanisms, and properties for various biomedical applications are discussed. Mainly four kinds of OOMs are covered: thermally activated delayed fluorescence materials in OLEDs, conjugated small molecules and polymers in OSCs, and charge-transfer complexes in OFETs. Based on the OOMs unique optical properties, including excitation light wavelength and exciton dynamics, they are respectively exploited for suitable biomedical applications. This review is intended to serve as a bridge between researchers in the area of organic optoelectronic devices and those in the area of biomedical applications. Moreover, it provides guidance for selecting or modifying OOMs for high-performance biomedical uses. Current challenges and future perspectives of OOMs are also discussed with the hope of inspiring further development of OOMs for efficient biomedical applications.
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Affiliation(s)
- Ka-Wai Lee
- Center of Super-Diamond and Advanced Films (COSDAF), Department of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, P. R. China
| | - Yingpeng Wan
- Center of Super-Diamond and Advanced Films (COSDAF), Department of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, P. R. China
- College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Zhongming Huang
- College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Qi Zhao
- College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Shengliang Li
- College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Chun-Sing Lee
- Center of Super-Diamond and Advanced Films (COSDAF), Department of Chemistry, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong SAR, P. R. China
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23
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Diesing S, Zhang L, Zysman-Colman E, Samuel IDW. A figure of merit for efficiency roll-off in TADF-based organic LEDs. Nature 2024; 627:747-753. [PMID: 38538942 PMCID: PMC10972759 DOI: 10.1038/s41586-024-07149-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 02/01/2024] [Indexed: 04/01/2024]
Abstract
Organic light-emitting diodes (OLEDs) are a revolutionary light-emitting display technology that has been successfully commercialized in mobile phones and televisions1,2. The injected charges form both singlet and triplet excitons, and for high efficiency it is important to enable triplets as well as singlets to emit light. At present, materials that harvest triplets by thermally activated delayed fluorescence (TADF) are a very active field of research as an alternative to phosphorescent emitters that usually use heavy metal atoms3,4. Although excellent progress has been made, in most TADF OLEDs there is a severe decrease of efficiency as the drive current is increased, known as efficiency roll-off. So far, much of the literature suggests that efficiency roll-off should be reduced by minimizing the energy difference between singlet and triplet excited states (ΔEST) to maximize the rate of conversion of triplets to singlets by means of reverse intersystem crossing (kRISC)5-20. We analyse the efficiency roll-off in a wide range of TADF OLEDs and find that neither of these parameters fully accounts for the reported efficiency roll-off. By considering the dynamic equilibrium between singlets and triplets in TADF materials, we propose a figure of merit for materials design to reduce efficiency roll-off and discuss its correlation with reported data of TADF OLEDs. Our new figure of merit will guide the design and development of TADF materials that can reduce efficiency roll-off. It will help improve the efficiency of TADF OLEDs at realistic display operating conditions and expand the use of TADF materials to applications that require high brightness, such as lighting, augmented reality and lasing.
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Affiliation(s)
- S Diesing
- Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
- Organic Semiconductor Centre, EaStCHEM, School of Chemistry, St Andrews, UK
| | - L Zhang
- Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK
- Organic Semiconductor Centre, EaStCHEM, School of Chemistry, St Andrews, UK
| | - E Zysman-Colman
- Organic Semiconductor Centre, EaStCHEM, School of Chemistry, St Andrews, UK.
| | - I D W Samuel
- Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews, UK.
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24
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He X, Lou J, Li B, Dong X, Zhong F, Liu W, Feng X, Yang D, Ma D, Zhao Z, Wang Z, Tang BZ. Rational Medium-Range Charge Transfer Strategy Toward Highly Efficient Violet-Blue Organic Light-Emitting Diodes with Narrowed Emission. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2310417. [PMID: 37971674 DOI: 10.1002/adma.202310417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 11/01/2023] [Indexed: 11/19/2023]
Abstract
The spectral narrowing engineering of pure-organic emitters attracts great research interests in realizing high color purity. Here, the adjusted medium-range charge transfer (MCT) strategy of TIC-BO with rigid planar structure by fusing two typical UV-emitting multiple resonance (MR) fragments via the ingenious double-halide cyclized coupling reaction is reported. The resulting TIC-BO with MCT nature shows efficient violet-blue emission in dilute toluene and evaporated host-guest films, and desirably narrowed spectra are achieved by the suppression of structural relaxation and the shortened charge transfer states. The single-doped device with TIC-BO as emitter shows narrowed violet-blue electroluminescence peaked at 428 nm with full-width at half-maximum of 43 nm (0.28 eV), and the Commission Internationale de l'Éclairage coordinates of (0.160, 0.050). A maximum external quantum efficiency (EQEmax ) of 20.50% is achieved, which is among the best results of the corresponding violet-blue emitting region. Further introduction of a stronger electron-donating carbazole group makes TIC-BNO exhibit red-shifted sky-blue emission with MR-dominant properties, and good device performance is received with EQEmax of 34.58%. The outstanding performances of TIC-BO successfully demonstrate the significance and prospect of the proposed molecular design strategy.
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Affiliation(s)
- Xin He
- AIE Institute, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology (SCUT), Guangzhou, 510640, P. R. China
| | - Jingli Lou
- AIE Institute, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology (SCUT), Guangzhou, 510640, P. R. China
| | - Baoxi Li
- AIE Institute, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology (SCUT), Guangzhou, 510640, P. R. China
| | - Xiaobin Dong
- AIE Institute, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology (SCUT), Guangzhou, 510640, P. R. China
| | - Feiyang Zhong
- AIE Institute, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology (SCUT), Guangzhou, 510640, P. R. China
| | - Wei Liu
- Guangdong Provincial Key Laboratory of Information Photonics Technology, School of Material and Energy, Guangdong University of Technology, Guangzhou, 510006, P. R. China
| | - Xing Feng
- Guangdong Provincial Key Laboratory of Information Photonics Technology, School of Material and Energy, Guangdong University of Technology, Guangzhou, 510006, P. R. China
| | - Dezhi Yang
- AIE Institute, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology (SCUT), Guangzhou, 510640, P. R. China
| | - Dongge Ma
- AIE Institute, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology (SCUT), Guangzhou, 510640, P. R. China
| | - Zujin Zhao
- AIE Institute, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology (SCUT), Guangzhou, 510640, P. R. China
| | - Zhiming Wang
- AIE Institute, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology (SCUT), Guangzhou, 510640, P. R. China
| | - Ben Zhong Tang
- AIE Institute, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, Center for Aggregation-Induced Emission, South China University of Technology (SCUT), Guangzhou, 510640, P. R. China
- Shenzhen Institute of Aggregate Science and Technology, School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen (CUHK-Shenzhen), Shenzhen, 518172, P. R. China
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25
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Poriel C, Rault-Berthelot J. Dihydroindenofluorenes as building units in organic semiconductors for organic electronics. Chem Soc Rev 2023; 52:6754-6805. [PMID: 37702538 DOI: 10.1039/d1cs00993a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/14/2023]
Abstract
This review aims to discuss organic semiconductors constructed on dihydroindenofluorene positional isomers, which are key molecular scaffolds in organic electronics. Bridged oligophenylenes are key organic semiconductors that have allowed the development of organic electronic technologies. Dihydroindenofluorenes (DHIFs) belong to the family of bridged oligophenylenes constructed on a terphenyl backbone. They have proven to be very promising building blocks for the construction of highly efficient organic semiconductors for all OE devices, namely organic light emitting diodes (OLEDs), phosphorescent OLEDs, organic field-effect transistors (OFETs), solar cells, etc.
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Affiliation(s)
- Cyril Poriel
- UMR CNRS 6226-Université Rennes 1-ISCR-Campus de Beaulieu, 35042 Rennes, France.
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26
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Woo JY, Park MH, Jeong SH, Kim YH, Kim B, Lee TW, Han TH. Advances in Solution-Processed OLEDs and their Prospects for Use in Displays. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2207454. [PMID: 36300804 DOI: 10.1002/adma.202207454] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/05/2022] [Indexed: 06/16/2023]
Abstract
This review outlines problems and progress in development of solution-processed organic light-emitting diodes (SOLEDs) in industry and academia. Solution processing has several advantages such as low consumption of materials, low-cost processing, and large-area manufacturing. However, use of a solution process entails complications, such as the need for solvent resistivity and solution-processable materials, and yields SOLEDs that have limited luminous efficiency, severe roll-off characteristics, and short lifetime compared to OLEDs fabricated using thermal evaporation. These demerits impede production of practical SOLED displays. This review outlines the industrial demands for commercial SOLEDs and the current status of SOLED development in industries and academia, and presents research guidelines for the development of SOLEDs that have high efficiency, long lifetime, and good processability to achieve commercialization.
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Affiliation(s)
- Joo Yoon Woo
- Division of Materials Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea
| | - Min-Ho Park
- Department of Organic Materials and Fiber Engineering, Soongsil University, 369 Sangdo-Ro, Dongjak-Gu, Seoul, 06978, Republic of Korea
| | - Su-Hun Jeong
- Future Technology Research Center, LG Chem, Ltd., 30, Magokjunang 10-ro, Gangseo-gu, Seoul, 07794, Republic of Korea
| | - Young-Hoon Kim
- Department of Energy Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea
| | - Byungjae Kim
- Future Technology Research Center, LG Chem, Ltd., 30, Magokjunang 10-ro, Gangseo-gu, Seoul, 07794, Republic of Korea
| | - Tae-Woo Lee
- Department of Materials Science and Engineering, School of Chemical and Biological Engineering, Institute of Engineering Research, Research Institute of Advanced Materials, Soft Foundry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Tae-Hee Han
- Division of Materials Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea
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Zhang T, Xiao Y, Wang H, Kong S, Huang R, Ka-Man Au V, Yu T, Huang W. Highly Twisted Thermally Activated Delayed Fluorescence (TADF) Molecules and Their Applications in Organic Light-Emitting Diodes (OLEDs). Angew Chem Int Ed Engl 2023; 62:e202301896. [PMID: 37288654 DOI: 10.1002/anie.202301896] [Citation(s) in RCA: 50] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 06/07/2023] [Accepted: 06/07/2023] [Indexed: 06/09/2023]
Abstract
Thermally activated delayed fluorescence (TADF) materials have attracted great potential in the field of organic light-emitting diodes (OLEDs). Among thousands of TADF materials, highly twisted TADF emitters have become a hotspot in recent years. Compared with traditional TADF materials, highly twisted TADF emitters tend to show multi-channel charge-transfer characters and form rigid molecular structures. This is advantageous for TADF materials, as non-radiative decay processes can be suppressed to facilitate efficient exciton utilization. Accordingly, OLEDs with excellent device performances have also been reported. In this Review, we have summarized recent progress in highly twisted TADF materials and related devices, and give an overview of the molecular design strategies, photophysical studies, and the performances of OLED devices. In addition, the challenges and perspectives of highly twisted TADF molecules and the related OLEDs are also discussed.
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Affiliation(s)
- Tiantian Zhang
- Frontiers Science Center for Flexible Electronics (FSCFE), Xi'an Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, 127 West Youyi Road, 710072, Xi'an, China
| | - Yuxin Xiao
- Frontiers Science Center for Flexible Electronics (FSCFE), Xi'an Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, 127 West Youyi Road, 710072, Xi'an, China
| | - Hailan Wang
- Frontiers Science Center for Flexible Electronics (FSCFE), Xi'an Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, 127 West Youyi Road, 710072, Xi'an, China
| | - Shuting Kong
- Frontiers Science Center for Flexible Electronics (FSCFE), Xi'an Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, 127 West Youyi Road, 710072, Xi'an, China
| | - Rongjuan Huang
- Frontiers Science Center for Flexible Electronics (FSCFE), Xi'an Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, 127 West Youyi Road, 710072, Xi'an, China
| | - Vonika Ka-Man Au
- Department of Science and Environmental Studies, The Education University of Hong Kong, 10 Lo Ping Road, Tai Po, New Territories, Hong Kong, China
| | - Tao Yu
- Frontiers Science Center for Flexible Electronics (FSCFE), Xi'an Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, 127 West Youyi Road, 710072, Xi'an, China
- Key Laboratory of Flexible Electronics of Zhejiang Province, Ningbo Institute of Northwestern Polytechnical University, 218 Qingyi Road, 315103, Ningbo, China
| | - Wei Huang
- Frontiers Science Center for Flexible Electronics (FSCFE), Xi'an Institute of Flexible Electronics (IFE), Northwestern Polytechnical University, 127 West Youyi Road, 710072, Xi'an, China
- Key Laboratory of Flexible Electronics & Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, 211816, Nanjing, China
- State Key Laboratory of Organic Electronics and Information Displays &, Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, 210023, Nanjing, China
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Ma B, Ding Z, Liu D, Zhou Z, Zhang K, Dang D, Zhang S, Su SJ, Zhu W, Liu Y. A Feasible Strategy for a Highly Efficient Thermally Activated Delayed Fluorescence Emitter Over 900 nm Based on Phenalenone Derivatives. Chemistry 2023; 29:e202301197. [PMID: 37154226 DOI: 10.1002/chem.202301197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 05/05/2023] [Accepted: 05/08/2023] [Indexed: 05/10/2023]
Abstract
Near-infrared (NIR) organic light-emitting diodes (OLEDs) suffer from the low external electroluminescence (EL) quantum efficiency (EQE), which is a critical obstacle for potential applications. Herein, 1-oxo-1-phenalene-2,3-dicarbonitrile (OPDC) is employed as an electron-withdrawing aromatic ring, and by incorporating with triphenylamine (TPA) and biphenylphenylamine (BBPA) donors, two novel NIR emitters with thermally activated delayed fluorescence (TADF) characteristics, namely OPDC-DTPA and OPDC-DBBPA, are first developed and compared in parallel. Intense NIR emission peaks at 962 and 1003 nm are observed in their pure films, respectively. Contributed by the local excited (LE) characteristics in the triplet (T1 ) state in synergy with the charge transfer (CT) characteristics for the singlet (S1 ) state to activate TADF emission, the solution processable doped NIR OLEDs based on OPDC-DTPA and OPDC-DBBPA yield EL peaks at 834 and 906 nm, accompanied with maximum EQEs of 0.457 and 0.103 %, respectively, representing the state-of-the-art EL performances in the TADF emitter-based NIR-OLEDs in the similar EL emission regions so far. This work manifests a simple and effective strategy for the development of NIR TADF emitters with long wavelength and efficiency synchronously.
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Affiliation(s)
- Bin Ma
- School of Materials Science and Engineering, Jiangsu Engineering Research Center of Light-Electricity-Heat Energy-Converting Materials and Applications, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Key Laboratories of Environment-Friendly Polymers, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Zhenming Ding
- School of Materials Science and Engineering, Jiangsu Engineering Research Center of Light-Electricity-Heat Energy-Converting Materials and Applications, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Key Laboratories of Environment-Friendly Polymers, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Denghui Liu
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices, South China University of Technology, Guangzhou, 510640, P. R. China
| | - Zhongxin Zhou
- School of Materials Science and Engineering, Jiangsu Engineering Research Center of Light-Electricity-Heat Energy-Converting Materials and Applications, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Key Laboratories of Environment-Friendly Polymers, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Kai Zhang
- School of Materials Science and Engineering, Jiangsu Engineering Research Center of Light-Electricity-Heat Energy-Converting Materials and Applications, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Key Laboratories of Environment-Friendly Polymers, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Dongfeng Dang
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, P. R. China
| | - Shiyue Zhang
- School of Materials Science and Engineering, Jiangsu Engineering Research Center of Light-Electricity-Heat Energy-Converting Materials and Applications, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Key Laboratories of Environment-Friendly Polymers, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Shi-Jian Su
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices, South China University of Technology, Guangzhou, 510640, P. R. China
| | - Weiguo Zhu
- School of Materials Science and Engineering, Jiangsu Engineering Research Center of Light-Electricity-Heat Energy-Converting Materials and Applications, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Key Laboratories of Environment-Friendly Polymers, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou, 213164, P. R. China
| | - Yu Liu
- School of Materials Science and Engineering, Jiangsu Engineering Research Center of Light-Electricity-Heat Energy-Converting Materials and Applications, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Key Laboratories of Environment-Friendly Polymers, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University, Changzhou, 213164, P. R. China
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Zhao Z, Yan S, Ren Z. Regulating the Nature of Triplet Excited States of Thermally Activated Delayed Fluorescence Emitters. Acc Chem Res 2023. [PMID: 37364229 DOI: 10.1021/acs.accounts.3c00175] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
ConspectusCharacterized by the reverse intersystem crossing (RISC) process from the triplet state (T1) to the singlet state (S1), thermally activated delayed fluorescence (TADF) emitters, which produce light by harvesting both triplet and singlet excitons without noble metals, are considered to be third-generation organic electroluminescent materials. Rapid advances in molecular design criteria, understanding the photophysics underlying TADF, and applications of TADF materials as emitters in organic light-emitting diodes (OLEDs) have been achieved. Theoretically, enhanced spin-orbit coupling (SOC) between singlet and triplet states can result in a fast RISC process and thus a high light-emitting efficiency according to Fermi's golden rule. Therefore, regulating the nature of triplet excited states by elaborate molecular design to improve SOC is an effective approach to high-efficiency TADF-based OLEDs. Generally, on one hand, the increased local excited (LE) populations of the excited triplet state can significantly improve the nature flips between S1 and T1. On other hand, the reduced energy gap between S1 and the lowest triplet with a charge transfer (CT) characteristic can also enhance their vibronic coupling. Consequently, it is vital to determine how to regulate the nature of triplet excited states by molecular design to guide the material synthesis, especially for polymeric emitters.In this Account, we focus on modulating the strategy of triplet excited states for TADF emitters and an in-depth understanding of the photophysical processes, leading to optimized OLED device performance. We include several kinds of strategies to control the nature of triplet excited states to guide the synthesis of small-molecule and polymer TADF emitters: (1) Modulating the electronic distribution of conjugated polymeric backbones by copolymerizing the electron-donating host: accordingly, the nature of excited states can be changed, especially for triplets. Meanwhile, the utilization of excitons can be systematically improved by adjusting the electronic structure of triplet states with long-range distribution in the conjugated polymeric backbones. (2) Halogenating acceptors of TADF units: the introduced halogen atoms would reestablish the electronic distribution of the triplet and relocate the hole orbits, resulting in a CT and LE hybrid nature of a triplet transformed into a LE-predominant state, which favors the RISC process. (3) Stereostructure regulation: by constructing a diverse arrangement of three-dimensional spatial configurations or conjugated architectures, the nature of the triplet can also be finely tuned, such as hyperbranched structures with multiple triplet-singlet vibration couplings, half-dendronized-half-encapsulated asymmetric systems, trinaphtho[3,3,3] propeller-based three-dimensional spatial interspersed structures, intramolecular close-packed donor-acceptor systems, and so on. We hope that this Account will provide insights into new structures and mechanisms for achieving high-performance OLEDs based on regulating the nature of triplet excited states.
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Affiliation(s)
- Zhennan Zhao
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Shouke Yan
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China
- Key Laboratory of Rubber-Plastics, Ministry of Education, Qingdao University of Science & Technology, Qingdao 266042, China
| | - Zhongjie Ren
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China
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Kothavale S, Kim SC, Cheong K, Zeng S, Wang Y, Lee JY. Solution-Processed Pure Red TADF Organic Light-Emitting Diodes With High External Quantum Efficiency and Saturated Red Emission Color. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2208602. [PMID: 36653735 DOI: 10.1002/adma.202208602] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 12/29/2022] [Indexed: 06/17/2023]
Abstract
In spite of recent research progress in red thermally activated delayed fluorescence (TADF) emitters, highly efficient solution-processable pure red TADF emitters are rarely reported. Most of the red TADF emitters reported to date are designed using a rigid acceptor unit which renders them insoluble and unsuitable for solution-processed organic light-emitting diodes (OLEDs). To resolve this issue, a novel TADF emitter, 6,7-bis(4-(bis(4-(tert-butyl)phenyl)amino)phenyl)-2,3-bis(4-(tert-butyl)phenyl)quinoxaline-5,8-dicarbonitrile (tBuTPA-CNQx) is designed and synthesized. The highly twisted donor-acceptor architecture and appropriate highest occupied molecular orbital/lowest unoccupied molecular orbital distribution lead to a very small singlet-triplet energy gap of 0.07 eV, high photoluminescence quantum yield of 92%, and short delayed fluorescence lifetime of 52.4 µs. The peripheral t-butyl phenyl decorated quinoxaline acceptor unit and t-butyl protected triphenylamine donor unit are proven to be useful building blocks to improve solubility and minimize the intermolecular interaction. The solution-processed OLED based on tBuTPA-CNQx achieves a high external quantum efficiency (EQE) of 16.7% with a pure red emission peak at 662 nm, which is one of the highest EQE values reported till date in the solution-processed pure red TADF OLEDs. Additionally, vacuum-processable OLED based on tBuTPA-CNQx exhibits a high EQE of 22.2% and negligible efficiency roll-off.
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Affiliation(s)
- Shantaram Kothavale
- School of Chemical Engineering, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi, 16419, Republic of Korea
| | - Seung Chan Kim
- School of Chemical Engineering, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi, 16419, Republic of Korea
| | - Kiun Cheong
- School of Chemical Engineering, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi, 16419, Republic of Korea
| | - Songkun Zeng
- School of Materials Science & Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Yafei Wang
- School of Materials Science & Engineering, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Jun Yeob Lee
- School of Chemical Engineering, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi, 16419, Republic of Korea
- SKKU Advanced Institute of Nano Technology, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi, 16419, Republic of Korea
- SKKU Institute of Energy Science and Technology, Sungkyunkwan University, 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi, 16419, Republic of Korea
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Kumar K, Kesavan KK, Kumar S, Banik S, Jayakumar J, Hong LY, Hung LY, Nagar MR, Jou JH, Ghosh S. Decorated pyridine as hole transporting material (HTM) for solution-processed OLEDs. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2022.114380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Liu Y, Yang J, Mao Z, Wang Y, Zhao J, Su SJ, Chi Z. Isomeric thermally activated delayed fluorescence emitters for highly efficient organic light-emitting diodes. Chem Sci 2023; 14:1551-1556. [PMID: 36794188 PMCID: PMC9906651 DOI: 10.1039/d2sc06335b] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/12/2023] [Indexed: 01/13/2023] Open
Abstract
The isomeric strategy is an important design concept in molecular design that has a non-negligible influence on molecular properties. Herein, two isomeric thermally activated delayed fluorescence (TADF) emitters (NTPZ and TNPZ) are constructed with the same skeleton consisting of an electron donor and electron acceptor but different connection sites. Systematic investigations show that NTPZ exhibits a small energy gap, large up-conversion efficiency, low non-radiative decay, and high photoluminescence quantum yield. Further theoretical simulations reveal that the excited molecular vibrations play a key role in regulating the non-radiative decays of the isomers. Therefore, an NTPZ based OLED achieves better electroluminescence performances, such as a higher external quantum efficiency of 27.5% compared to a TNPZ based OLED (18.3%). This isomeric strategy not only provides an opportunity to deeply understand the relationship between substituent locations and molecular properties, but also affords a simple and effective strategy to enrich TADF materials.
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Affiliation(s)
- Yanyan Liu
- PCFM Lab, GDHPPC Lab, Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films, State Key Laboratory of OEMT, School of Chemistry, Sun Yat-sen University Guangzhou 510275 China
| | - Jiaji Yang
- State Key Laboratory of Luminescent Materials and Devices, Institute of Polymer Optoelectronic Materials and Devices, South China University of Technology Guangzhou 510640 China
| | - Zhu Mao
- Shenzhen Institute of Advanced Electronic Materials, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences Shenzhen 518055 China
| | - Yuyuan Wang
- PCFM Lab, GDHPPC Lab, Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films, State Key Laboratory of OEMT, School of Chemistry, Sun Yat-sen University Guangzhou 510275 China
| | - Juan Zhao
- School of Materials Science and Engineering, Sun Yat-sen University Guangzhou 510275 China
| | - Shi-Jian Su
- State Key Laboratory of Luminescent Materials and Devices, Institute of Polymer Optoelectronic Materials and Devices, South China University of Technology Guangzhou 510640 China
| | - Zhenguo Chi
- PCFM Lab, GDHPPC Lab, Guangdong Engineering Technology Research Center for High-performance Organic and Polymer Photoelectric Functional Films, State Key Laboratory of OEMT, School of Chemistry, Sun Yat-sen University Guangzhou 510275 China
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Zou H, Liu H, Mu Q, Zhang K, Song Y, Lin L, Xu Y, Wang CK, Fan J. Theoretical perspective for substitution effect on luminescent properties of through space charge transfer-based thermally activated delayed fluorescence molecules. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 285:121899. [PMID: 36179564 DOI: 10.1016/j.saa.2022.121899] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 09/03/2022] [Accepted: 09/13/2022] [Indexed: 06/16/2023]
Abstract
Recently, through space charge transfer (TSCT)-based thermally activated delayed fluorescence (TADF) molecules have shown advantages in achieving high efficiencies and tunable emissions. However, the relationships between basic molecular structures and luminescent properties are unclear. Theoretical investigations to reveal the substitution effects with different numbers and positions on excited-state properties are highly desired. Herein, by taking TSCT-based TADF molecules S-CNDF-S-tCz, S-CNDF-D-tCz and T-CNDF-T-tCz as skeletons, a series of promising TADF molecules are designed by adopting ortho, meta and para substitutions with different numbers and positions. Photophysical properties of total 16 molecules are theoretically studied by density functional theory (DFT) and time-dependent density functional theory (TD-DFT) methods in chloroform combined with polarizable continuum model. Results indicate that molecules with ortho-substitution possess small geometric changes and short Donor-Acceptor distances which are induced by the intramolecular van der Waals interactions. Decreased non-radiative consumption and increased TSCT ratio and therefore excellent performance for them can be expected. For molecules with large substitution numbers, twist structures facilitate them to realize small adiabatic energy gaps between the lowest singlet excited state (S1) and the lowest triplet excited state (T1), this designing strategy is consistent with the TADF dendrimers. Thus, the relationships between molecular structures and luminescent properties are revealed and promising TSCT-based TADF molecules with high efficiencies are theoretically proposed. Our investigations provide theoretical perspectives for inner mechanisms of substitution effect, which could further afford meaningful guidance to design new efficient TSCT-based TADF molecules.
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Affiliation(s)
- Haipei Zou
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Huanling Liu
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Qingfang Mu
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Kai Zhang
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Yuzhi Song
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Lili Lin
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Yuanyuan Xu
- Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
| | - Chuan-Kui Wang
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
| | - Jianzhong Fan
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China; Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates (South China University of Technology), Guangzhou 510640, China.
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Liu H, Zhang K, Zou H, Mu Q, Song Y, Lin L, Xu Y, Wang CK, Fan J. Controllable construction of red thermally activated delayed fluorescence molecules based on a spiro-acridine donor. Phys Chem Chem Phys 2023; 25:1032-1044. [PMID: 36537471 DOI: 10.1039/d2cp05084f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Red and near-infrared (NIR) thermally activated delayed fluorescence (TADF) molecules show excellent potential applications in organic light-emitting diodes (OLEDs). Due to the lack of systematic studies on the relationship between molecular structures and luminescence properties, both the species and amounts of red and NIR TADF molecules are far from meeting the requirements for practical applications. Herein, four new efficient molecules (DQCN-2spAs, TPCN-2spAs, DPCN-2spAs and BPCN-2spAs) are proposed and their photophysical properties are theoretically predicted based on first-principles calculations and thermal vibration correlation function (TVCF) theory. The results show that all molecules exhibit red or NIR emissions and they have fast radiative decay rates and reverse intersystem crossing (RISC) rates, and the excellent TADF luminescence properties are predicted. Moreover, based on spiro-acridine (spAs) as the donor unit, the combination with different acceptors can change the dihedral angle between the ground state and the excited state, the bending degree of the donor is positively correlated with the reorganization energy, and this feature can have a great influence on the non-radiative process. Furthermore, based on these theoretical predictions, experimental verifications are performed and the synthesized BPCN-2spAs is confirmed to be an efficient NIR TADF molecule. Thus, the relationships between basic molecular structures and photophysical properties are revealed, a feasible design strategy is applied and four promising red and NIR TADF molecules are proposed. All these results could contribute to the development of red and NIR TADF emitters and OLEDs.
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Affiliation(s)
- Huanling Liu
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
| | - Kai Zhang
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
| | - Haipei Zou
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
| | - Qingfang Mu
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
| | - Yuzhi Song
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
| | - Lili Lin
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
| | - Yuanyuan Xu
- School of Science, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
| | - Chuan-Kui Wang
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
| | - Jianzhong Fan
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, Institute of Materials and Clean Energy, School of Physics and Electronics, Shandong Normal University, Jinan 250014, China. .,Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates (South China University of Technology), Guangzhou 510640, China
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Wang Q, Xu Y, Yang T, Xue J, Wang Y. Precise Functionalization of a Multiple-Resonance Framework: Constructing Narrowband Organic Electroluminescent Materials with External Quantum Efficiency over 40. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2205166. [PMID: 36325646 DOI: 10.1002/adma.202205166] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 10/10/2022] [Indexed: 06/16/2023]
Abstract
It is of important strategic significance to develop high-efficiency narrowband organic electroluminescent materials that can be employed to fabricate ultrahigh-definition displays with wide color gamut. This topic implies a great challenge to molecular design and synthesis, especially for the development of universality, diversity, scalability, and robustness of molecular architectonics. In this work, a synthetic methodology is demonstrated for functionalizing brominated BN-containing multiple-resonance (MR) frameworks with multifarious functional groups, such as donors, acceptors, and moieties without obvious push-pull electron properties. The m-DPAcP-BNCz-based organic light-emitting diode (OLED) exhibits green emission with a full-width at half-maximum (FWHM) of 28 nm and a maximum external quantum efficiency (EQE) of 40.6%. The outstanding performance of m-DPAcP-BNCz is attributed to the perfect integration of the inherent advantages of the MR framework and the donor-acceptor configuration, which can not only achieve bathochromic shift and narrowband emission, but also obtain high photoluminescence (PL) quantum yield (ΦPL ) and horizontal emitting dipole orientation ratio (Θ// ). This straightforward and efficient approach provides insightful guidance for the construction and enrichment of more high-efficiency narrowband emitters.
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Affiliation(s)
- Qingyang Wang
- 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
| | - Tong Yang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012, P. R. China
| | - Jianan Xue
- 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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36
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Liang Y, Xu M, Chi Y, Liang T, Jiang X, Wang J, Pan Y, Yang B. Theoretical study of the thermally activated delayed fluorescence (TADF) combined with aggregation-induced emission (AIE) molecular solid-state effect on the luminescence mechanism. Chem Phys Lett 2023. [DOI: 10.1016/j.cplett.2022.140257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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37
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Meng SG, Zhu XZ, Zhou DY, Liao LS. Recent Progresses in Solution-Processed Tandem Organic and Quantum Dots Light-Emitting Diodes. Molecules 2022; 28:molecules28010134. [PMID: 36615328 PMCID: PMC9822092 DOI: 10.3390/molecules28010134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 12/28/2022] Open
Abstract
Solution processes have promising advantages of low manufacturing cost and large-scale production, potentially applied for the fabrication of organic and quantum dot light-emitting diodes (OLEDs and QLEDs). To meet the expected lifespan of OLEDs/QLEDs in practical display and lighting applications, tandem architecture by connecting multiple light-emitting units (LEUs) through a feasible intermediate connection layer (ICL) is preferred. However, the combination of tandem architecture with solution processes is still limited by the choices of obtainable ICLs due to the unsettled challenges, such as orthogonal solubility, surface wettability, interfacial corrosion, and charge injection. This review focuses on the recent progresses of solution-processed tandem OLEDs and tandem QLEDs, covers the design and fabrication of various ICLs by solution process, and provides suggestions on the future challenges of corresponding materials and devices, which are anticipated to stimulate the exploitation of the emerging light technologies.
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Affiliation(s)
- Shu-Guang Meng
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou 215123, China
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou 215123, China
| | - Xiao-Zhao Zhu
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou 215123, China
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou 215123, China
| | - Dong-Ying Zhou
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou 215123, China
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou 215123, China
- Correspondence:
| | - Liang-Sheng Liao
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou 215123, China
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou 215123, China
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38
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Gao Y, Wu S, Shan G, Cheng G. Recent Progress in Blue Thermally Activated Delayed Fluorescence Emitters and Their Applications in OLEDs: Beyond Pure Organic Molecules with Twist D-π-A Structures. MICROMACHINES 2022; 13:2150. [PMID: 36557449 PMCID: PMC9784815 DOI: 10.3390/mi13122150] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 11/26/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Thermally activated delayed fluorescence (TADF) materials, which can harvest all excitons and emit light without the use of noble metals, are an appealing class of functional materials emerging as next-generation organic electroluminescent materials. Triplet excitons can be upconverted to the singlet state with the aid of ambient thermal energy under the reverse inter-system crossing owing to the small singlet-triplet splitting energy (ΔEST). This results from a specific molecular design consisting of minimal overlap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital, due to the spatial separation of the electron-donating and electron-releasing part. When a well-designed device structure is applied, high-performance blue-emitting TADF organic light-emitting diodes can be realized with an appropriate molecular design. Unlike the previous literature that has reviewed general blue-emitting TADF materials, in this paper, we focus on materials other than pure organic molecules with twist D-π-A structures, including multi-resonance TADF, through-space charge transfer TADF, and metal-TADF materials. Cutting-edge molecules with extremely small and even negative ΔEST values are also introduced as candidates for next-generation TADF materials. In addition, OLED structures used to exploit the merits of the abovementioned TADF emitters are also described in this review.
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Affiliation(s)
- Yiting Gao
- State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China
- Institute of Functional Material Chemistry and National & Local United Engineering Lab for Power Battery, Faculty of Chemistry, Northeast Normal University, Changchun 130024, China
| | - Siping Wu
- State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China
| | - Guogang Shan
- Institute of Functional Material Chemistry and National & Local United Engineering Lab for Power Battery, Faculty of Chemistry, Northeast Normal University, Changchun 130024, China
| | - Gang Cheng
- State Key Laboratory of Synthetic Chemistry, Department of Chemistry, The University of Hong Kong, Hong Kong, China
- HKU Shenzhen Institute of Research and Innovation, Shenzhen 518053, China
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39
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He X, Lou J, Li B, Wang H, Peng X, Li G, Liu L, Huang Y, Zheng N, Xing L, Huo Y, Yang D, Ma D, Zhao Z, Wang Z, Tang BZ. An Ultraviolet Fluorophore with Narrowed Emission via Coplanar Molecular Strategy. Angew Chem Int Ed Engl 2022; 61:e202209425. [DOI: 10.1002/anie.202209425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Indexed: 11/19/2022]
Affiliation(s)
- Xin He
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Jingli Lou
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Baoxi Li
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Han Wang
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Xiaoluo Peng
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Ganggang Li
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Lu Liu
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Yu Huang
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Nan Zheng
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Longjiang Xing
- School of Chemical Engineering & Light Industry Guangdong University of Technology Guangzhou 510006 China
| | - Yanping Huo
- School of Chemical Engineering & Light Industry Guangdong University of Technology Guangzhou 510006 China
| | - Dezhi Yang
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Dongge Ma
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Zujin Zhao
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Zhiming Wang
- State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates Center for Aggregation-Induced Emission AIE Institute Guangzhou International Campus South China University of Technology Guangzhou 510640 China
| | - Ben Zhong Tang
- Shenzhen Institute of Aggregate Science and Technology School of Science and Engineering The Chinese University of Hong Kong, Shenzhen Shenzhen 518172 China
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40
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Xie F, Li H, Zhang K, Shen Y, Zhao X, Li Y, Tang J. A Dislocated Twin‐Locking Acceptor‐Donor‐Acceptor Configuration for Efficient Delayed Fluorescence with Multiple Through‐Space Charge Transfer. Angew Chem Int Ed Engl 2022; 61:e202213823. [DOI: 10.1002/anie.202213823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Feng‐Ming Xie
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou Jiangsu 215123 P. R. China
| | - Hao‐Ze Li
- School of Physics and Electronic Science Ministry of Education Nanophotonics & Advanced Instrument Engineering Research Center East China Normal University Shanghai 200062 P. R. China
| | - Kai Zhang
- Macau Institute of Materials Science and Engineering (MIMSE) Faculty of Innovation Engineering Macau University of Science and Technology Taipa Macau SAR 999078 P. R. China
| | - Yang Shen
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou Jiangsu 215123 P. R. China
| | - Xin Zhao
- School of Chemistry and Life Sciences Suzhou University of Science and Technology Suzhou Jiangsu 215009 P. R. China
| | - Yan‐Qing Li
- School of Physics and Electronic Science Ministry of Education Nanophotonics & Advanced Instrument Engineering Research Center East China Normal University Shanghai 200062 P. R. China
| | - Jian‐Xin Tang
- Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University Suzhou Jiangsu 215123 P. R. China
- Macau Institute of Materials Science and Engineering (MIMSE) Faculty of Innovation Engineering Macau University of Science and Technology Taipa Macau SAR 999078 P. R. China
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41
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Zhao Z, Zeng C, Peng X, Liu Y, Zhao H, Hua L, Su S, Yan S, Ren Z. Tuning Intramolecular Stacking of Rigid Heteroaromatic Compounds for High‐Efficiency Deep‐Blue Through‐Space Charge‐Transfer Emission. Angew Chem Int Ed Engl 2022; 61:e202210864. [DOI: 10.1002/anie.202210864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Zhennan Zhao
- State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 P. R. China
| | - Cheng Zeng
- Key Laboratory of Rubber-Plastics Ministry of Education Qingdao University of Science & Technology Qingdao 266042 P. R. China
| | - Xiaomei Peng
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Guangzhou 510640 P. R. China
| | - Yuchao Liu
- Key Laboratory of Rubber-Plastics Ministry of Education Qingdao University of Science & Technology Qingdao 266042 P. R. China
| | - Haisong Zhao
- State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 P. R. China
| | - Lei Hua
- State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 P. R. China
| | - Shi‐Jian Su
- State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices South China University of Technology Guangzhou 510640 P. R. China
| | - Shouke Yan
- State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 P. R. China
- Key Laboratory of Rubber-Plastics Ministry of Education Qingdao University of Science & Technology Qingdao 266042 P. R. China
| | - Zhongjie Ren
- State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 P. R. China
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42
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Li J, Li Z, Liu H, Gong H, Zhang J, Yao Y, Guo Q. Organic molecules with inverted singlet-triplet gaps. Front Chem 2022; 10:999856. [PMID: 36092667 PMCID: PMC9448862 DOI: 10.3389/fchem.2022.999856] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
According to Hund's multiplicity rule, the energy of the lowest excited triplet state (T1) is always lower than that of the lowest excited singlet state (S1) in organic molecules, resulting in a positive singlet-triplet energy gap (ΔE ST). Therefore, the up-converted reverse intersystem crossing (RISC) from T1 to S1 is an endothermic process, which may lead to the quenching of long-lived triplet excitons in electroluminescence, and subsequently the reduction of device efficiency. Interestingly, organic molecules with inverted singlet-triplet (INVEST) gaps in violation of Hund's multiplicity rule have recently come into the limelight. The unique feature has attracted extensive attention in the fields of organic optoelectronics and photocatalysis over the past few years. For an INVEST molecule possessing a higher T1 with respect to S1, namely a negative ΔE ST, the down-converted RISC from T1 to S1 does not require thermal activation, which is possibly conducive to solving the problems of fast efficiency roll-off and short lifetime of organic light-emitting devices. By virtue of this property, INVEST molecules are recently regarded as a new generation of organic light-emitting materials. In this review, we briefly summarized the significant progress of INVEST molecules in both theoretical calculations and experimental studies, and put forward suggestions and expectations for future research.
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Affiliation(s)
- Jie Li
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu, China
| | - Zhi Li
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu, China
| | - Hui Liu
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu, China
| | - Heqi Gong
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu, China
| | - Jincheng Zhang
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu, China
| | - Yali Yao
- School of Physics and Engineering Technology, Chengdu Normal University, Chengdu, China
| | - Qiang Guo
- College of Optoelectronic Engineering, Chengdu University of Information Technology, Chengdu, China
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43
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Zhao Z, Zeng C, Peng X, Liu Y, Zhao H, Hua L, Su SJ, Yan S, Ren Z. Tuning Intramolecular Stacking of Rigid Heteroaromatic Compounds for High‐Efficiency Deep‐blue Through‐Space Charge‐Transfer Emission. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202210864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Zhennan Zhao
- Beijing University of Chemical Technology State Key Laboratory of Chemical Resource Engineering CHINA
| | - Cheng Zeng
- Qingdao University of Science and Technology Key Laboratory of Rubber-Plastics, Ministry of Education CHINA
| | - Xiaomei Peng
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Yuchao Liu
- Qingdao University of Science and Technology Key Laboratory of Rubber-Plastics, Ministry of Education CHINA
| | - Haisong Zhao
- Beijing University of Chemical Technology State Key Laboratory of Chemical Resource Engineering CHINA
| | - Lei Hua
- Beijing University of Chemical Technology State Key Laboratory of Chemical Resource Engineering CHINA
| | - Shi-Jian Su
- South China University of Technology State Key Laboratory of Luminescent Materials and Devices and Institute of Polymer Optoelectronic Materials and Devices CHINA
| | - Shouke Yan
- Beijing University of Chemical Technology State Key Laboratory of Chemical Resource Engineering CHINA
| | - Zhongjie Ren
- Beijing University of Chemical Technology College of Materials Science and Engineering No.15 North 3th Ring East Road 100029 Beijing CHINA
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44
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Li J, Li Z, Liu H, Gong H, Zhang J, Guo Q. Advances in Blue Exciplex–Based Organic Light-Emitting Materials and Devices. Front Chem 2022; 10:952116. [PMID: 35903189 PMCID: PMC9320026 DOI: 10.3389/fchem.2022.952116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 06/03/2022] [Indexed: 11/13/2022] Open
Abstract
Exciplexes possessing thermally activated delayed fluorescence (TADF) characteristics have received much attention in the fields of organic light-emitting materials and devices over the past decade. In general, an exciplex is a physical mixture between a donor (D) with hole transport properties and an acceptor (A) with electron transport characteristics, and the energy difference between the lowest excited singlet state and the lowest excited triplet state is usually fairly small in terms of the long-range charge-transfer process from D to A. In the processes of photoluminescence and electroluminescence, triplet excitons can be converted to singlet excitons through reverse intersystem crossing and then radiate photons to achieve TADF. As a consequence, triplet excitons can be effectively harvested, and the exciton utilization can be significantly enhanced. Up to now, a large number of exciplexes have been developed and applied to organic light-emitting devices. Notably most of them showed green or red emission, while blue exciplexes are relatively few owing to the spectrum characteristics of the large red-shift and broadened emission. In this study, the latest progress of blue exciplex–based organic light-emitting materials and devices is briefly reviewed, and future research is prospected.
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45
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Yang SY, Qu YK, Liao LS, Jiang ZQ, Lee ST. Research Progress of Intramolecular π-Stacked Small Molecules for Device Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2104125. [PMID: 34595783 DOI: 10.1002/adma.202104125] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 07/18/2021] [Indexed: 06/13/2023]
Abstract
Organic semiconductors can be designed and constructed in π-stacked structures instead of the conventional π-conjugated structures. Through-space interaction (TSI) occurs in π-stacked optoelectronic materials. Thus, unlike electronic coupling along the conjugated chain, the functional groups can stack closely to facilitate spatial electron communication. Using π-stacked motifs, chemists and materials scientists can find new ways for constructing materials with aggregation-induced emission (AIE), thermally activated delayed fluorescence (TADF), circularly polarized luminescence (CPL), and room-temperature phosphorescence (RTP), as well as enhanced molecular conductance. Organic optoelectronic devices based on π-stacked molecules have exhibited very promising performance, with some of them exceeding π-conjugated analogues. Recently, reports on various organic π-stacked structures have grown rapidly, prompting this review. Representative molecular scaffolds and newly developed π-stacked systems could stimulate more attention on through-space charge transfer the well-known through-bond charge transfer. Finally, the opportunities and challenges for utilizing and improving particular materials are discussed. The previous achievements and upcoming prospects may provide new insights into the theory, materials, and devices in the field of organic semiconductors.
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Affiliation(s)
- Sheng-Yi Yang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, Jiangsu, 215123, P. R. China
| | - Yang-Kun Qu
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, Jiangsu, 215123, P. R. China
| | - Liang-Sheng Liao
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, Jiangsu, 215123, P. R. China
- Macao Institute of Materials Science and Engineering, Macau University of Science and Technology, Taipa, Macau SAR, 999078, P. R. China
| | - Zuo-Quan Jiang
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, Jiangsu, 215123, P. R. China
| | - Shuit-Tong Lee
- Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou, Jiangsu, 215123, P. R. China
- Macao Institute of Materials Science and Engineering, Macau University of Science and Technology, Taipa, Macau SAR, 999078, P. R. China
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46
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Efficient circularly polarized photoluminescence and electroluminescence of chiral spiro-skeleton based thermally activated delayed fluorescence molecules. Sci China Chem 2022. [DOI: 10.1007/s11426-022-1249-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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47
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Li Q, Wu Y, Cao J, Liu Y, Wang Z, Zhu H, Zhang H, Huang F. Pillararene-Induced Intramolecular Through-Space Charge Transfer and Single-Molecule White-Light Emission. Angew Chem Int Ed Engl 2022; 61:e202202381. [PMID: 35234348 DOI: 10.1002/anie.202202381] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Indexed: 12/15/2022]
Abstract
The fabrication of single-molecule white-light emission (SMWLE) materials has become a highly studied topic in recent years and through-space charge transfer (TSCT) is emerging as an important concept in this field. However, the preparation of ideal TSCT-based SMWLE materials is still a big challenge. Herein, we report a bifunctional pillar[5]arene (TPCN-P5-TPA) with a linear donor-spacer-acceptor structure and aggregation-induced emission (AIE) property. The bulky pillar[5]arene between the donor and acceptor induces a twisted conformation and a non-conjugated structure, resulting in intramolecular TSCT. In addition, the AIE feature and pillar[5]arene cavity endow TPCN-P5-TPA with responsiveness to viscosity and polar guests, by which the TSCT emission is triggered. The combination of blue locally-excited state emission and yellow TSCT emission of TPCN-P5-TPA generates SMWLE. Therefore, we provide a new and versatile strategy for the construction of TSCT-based SMWLE materials.
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Affiliation(s)
- Qi Li
- State Key Laboratory of Chemical Engineering, Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Yitao Wu
- State Key Laboratory of Chemical Engineering, Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Jiajun Cao
- State Key Laboratory of Chemical Engineering, Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Yang Liu
- State Key Laboratory of Chemical Engineering, Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Zeju Wang
- State Key Laboratory of Chemical Engineering, Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Huangtianzhi Zhu
- State Key Laboratory of Chemical Engineering, Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China
| | - Haoke Zhang
- ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou, 311215, China.,MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China.,Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology, Guangzhou, 510640, China
| | - Feihe Huang
- State Key Laboratory of Chemical Engineering, Stoddart Institute of Molecular Science, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China.,ZJU-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou, 311215, China.,Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China
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48
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Cheon HJ, Shin YS, Park NH, Lee JH, Kim YH. Boron-Based Multi-Resonance TADF Emitter with Suppressed Intermolecular Interaction and Isomer Formation for Efficient Pure Blue OLEDs. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2107574. [PMID: 35274463 DOI: 10.1002/smll.202107574] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 02/03/2022] [Indexed: 06/14/2023]
Abstract
Multi-resonance (MR) thermally activated delayed fluorescent (TADF) emitters are highly attractive due to their superior color purity as well as efficient light-harvesting ability from singlets and triplets. However, boron and nitrogen-based MR-TADF emitters suffer from their strong π-π interaction owing to their rigid flat cores. Herein, a boron-based multi-resonance blue TADF emitter with suppressed intermolecular interaction and isomer formation is developed through a simple synthetic process by introducing meta-xylene and meta-phenyphenyl groups to the core. The MR-TADF emitter, mBP-DABNA-Me, shows a narrowband blue emission with a peak at 467 nm, along with full width at half maximum of 28 nm, and photoluminescence quantum yield of 97%. Notably, highly efficient pure blue organic light-emitting diode (OLED) is realized using mBP-DABNA-Me, showing a maximum external quantum efficiency of 24.3% and a stable blue emission with a Commission Internationale de L'Eclairage coordinate of (0.124, 0.140). The color purity of the OLED is maintained at a high doping concentration of over 20%, attributed to the suppressed intermolecular interaction between the MR emitters.
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Affiliation(s)
- Hyung Jin Cheon
- Department of Chemistry and RIGET, Gyeongsang National University, Jinju, 52828, Republic of Korea
| | - Youn-Seob Shin
- Department of Materials Science and Engineering, Inha University, Incheon, 22212, Republic of Korea
| | - Noh-Hwal Park
- 3D Convergence Center, Inha University, Incheon, 22212, Republic of Korea
| | - Jeong-Hwan Lee
- Department of Materials Science and Engineering, Inha University, Incheon, 22212, Republic of Korea
- 3D Convergence Center, Inha University, Incheon, 22212, Republic of Korea
| | - Yun-Hi Kim
- Department of Chemistry and RIGET, Gyeongsang National University, Jinju, 52828, Republic of Korea
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Song X, Zhang K, Guo R, Sun K, Zhou Z, Huang S, Huber L, Reus M, Zhou J, Schwartzkopf M, Roth SV, Liu W, Liu Y, Zhu W, Müller-Buschbaum P. Process-Aid Solid Engineering Triggers Delicately Modulation of Y-Series Non-Fullerene Acceptor for Efficient Organic Solar Cells. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2200907. [PMID: 35315132 DOI: 10.1002/adma.202200907] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/17/2022] [Indexed: 06/14/2023]
Abstract
Volatile solids with symmetric π-backbone are intensively implemented on manipulating the nanomorphology for improving the operability and stability of organic solar cells. However, due to the isotropic stacking, the announced solids with symmetric geometry cannot modify the microscopic phase separation and component distribution collaboratively, which will constrain the promotion of exciton splitting and charge collection efficiency. Inspired by the superiorities of asymmetric configuration, a novel process-aid solid (PAS) engineering is proposed. By coupling with BTP core unit in Y-series molecule, an asymmetric, volatile 1,3-dibromo-5-chlorobenzene solid can induce the anisotropic dipole direction, elevated dipole moment, and interlaminar interaction spontaneously. Due to the synergetic effects on the favorable phase separation and desired component distribution, the PAS-treated devices feature the evident improvement of exciton splitting, charge transport, and collection, accompanied by the suppressed trap-assisted recombination. Consequently, an impressive fill factor of 80.2% with maximum power conversion efficiency (PCE) of 18.5% in the PAS-treated device is achieved. More strikingly, the PAS-treated devices demonstrate a promising thickness-tolerance character, where a record PCE of 17.0% is yielded in PAS devices with a 300 nm thickness photoactive layer, which represents the highest PCE for thick-film organic solar cells.
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Affiliation(s)
- Xin Song
- School of Materials Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Kai Zhang
- School of Materials Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Renjun Guo
- Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München, 85748, Garching, Germany
| | - Kun Sun
- Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München, 85748, Garching, Germany
| | - Zhongxin Zhou
- School of Materials Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Shenglei Huang
- Research Center for New Energy Technology (RCNET), Shanghai Institute of Microsystem and Information technology (SIMIT), Chinese Academy of Science (CAS), Jiading, Shanghai, 201800, China
| | - Linus Huber
- Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München, 85748, Garching, Germany
| | - Manuel Reus
- Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München, 85748, Garching, Germany
| | - Jungui Zhou
- Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München, 85748, Garching, Germany
| | | | - Stephan V Roth
- Deutsches Elektronen-Synchrotron (DESY), 22607, Hamburg, Germany
- Department of Fiber and Polymer Technology, KTH Royal Institute of Technology, Stockholm, 10044, Sweden
| | - Wenzhu Liu
- Research Center for New Energy Technology (RCNET), Shanghai Institute of Microsystem and Information technology (SIMIT), Chinese Academy of Science (CAS), Jiading, Shanghai, 201800, China
| | - Yu Liu
- School of Materials Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Weiguo Zhu
- School of Materials Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Changzhou University, Changzhou, 213164, P. R. China
| | - Peter Müller-Buschbaum
- Lehrstuhl für Funktionelle Materialien, Physik-Department, Technische Universität München, 85748, Garching, Germany
- Heinz Maier-Leibnitz-Zentrum, Technische Universität München, 85748, Garching, Germany
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50
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Lee S, Park CS, Yoon H. Nanoparticulate Photoluminescent Probes for Bioimaging: Small Molecules and Polymers. Int J Mol Sci 2022; 23:4949. [PMID: 35563340 PMCID: PMC9100005 DOI: 10.3390/ijms23094949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 04/26/2022] [Accepted: 04/27/2022] [Indexed: 11/22/2022] Open
Abstract
Recent interest in research on photoluminescent molecules due to their unique properties has played an important role in advancing the bioimaging field. In particular, small molecules and organic dots as probes have great potential for the achievement of bioimaging because of their desirable properties. In this review, we provide an introduction of probes consisting of fluorescent small molecules and polymers that emit light across the ultraviolet and near-infrared wavelength ranges, along with a brief summary of the most recent techniques for bioimaging. Since photoluminescence probes emitting light in different ranges have different goals and targets, their respective strategies also differ. Diverse and novel strategies using photoluminescence probes against targets have gradually been introduced in the related literature. Among recent papers (published within the last 5 years) on the topic, we here concentrate on the photophysical properties and strategies for the design of molecular probes, with key examples of in vivo photoluminescence research for practical applications. More in-depth studies on these probes will provide key insights into how to control the molecular structure and size/shape of organic probes for expanded bioimaging research and applications.
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Affiliation(s)
- Sanghyuck Lee
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Korea;
| | - Chul Soon Park
- Drug Manufacturing Center, Daegu-Gyeongbuk Medical Innovation Foundation (DGMIF), Daegu 41061, Korea;
| | - Hyeonseok Yoon
- Department of Polymer Engineering, Graduate School, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Korea;
- School of Polymer Science and Engineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 61186, Korea
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