Journal ArticleDOI
Over 10% EQE Near-Infrared Electroluminescence Based on a Thermally Activated Delayed Fluorescence Emitter
Yi Yuan,Yun Hu,Ye-Xin Zhang,Jiu-Dong Lin,Ya-Kun Wang,Zuo-Quan Jiang,Liang-Sheng Liao,Shuit-Tong Lee +7 more
TLDR
In this article, a wedge-shaped Dπ-A-π-D emitter with thermally activated delayed fluorescence property and a small single-triplet splitting (ΔEst) of 0.14 eV is presented.Abstract:
Significant effort has been made to develop novel material systems to improve the efficiency of near-infrared organic light-emitting diodes (NIR OLEDs). Of those, fluorescent chromophores are mostly studied because of their advantages in cost and tunability. However, it is still rare for fluorescent NIR emitters to present good color purities in the NIR range and to have high external quantum efficiency (EQE). Here, a wedge-shaped D-π-A-π-D emitter APDC-DTPA with thermally activated delayed fluorescence property and a small single-triplet splitting (ΔEst) of 0.14 eV is presented. The non-doped NIR device exhibits excellent performance with a maximum EQE of 2.19% and a peak wavelength of 777 nm. Remarkably, when 10 wt% of APDC-DTPA is doped in 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene host, an extremely high EQE of 10.19% with an emission peak of 693 nm is achieved. All these values represent the best result for NIR OLEDs based on a pure organic fluorescent emitter with similar device structure and color gamut.read more
Citations
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Journal ArticleDOI
High-efficiency electroluminescence and amplified spontaneous emission from a thermally activated delayed fluorescent near-infrared emitter
Dae Hyeon Kim,Anthony D'Aléo,Anthony D'Aléo,Xian Kai Chen,Atula D.S. Sandanayaka,Dandan Yao,Li Zhao,Takeshi Komino,Elena Zaborova,Gabriel Canard,Youichi Tsuchiya,E. Y. Choi,Jeong Weon Wu,Frédéric Fages,Jean-Luc Brédas,Jean Charles Ribierre,Chihaya Adachi +16 more
TL;DR: In this paper, the authors reported thermally activated delayed fluorescent organic light-emitting diodes that operate at near-infrared wavelengths with a maximum external quantum efficiency of nearly 10% using a boron difluoride curcuminoid derivative.
Journal ArticleDOI
Near-Infrared (NIR) Organic Light-Emitting Diodes (OLEDs): Challenges and Opportunities
Journal ArticleDOI
Precise Molecular Design for High-Performance Luminogens with Aggregation-Induced Emission
Shidang Xu,Yukun Duan,Bin Liu +2 more
TL;DR: The useful principles and emerging structure–property relationships for precise molecular design toward AIEgens with desirable properties using concrete examples are revealed and their excellent performance in enabling new research directions in biomedical theranostics, optoelectronic devices, stimuli‐responsive smart materials, and visualization of physical processes are highlighted.
Journal ArticleDOI
Deep‐Red to Near‐Infrared Thermally Activated Delayed Fluorescence in Organic Solid Films and Electroluminescent Devices
Chenglong Li,Ruihong Duan,Baoyan Liang,Guangchao Han,Shipan Wang,Kaiqi Ye,Yu Liu,Yuanping Yi,Yue Wang +8 more
TL;DR: A strategy was developed to construct TADF organic solid films with strong DR or NIR emission feature and the high doped concentration and neat films exhibited efficient DR and NIR emissions, respectively.
Journal ArticleDOI
Highly Efficient Thermally Activated Delayed Fluorescence via J-Aggregates with Strong Intermolecular Charge Transfer.
TL;DR: A novel design strategy is reported for realizing highly efficient thermally activated delayed fluorescence materials via J-aggregates with strong intermolecular charge transfer (CT), which significantly decreases the energy gap between the lowest singlet and triplet excited states to induce high-efficiency TADF even in the NIR region.
References
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Bipolar Phenanthroimidazole Derivatives Containing Bulky Polyaromatic Hydrocarbons for Nondoped Blue Electroluminescence Devices with High Efficiency and Low Efficiency Roll-Off
Yi Yuan,Jia-Xiong Chen,Feng Lu,Qing-Xiao Tong,Qingdan Yang,Hin-Wai Mo,Tsz-Wai Ng,Fu-Lung Wong,Zhengqing Guo,Jun Ye,Zhan Chen,Xiaohong Zhang,Chun-Sing Lee +12 more
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Journal ArticleDOI
Efficient and Tunable Thermally Activated Delayed Fluorescence Emitters Having Orientation‐Adjustable CN‐Substituted Pyridine and Pyrimidine Acceptor Units
Kuan-Chung Pan,Shu-Wei Li,Yu-Yi Ho,Yi-Jiun Shiu,Wei-Lung Tsai,Min Jiao,Wei-Kai Lee,Chung-Chih Wu,Chin-Lung Chung,Tanmay Chatterjee,Yung-Shin Li,Ken-Tsung Wong,Hu Hung-Chieh,Chung-Chia Chen,Meng-Ting Lee +14 more
TL;DR: A series of twisted Dπ-A type emitters based on the acridine donor unit and CN-substituted pyridine, pyrimidine, and benzene acceptor units are studied in this paper.
Journal ArticleDOI
Highly Efficient Solid-State Near-Infrared Emitting Material Based on Triphenylamine and Diphenylfumaronitrile with an EQE of 2.58% in Nondoped Organic Light-Emitting Diode
Xiao Han,Qing Bai,Liang Yao,Haichao Liu,Yu Gao,Jinyu Li,Liqun Liu,Yulong Liu,Xiaoxiao Li,Ping Lu,Bing Yang +10 more
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Journal ArticleDOI
Single-step triplet-triplet annihilation: an intrinsic limit for the high brightness efficiency of phosphorescent organic light emitting diodes.
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Journal ArticleDOI
Rational Design of Charge-Neutral, Near-infrared-Emitting Osmium(II) Complexes and OLED Fabrication
Tsang-Chi Lee,Jui-Yi Hung,Yun Chi,Yi-Ming Cheng,Gene-Hsiang Lee,Pi-Tai Chou,Chung-Chia Chen,Chih-Hao Chang,Chung-Chih Wu +8 more
TL;DR: In this paper, a series of charge neutral Os(II) isoquinolyl triazolate complexes with both trans and cis arrangement of phosphine donors are synthesized, and their structural, electrochemical and photophysical properties are established.