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
Near-Infrared Emitting Materials via Harvesting Triplet Excitons: Molecular Design, Properties, and Application in Organic Light Emitting Diodes
Youming Zhang,Youming Zhang,Yafei Wang,Jun Song,Junle Qu,Buhong Li,Weiguo Zhu,Wai Yeung Wong,Wai Yeung Wong +8 more
Journal ArticleDOI
Highly Efficient Thermally Activated Delayed Fluorescence via an Unconjugated Donor–Acceptor System Realizing EQE of Over 30%
Chen-Chen Peng,Sheng-Yi Yang,Hong-Cheng Li,Guohua Xie,Lin-Song Cui,Sheng-Nan Zou,Cyril Poriel,Zuo-Quan Jiang,Liang-Sheng Liao,Liang-Sheng Liao +9 more
TL;DR: This work provides a novel strategy to address the imperious demands for OLEDs with high EQE and low roll-off, by synthesizing two novel thermally activated delayed fluorescence emitters for high-efficiency organic light-emitting diodes.
Journal ArticleDOI
Recent breakthroughs in thermally activated delayed fluorescence organic light emitting diodes containing non-doped emitting layers
TL;DR: In this article, a review of non-doped thermally activated delayed fluorescence (TADF) emitters is presented, which are able to achieve state-of-the-art performance in the field of organic light-emitting diodes (OLEDs).
Journal ArticleDOI
Realizing Record-High Electroluminescence Efficiency of 31.5 % for Red Thermally Activated Delayed Fluorescence Molecules
Zheyi Cai,Xing Wu,Hao Liu,Jingjing Guo,Dezhi Yang,Dongge Ma,Zujin Zhao,Ben Zhong Tang,Ben Zhong Tang +8 more
TL;DR: T tailor-made red TADF molecules comprised of an electron-withdrawing pyrazino[2,3-f][1,10]phenanthroline-2, 3-dicarbonitrile core and various electron-donating triarylamines are developed, which can form intramolecular hydrogen-bonding, conducive to improving emission efficiency and promoting horizontal orientation by increasing molecular rigidity and planarity.
Journal ArticleDOI
A Simple Molecular Design Strategy for Delayed Fluorescence toward 1000 nm.
Daniel G. Congrave,Bluebell H. Drummond,Patrick J. Conaghan,Haydn Francis,Saul T. E. Jones,Clare P. Grey,Neil C. Greenham,Dan Credgington,Hugo Bronstein +8 more
TL;DR: By abandoning the common polydonor model in favor of a D–A dyad structure, a sufficiently strong D-A interaction can be obtained to realize a TADF emitter capable of photoluminescence close to 1000 nm, and this strategy is both conceptually and synthetically simple.
References
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Highly efficient organic light-emitting diodes from delayed fluorescence
Hiroki Uoyama,Kenichi Goushi,Kenichi Goushi,Katsuyuki Shizu,Hiroko Nomura,Chihaya Adachi,Chihaya Adachi +6 more
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Journal ArticleDOI
Sky-Blue Organic Light Emitting Diode with 37% External Quantum Efficiency Using Thermally Activated Delayed Fluorescence from Spiroacridine-Triazine Hybrid.
Ting-An Lin,Tanmay Chatterjee,Wei-Lung Tsai,Wei-Kai Lee,Meng-Jung Wu,Min Jiao,Kuan-Chung Pan,Chih-Lung Yi,Chin-Lung Chung,Ken-Tsung Wong,Chung-Chih Wu +10 more
TL;DR: Extremely efficient sky-blue organic electroluminescence with external quantum efficiency of ≈37% is achieved in a conventional planar device structure using a highly efficient thermally activated delayed fluorescence emitter based on the spiroacridine-triazine hybrid.
Journal ArticleDOI
Anthraquinone-Based Intramolecular Charge-Transfer Compounds: Computational Molecular Design, Thermally Activated Delayed Fluorescence, and Highly Efficient Red Electroluminescence
Qisheng Zhang,H. Kuwabara,William J. Potscavage,Shuping Huang,Yasuhiro Hatae,Takumi Shibata,Chihaya Adachi +6 more
TL;DR: It is demonstrated that increasing the distance between donor (D) and acceptor (A) in intramolecular-charge-transfer molecules is a promising strategy for simultaneously achieving small ΔE(ST) and large k(F), which is in good agreement with those predicted by corrected time-dependent density functional theory.
Journal ArticleDOI
Near‐Infrared Organic Compounds and Emerging Applications
Gang Qian,Zhi Yuan Wang +1 more
TL;DR: This Focus Review describes the emerging class of near-infrared (NIR) organic compounds containing the conjugated polyene, polymethine, and donor-acceptor chromophores and exploration of their NIR-absorbing, Nir-fluorescence, and N IR-photosensitizing properties for potential applications in heat absorbers, solar cells, andNIR light-emitting diodes.