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
A rational design strategy for red thermally activated delay fluorescence emitter employing 2,1,3-benzothiadiazole skeleton with asymmetric structure
TL;DR: In this paper, a red TADF-based organic light-emitting diodes (OLEDs) employing thermally activated delayed fluorescence (TADF) can effectively utilize triplet excitons without the noble-metal doping.
Journal ArticleDOI
13.2% EQE near-infrared TADF OLED with emission peak at 761 nm
Jing-Wen Tai,Yukun Tang,Kai Zhang,Chen Yang,Ze-Hui Pan,Yu-Cheng Lin,Yu-Wei Shih,Chia-Hsun Chen,Tien-Lung Chiu,Jiun-Haw Lee,Chuan-Kui Wang,Chung-Chih Wu,Jianuo Fan +12 more
TL;DR: In this paper , two Y-shaped NIR TADF molecules (Py-TPA and Py-CN)-were introduced, and the inclusion of pyridine unit in these two emitters not only extended the conjugated system but also increased the molecular aspect ratios, thereby leading to their high horizontal ratio of emitting dipole orientation.
Journal ArticleDOI
Recent Progress of Novel Organic Near‐Infrared‐Emitting Materials
TL;DR: In this paper , the design and crystal engineering for novel organic near-infrared (NIR) emissive materials are urgently studied and explored, and a new insight into the fine design and synthesis of the desired organic NIR emitters is provided.
Journal ArticleDOI
Deep-blue thermally activated delayed fluorescence materials with high glass transition temperature
Xiang-Dong Zhu,Qi-Sheng Tian,Qi Zheng,Ya-Kun Wang,Yi Yuan,Yun Li,Zuo-Quan Jiang,Liang-Sheng Liao +7 more
TL;DR: In this article, two thermally activated delayed fluorescence (TADF) deep-blue emitters (4-SCZ, 4SCZ-F) were developed by combining a novel spiro-type donor moiety with different triazine-based unit.
Journal ArticleDOI
Positive isotope effect in thermally activated delayed fluorescence emitters based on deuterium-substituted donor units
Jin-Feng Cheng,Liang-Sheng Liao,Andreas Pretzel,Fan-Cheng Kong,Kai Zhang,Jia-Heng Cai,Yue Zhao,Chuan-Kui Wang,Jian Fan,Jian Fan,Liang-Sheng Liao,Liang-Sheng Liao +11 more
TL;DR: In this article, two deuterium-substituted delayed fluorescence (TADF) emitters, TPAAP-D and TPAAQ-D, have been designed and synthesized to investigate the isotope effect in TADF.
References
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Journal ArticleDOI
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
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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
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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.