- Dimers with thermally activated delayed fluorescence (TADF) emission in non-doped device
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Two novel TADF molecules, with donor#1-σ-donor#2-π-acceptor (D1-σ-D2-π-A) conformation, were designed and synthesized through-bond charge transfer (TBCT) and through-space charge transfer (TSCT). These two materials differ only in the D1 groups with triphenylamine forSFCCNand 10-phenyl-10H-phenoxazine forSFCCNO. Due to the unconjugated linkage, both materials showed very similar emission to that from D2-π-A TBCT effect in dilute solution.SFCCNOcan form dimers at the aggregation state and exhibit intermolecular D1/A TSCT emission because of the planar D1 conformation. Therefore, a non-doped device based onSFCCNOexhibited efficiencies of 12.9% at 100 cd m?2and 10.4% at 1000 cd m?2, which are much higher than theSFCCNbased device.
- Chen, Xing,Khan, Aziz,Zou, Sheng-Nan,Li, Yun,Tian, Qi-Sheng,Zhong, Cheng,Fung, Man-Keung,Jiang, Zuo-Quan,Liao, Liang-Sheng
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- Spiro-type host materials with rigidified skeletons for RGB phosphorescent OLEDs
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A universal host material for red, green and blue phosphors raises challenges for the fabrication of efficient phosphorescent organic light-emitting diodes (PHOLEDs). Herein, two spiro host materials, namely 3-(4,6-diphenyl-1,3,5-triazin-2-yl)-9′,9′-dimethyl-9′H-spiro[fluorene-9,5′-quinolino[3,2,1-de]acridine] (QAF-TRZ) and 3′-(4,6-diphenyl-1,3,5-triazin-2-yl)-10-phenyl-10H-spiro[acridine-9,9′-fluorene] (STF-TRZ), are designed and synthesized. The designed strategy is more appropriate and rarely found among the reported spiro-based skeletons for organic light-emitting diodes (OLEDs). Both materials exhibited excellent electroluminescence performance. In particular, the RGB three-color PHOLEDs based onQAF-TRZandSTF-TRZas hosts and FIrpic, Ir(ppy)2acac, and Ir(MDQ)2acac as emitters are fabricated. The blue PHOLEDs based onQAF-TRZrealize a maximum external quantum efficiency (EQE) of 19.4%, and remain 17.2% at 1000 cd m?2. On the other hand, green PHOLEDs show maximum EQEs of 21% and 19% forQAF-TRZandSTF-TRZ, respectively, and both devices exhibit low efficiency roll-off. The red devices obtain EQEs of 22.6% and 19.4% based onQAF-TRZandSTF-TRZ, respectively, in which the former has among the most efficient value. Consequently, these results confirm that host materials incorporating the spiro-motif with sufficiently high triplet energy are promising for obtaining high performance RGB-based PHOLEDs. The better device performance based onQAF-TRZstems from its better hole transport capability, resulting in a superior charge recombination efficiency.
- Chen, Xing,Fung, Man-Keung,Jiang, Zuo-Quan,Khan, Aziz,Kumar, Sarvendra,Liao, Liang-Sheng,Luo, Wei,Yang, Sheng-Yi,Yu, You-Jun
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- Control of conjugation degree via position engineering to highly efficient phosphorescent host materials
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The C3 meta-position of fluorene is utilized to construct high-triplet energy compounds. Incorporating a spiroacridine structure, two new host materials SAFDPA and SAFCz were facilely obtained. Their thermal and photophysical properties are fully investigated. The best efficiencies of 19.4%/21.5% of blue/white devices are achieved by SAFCz.
- Zhang, Ye-Xin,Zhang, Lei,Cui, Lin-Song,Gao, Chun-Hong,Chen, Hua,Li, Qian,Jiang, Zuo-Quan,Liao, Liang-Sheng
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- Novel compound and organic light emitting device comprising the same
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The present invention provides a novel compound and an organic light emitting device using the same. The present invention provides a compound represented by chemical formula 1. The compound represented by the chemical formula 1 can be used as a material for an organic layer of the organic light emitting device, and can improve efficiency, lower driving voltage, and/or improve lifespan characteristics in the organic light emitting device.
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- Compound for organic electroluminescent device, and application thereof
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The invention relates to a compound for an organic electroluminescent device. The structure of the compound is shown as a formula (I), in the formula, R1-R6 are respectively and independently selected from a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group and a substituted or unsubstituted heteroaryl group. The compound disclosed by the invention is of a boron main body structure, and the boron element is easier to form a structure with an electronic defect characteristic than the carbon element, so that the derivative of the compound has relatively good electron withdrawing capability. In addition, a spirofluorene unit with the characteristic of good thermal stability is introduced into a boron structural unit, so that the bipolar boron compound with high triplet energy can be obtained; besides, the compound contains a stable multi-element ring structure, so that the stability of the material is greatly improved, the molecular weight is relatively large, and the glass-transition temperature of the material is increased, thereby ensuring that the material is not decomposed after being evaporated for a long time.
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Paragraph 0024-0025
(2021/07/24)
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- The Control of Conjugation Lengths and Steric Hindrance to Modulate Aggregation-Induced Emission with High Electroluminescence Properties and Interesting Optical Properties
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A series of novel AIE-active (aggregation-induced emission) molecules, named SAF-2-TriPE, SAF-3-TriPE, and SAF-4-TriPE, were designed and synthesized through facile reaction procedures. We found that incorporation of the spiro-acridine-fluorene (SAF) group, which is famous for its excellent hole-transporting ability and rigid structure, at different substitution positions on the phenyl ring affected the conjugation lengths of these compounds. Consequently, we have obtained molecules with different emission colors and properties without sacrificing good EL (electroluminescence) characteristics. Accordingly, a device that was based on compound SAF-2-TriPE displayed superior EL characteristics: it emitted green light with ηc, max=10.5 cd A-1 and ηext, max=4.22 %, whereas a device that was based on compound SAF-3-TriPE emitted blue-green light with ηc, max=3.9 cd A-1 and ηext, max= 1.71 %. These compounds also displayed different AIE performances: when the fraction of water in the THF solutions of these compounds was increased, we observed a significant improvement in the ΦF of compounds SAF-2-TriPE and SAF-3-TriPE; in contrast, compound SAF-4-TriPE showed an abnormal phenomenon, in that it emitted a strong fluorescence in both pure THF solution and in the aggregated state without a significant change in ΦF. Overall, this systematic study confirmed a relationship between the regioisomerism of the luminophore structure and its AIE activity and the resulting electroluminescent performance in non-doped devices. Luminophores for organic LEDs: A series of new molecules, named SAF-2-TriPE, SAF-3-TriPE, and SAF-4-TriPE, that contain a quasi-TPE (tetraphenylethene) subunit, were developed (see figure). These compounds displayed typical aggregation-induced emission (AIE) properties, with the exception of the more weakly emitting SAF-4-TriPE. Additionally, non-doped devices based on luminogens SAF-2-TriPE, SAF-3-TriPE, and SAF-4-TriPE were fabricated, and they displayed different electroluminescence properties with quantum efficiencies of 4.22, 1.71, and 1.42 %, respectively.
- Xue, Miao-Miao,Xie, Yue-Min,Cui, Lin-Song,Liu, Xiang-Yang,Yuan, Xiao-Dong,Li, Yong-Xi,Jiang, Zuo-Quan,Liao, Liang-Sheng
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p. 916 - 924
(2016/01/16)
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- COMPOUND AND ORGANIC LIGHT EMITTING DEVICE COMPRISING THE SAME
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The present invention relates to a compound and an organic light-emitting device comprising the same. The compound is represented by chemical formula 1. According to an embodiment of the present invention, the compound can be used as a material of an organic matter layer of an organic light-emitting device.COPYRIGHT KIPO 2016
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Paragraph 0218; 0225; 0226
(2017/03/23)
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- The study on two kinds of spiro systems for improving the performance of host materials in blue phosphorescent organic light-emitting diodes
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The introduction of spiro-acridine-fluorene (SAF) can affect the electronic structure of the whole molecule, which made SAF-based materials exhibit totally different photophysical properties from conventional spirobifluorene-based materials. With these pr
- Liu, Xiang-Yang,Liang, Feng,Ding, Lei,Dong, Shou-Cheng,Li, Qian,Cui, Lin-Song,Jiang, Zuo-Quan,Chen, Hua,Liao, Liang-Sheng
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p. 9053 - 9056
(2015/09/08)
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- Spiro-annulated triarylamine-based hosts incorporating dibenzothiophene for highly efficient single-emitting layer white phosphorescent organic light-emitting diodes
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Four novel host materials were designed and synthesized, incorporating fluorene-spiro-annulated triphenylamine-carbazole (ST-SCz) and dibenzothiophene (DBT) blocks. A meta-linking strategy was applied by introducing DBT moieties to ST-SCz skeletons at the C3 position of the fluorene backbones. As expected, high triplet energies (over 2.80 eV) were achieved in all four materials despite the different linking positions on the DBT. All four materials show a high Tg from 149 to 163 °C, which benefits from their spiro-structure. Their thermal, electrochemical and photo-physical properties were fully characterized. Highly efficient blue and white PHOLEDs were fabricated using these four materials as the hosts. Triphenylamine-containing STDBT4 and STDBT2 demonstrate better device performance due to their relatively high-lying HOMO compared to carbazole-containing SCzDBT4 and SCzDBT2. Maximum ηext of 19.6% and 18.4% (STDBT4 and STDBT2) were achieved for FIrpic-based devices, and 23.7% and 22.2% (STDBT4 and STDBT2) were achieved for two color-based white PHOLEDs with double emitting layers, using PO-01 as a yellow dopant. Finally, a highly efficient single-emitting layer white PHOLED with maximum efficiencies of 24.0%, 77.0 cd A-1 and 63.2 lm W -1 and CIE coordinates of (0.38, 0.48) was realized using the device configuration of ITO/HAT-CN/TAPC/STDBT4: 8 wt% FIrpic: 0.8 wt% PO-01/TmPyPB/Liq/Al. The device shows good color stability and low efficiency roll-off. Even at a high luminance of 10,000 cd m-2, it still maintains very high efficiencies of 17.9%, 56.4 cd A-1 and 26 lm W-1.
- Dong, Shou-Cheng,Liu, Yuan,Li, Qian,Cui, Lin-Song,Chen, Hua,Jiang, Zuo-Quan,Liao, Liang-Sheng
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p. 6575 - 6584
(2013/10/21)
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