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591.
合成了两种新型稀土配合物[Tb(m-MBA)3phen]2·2H2O和TbY(m-MBA)6(phen)2·2H2O, 将其掺杂到导电聚合物PVK中用于有机电致发光器件的发光层, 这样改善了配合物的成膜特性和导电性质. 用这种搀杂体系分别制作了单层发光器件和以AlQ为电子传输层的双层器件. 研究了这些单、双层器件的电致发光性能, 对比了以[Tb(m-MBA)3phen]2·2H2O为发光层的双层器件和以TbY(m-MBA)6(phen)2·2H2O为发光层的器件, 发现后者效率更高, 为0.88 cd·A-1, 其最大亮度为123 cd·m-2. 相似文献
592.
Dongge Ma Xiaojiang Zhao Zhiyong Hong Daike Wang Xiabin Jing Fosong Wang 《中国科学B辑(英文版)》1998,41(3):272-277
Copolymers containing alternating flexible aliphatic blocks and rigid poly (p-phenylenevinylene) (PPV) blocks were synthesized and characterized. It was found that the fluorescent intensity increases
with increasing length of the flexible blocks. Bright blue-light emitting diodes were fabricated using PPV copolymers as electroluminescent
layers. The devices show 190 cd/m2 light-emitting brightness at 460 nm and 15 V turn-on voltage. The effects of oxadiawle derivative PBD and tris(8-hydroxyquinoline)
aluminum Alq3 electron-transporting layers on the luminance and stability of the devices are discussed.
Project supported by the National Natural Science Foundation of China, PCLCC, the State Comission of Science and Technology
of China (863-715-002-0130) and the Chinese Acadeny of Sciences (KJ951-A1-501-01) 相似文献
593.
Electroluminescent properties of three ternary europium complexes with different phenanthroline derivatives 总被引:2,自引:0,他引:2
BIAN Zuqiang GAO Deqing GUAN Min XIN Hao LI Fuyou HUANG Chunhui WANG Kezhi & JIN Linpei . State Key Laboratory of Rare Earth Materials Chemistry Applications Peking University Beijing China . Department of Chemistry Beijing Normal University Beijing China 《中国科学B辑(英文版)》2004,47(4):326-334
In the past decade a number of lanthanide com-plexes have been designed and synthesized for organic electroluminescent (EL) devices owing to their ex-tremely sharp emission bands and potentially high internal quantum efficiency[113]. This characteristic made the lanthanide complexes one kind of promising candidates for full color flat-panel displays which re-quire pure red, green and blue emissions. So far, how-ever, the devices based on lanthanide complexes as emitters have not demonstrated v… 相似文献
594.
以1,4-二(2-氰基-2-苯乙烯基)-2,5-二苯基苯(CNDPDSB)为发光层, N,N'-[3-萘基]-N,N'-二苯基[1,1'-二苯基]-4,4'-二胺(NPB)为空穴传输层, 8-羟基喹啉铝(Alq)为电子传输层, 制备了一种色度稳定的有机电致白光器件. 该器件的白光发射是由CNDPDSB与NPB界面形成的激基复合物发出的红光以及NPB与CNDPDSB发射的蓝光混合而成. 该白光器件的光谱稳定, 在工作电压(6~13 V)内, 色坐标由(0.33, 0.34)变化到(0.31, 0.37). 器件在6 V电压下开启, 10 V电压下的亮度和效率分别为1200 cd/m2和0.2 cd/A. 相似文献
595.
取代基对4-N,N-二苯胺基均二苯乙烯类电致发光材料光电特性的影响 总被引:10,自引:0,他引:10
用紫外吸收光谱、荧光发射光谱、循环伏安法(CV)、微分脉冲伏安法(DPV)等手段研究了4个4-N,N-二苯胺基均二苯乙烯类化合物的光电性能, 计算出它们的电离势(PI)在5.70~5.90 eV, 带隙值(Eg)在2.78~2.88 eV, 分析了电化学行为, 讨论了取代基对吸收光谱、发射光谱和电子结构的影响. 结果表明, 引入供电子基团OCH3后, 分子氧化电位降低, HOMO能量升高, 电离势降低; 引入吸电子基团—Cl后, 氧化电位升高, LUMO能量降低, 电子亲和势增加. 取代基—Cl和—OCH3都使化合物的带隙(Eg)减小, 紫外-可见光谱的吸收峰和荧光光谱的发射峰均发生红移. 相似文献
596.
Yingliang Liu Jianghui Li Huayu Cao Bo Qu Zhijian Chen Qihuang Gong Shengang Xu Shaokui Cao 《先进技术聚合物》2006,17(6):468-473
Several conjugated polymers containing phenothiazine moieties in the main chain were synthesized by Knovenagel or Wittig condensations. The polymers were identified and characterized by 1H‐NMR, IR, gel permeation chromatography (GPC), thermogravimetric analysis (TGA), UV‐vis and fluorescent (FL) spectra. Results indicated that the m‐polymer, which was prepared from the polycondensation of N‐octyl‐3,7‐diformylphenothiazine with m‐phenylene diacetonitrile, is the most thermally stable one in all the polymers synthesized. While, the p‐polymer, which was prepared from the polycondensation of N‐octyl‐3,7‐diformylphenothiazine with p‐phenylene diacetonitrile, is the most thermally instable one. The introduction of a cyano group made the absorption and emissive maxima red‐shift from 429 and 537 nm for the Ph‐polymer to 465 and 597 nm for the p‐polymer respectively. The quinoid structure formation allows the p‐polymer to have a lower band gap than any other polymers. Emissive spectra of all these polymers in tetrahydrofuran (THF) solution have a narrow half‐peak width. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
597.
Guo-liTu ZeLiu Li-xiangWang Dong-geMa Xia-binJing Fo-songWang Hong-binWu Jun-biaoPeng YongCao 《高分子科学》2004,(4):395-398
A new kind of polyfluorene containing oxadiazole as the side chain was synthesized. The introduction of oxadiazole moiety as more bulky group prevents the aggregation and reduces the crystallinity of the polymers. Efficient intramolecular energy transfer from oxadiazole moiety to the conjugated backbone has been realized, leading to 70% improvement of photoluminescence quantum efficiency of the designed polymers. Compared with PAF, the PFOXD exhibits significant improvement in electroluminescence properties, with luminous efficiency of 0.8 cd/A and maximum luminance of 1800cd/m^2, 相似文献
598.
含咔唑基团的新颖Re(Ⅰ)配合物的合成、表征和光电性质的研究 总被引:1,自引:2,他引:1
合成了一种含咔唑基团的新颖配合物Re(CO)_3CLL[L=1-乙基-2-(N-乙基-咔唑 并-4-)咪唑并[4.5-f]1,10-邻菲咯啉],通过元素分析、红外光谱、紫外光谱、~1H NMR、荧光光谱和循环伏安学对其进行了表征,制备了基于真空沉积膜的双层电致 发光器件:ITO/TPD (30 nm)/Re(Co)_3CLL (10 nm)/Mg_(0.9)Ag_(0.1) (110 nm) /Ag(60 nm)该器件启动电压为5V,在电压为9V时达到最大亮度113cd/m~2,发出桔 红色的光。 相似文献
599.
Sarada P. Mishra Akshaya K. Palai Ritu Srivastava Modeeparampil N. Kamalasanan Manoranjan Patri 《Journal of polymer science. Part A, Polymer chemistry》2009,47(23):6514-6525
A series of new low band gap π‐conjugated polymers containing N‐alkyldithieno[3,2‐b:2′,3′‐d]pyrrole, benzo[c][1,2,5]thiadiazole, and alkylthiophenes are reported. The polymerization condition was standardized and the use of CuO to obtain high‐molecular‐weight polymer was also realized. The molecular weight of the polymers was found to be in the range of 45,000–53,000. All the polymers were found to be soluble in most of the common organic solvents, such as chloroform, dichloromethane, THF, and chlorobenzene with excellent film forming properties. The λmax of the polymers was found to be in the range of 687–663 nm with band gap in the range of 1.35–1.43 eV. The oxidation potential of the polymers from cyclic voltammetry was determined to be 0.5–0.75 V. The HOMO levels of the above synthesized polymers were found to be between 5.24 and 5.54 eV. All the polymers exhibited a PL emission in between 755 and 773 nm. The polymers were found to be thermally stable above 277 °C with only a 5% weight loss. From the thermal stability values, it is expected that the current set of polymers are stable enough for the application in electronic devices. To realize the potential use of the polymers, EL devices were fabricated and found to show red emission with comparatively low threshold voltage. A brightness of 54 cd m−2 for the device with polymer PC could be reached. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6514–6525, 2009 相似文献
600.
L. Y. Yang C. Wang L. Q. Li S. Janietz A. Wedel Y. L. Hua S. G. Yin 《Journal of polymer science. Part A, Polymer chemistry》2007,45(18):4291-4299
PPV‐based copolymers containing phenothiazine‐5‐oxide and phenothiazine‐5, 5‐dioxide moieties have been successfully synthesized by Wittig‐Horner reaction and characterized by means of UV‐vis, photoluminescence, electroluminescence spectra, and cyclic voltammetry. All of these copolymers can be dissolved in common organic solvents such as chloroform, tetrahydrofuran, and toluene. The PL maxima in the film state are located at 582, 556, and 552 nm for P1, P2, and P3, respectively. The HOMO and LUMO levels of P2 are found to be ?5.21 and ?2.68 eV, respectively; whereas those of P3 are found to be ?5.26 and ?2.71 eV, respectively. The cyclic voltammetry result indicates that the conversion of electron‐donating sulfide to electron‐withdrawing sulfoxide or sulfone group in polymers plays a dominating role in increasing its oxidation potential. Yellowish‐green light ranging from 568 to 540 nm was observed for the single layer device with the configuration of ITO/Polymer/Ca/Al. Double layer devices with Zn (BTZ)2 as a hole blocking layer exhibited enhanced EL performance compared to the single layer devices. The maximum brightness of the double layer devices of P1, P2, and P3 is 278, 400, and 796 cd/m2, respectively. The results of EL and electrochemical analyses revealed that they are promising candidate materials for organic, light‐emitting diodes with hole‐transporting ability. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4291–4299, 2007 相似文献