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1.
烷基芴与三苯胺取代-3,6-芴共聚物的合成及其性能   总被引:1,自引:1,他引:0  
用Suzuki偶联反应制备了一系列新型的9,9-二辛基-2,7-芴(DOF)与9,9-二(4-二苯胺基苯基)-3,6-芴(36FT)的共聚物. 所有的聚合物均可溶于常见的有机溶剂(如THF, CHCl3和甲苯等), 分子量在47000~189000之间. 电化学研究结果表明, 所有聚合物的HOMO能级都高于均聚烷基芴, 并且随着36FT含量的增加, HOMO值逐渐上升. 以该类聚合物为发光层制作了结构为ITO/PEDOT/PVK/polymer/Ba/Al的器件, 获得了稳定的蓝光发射, 其中以36PFT10为发光层的器件获得了0.52%的最大外量子效率.  相似文献   

2.
为了得到绿色单峰发光的聚合物材料, 我们设计并合成了9位取代的二烯丙基芴单体, 在NiCl2的催化下, 合成了可溶的聚芴衍生物, 聚(9,9-二烯丙基芴)(PAF). 较短的烯丙基链既可以增加聚芴的溶解度, 双键的存在又有利于聚芴发生分子间聚集而得到绿光发射的有机电致发光器件(OLED). PAF在溶液和薄膜状态下的荧光峰分别位于403和456 nm的蓝光区域, 而其器件ITO/PEDOT:PSS/PAF/LiF/Al(其中, ITO为氧化铟锡, PEDOT为聚(3,4-乙撑二氧噻吩), PSS为聚苯乙烯磺酸盐)的电致发光峰却红移至绿光区域(532 nm), 得到绿色单峰发光. 紫外吸收光谱、荧光发射光谱、红外光谱以及原子力显微镜(AFM)图像的结果证明, 造成PAF电致发绿光的机制为聚合物分子间聚集.  相似文献   

3.
制备了有机电致发光材料1,3-二[(4′-特丁基苯基)-(1″,3″-噁二唑-5)]-苯(以下简写作OXD-7),通过核磁共振光谱、红外光谱对其结构进行了表征。利用紫外可见吸收光谱、荧光光谱和循环伏安法等研究了其最高被占用分子轨道(HOMO)及最低空余分子轨道(LUMO)能级及发光性能。OXD-7的HOMO能级为5.24eV,LUMO能级为1.69eV。OXD-7在306nm波长处有一吸收峰。采用300nm的紫外光激发,荧光发射峰值波长为366.6nm。  相似文献   

4.
芴与噻吩发光共聚物的合成及其电致发光性能   总被引:9,自引:2,他引:9  
采用Suzuki偶合方法合成出了一系列新型的 9,9 二辛基芴 (DOF)和噻吩 (Th)的共聚物 .其中 ,DOF与Th的投料比 (摩尔比 )分别为 95∶5 (PTF5 )、90∶1 0 (PTF1 0 )、85∶1 5 (PTF1 5 )、70∶3 0 (PTF3 0 )、5 0∶5 0 (PTF5 0 ) .所有的聚合物均可溶于常用的有机溶剂 ,如THF,CHCl3等 ,其分子量在 60 0 0~ 5 3 0 0 0之间 .当在聚芴主链中引入噻吩后 ,其发光波长发生了红移 ,最大发光波长由PTF5时的 490nm红移到PTF5 0时的 5 41nm .随着聚芴主链中噻吩含量的增加 ,最大电致发光和光致发光效率都逐渐降低 由这些聚合物所制得的器件 ,最大电致发光效率为PTF5和PTF1 0的 0 45 %.由此表明 ,在聚芴主链中引入少量的低带隙单体噻吩可以调节聚芴的发光颜色及发光效率  相似文献   

5.
用Suzuki缩聚反应分别将窄带隙单元-苯并噻二唑-二苯胺(DPABT)和苯并噻二唑-三苯胺(TPABT)引入聚芴主链,合成了共聚物PF-DPABT和PF-TPABT,并比较了共聚物的发光性能.随着窄带隙单元含量的增加,其特征发射逐渐增强,说明发生了从聚合物主体单元到窄带隙单元有效的能量转移.两种共聚物在低窄带隙单元含量(1mol%)下的电致发光光谱仅出现窄带隙单元的特征发射,PF-DPABT共聚物为650~680nm之间的饱和红光,而PF-TPABT共聚物为590~610nm之间的橙红光,聚芴主体单元的发射被完全淬灭,说明与光致发光过程相比,电致发光过程中的能量转移更完全.基于共聚物PF-DPABT-1及PF-TPABT-5器件的最大外量子效率分别为1.3%和2.0%,器件结构为ITO/PEDOT:PSS/polymer/Ba/Al,是一类有希望的红光材料.  相似文献   

6.
通过Suzuki偶合反应合成了一系列胺烷基侧链取代的基于三苯胺和芴的共轭聚合物聚[4-(N,N-二甲基胺丙氧基)苯-4,4′-二苯胺-9,9-二辛基芴-4,7-二噻吩-2-基-2,1,3-苯并噻二唑](PFTD), 并对其化学结构和光电性能进行了表征. 末端胺基的存在提高了此类聚合物作为发光层应用于聚合物电致发光器件的性能(采用高功函数的金属铝作为阴极时). 结构为ITO/PVK/PFTD-5(DBT摩尔分数为5%时的聚合物)/Al的器件最大电致发射峰位于647 nm, 最大外量子效率达到了1.24%.  相似文献   

7.
聚芴是一类重要的蓝光发射材料,有高亮度、高效率等优点;然而聚芴类材料在发光器件中使用一段时间之后,光致发光光谱在530~550 nm、电致发光光谱在2.2~2.3e V的区域出现新的发射带,使得器件的发射变成绿光或蓝绿光,在色度失纯的同时,器件的发光效率也迅速降低.本文概述了目前提出的有关聚芴材料低能级发射形成的原因的假说、试验依据、理论计算、以及基于假说所提出的消除低能级发射、改善材料发射稳定性的方法等研究现状.  相似文献   

8.
设计合成了一种化合物3FPITPA,并对其结构进行表征。通过理论计算发现,该分子的扭曲结构很好的实现了HOMO与LUMO的分离。而通过测试不同溶剂中的发光光谱,发现该分子的发光光谱随着溶剂极性增加而红移,表明其存在分子内电荷转移,分子的偶极矩越大,和溶剂分子作用越大,导致非辐射跃迁能量损失越大,发光红移;通过变温光谱表明其具有热活性延迟荧光的特性;通过热失重和差示量热扫描分析表明其具有良好的热稳定性,其5%失重温度为350℃,玻璃化转变温度为266℃,可通过真空蒸镀制备有机发光器件。以此发光材料制备的有机发光器件,其发射峰波长为610 nm,最大亮度为9447 cd/m2,最大外量子效率为18.3%。  相似文献   

9.
设计并合成了一系列以三苯胺为核,芴衍生物为外围基团的有机蓝光小分子,该合成通过Suzuki反应在9-芳基芴的2位和(或)7位引入相同或不同取代基作为模块,并利用Friedel-Crafts反应将4-甲基三苯胺与这一系列模块结合.用NMR,MS和元素分析进行结构表征.荧光测试结果表明该类化合物溶液的荧光发射波长范围在442~466 nm之间,属蓝光发射.电化学测试显示该类材料的HOMO能级位于-5.15~-5.19 eV之间.差示扫描量热仪与热重分析得出化合物的玻璃化转变温度在166℃以上,热分解温度高于398℃,表明该类材料具有良好的热稳定性.  相似文献   

10.
设计合成了一种新型二苯胺螺芴化合物2,7-双二苯胺-螺环[芴-7,9’-苯并芴](DDsF),通过了1HNMR,MS,IR图谱测试和元素分析,每步反应产率均在70%以上;利用紫外可见吸收光谱、荧光光谱研究了其发光性能.结果表明,在固体状态下,其荧光发射峰红移40 nm左右.然而溶液荧光强度及荧光量子产率都随着溶剂极性的变化有着明显差异;通过循环伏安法测得其氧化峰电位为0.77 V,计算出DDSF的HOMO能级为-5.10 eV,LUMO能级为-2.95 eV.  相似文献   

11.
陈磊  程延祥  谢志元  王利祥 《应用化学》2011,28(11):1229-1238
设计合成了新型的含萘并噻二唑(NT)或苯并硒二唑(BS)电子受体单元的D-A型红光掺杂剂,将它们引入到聚芴(PFO)的主链,调节掺杂剂含量,合成了一系列具有“掺杂剂/主体”特性的红光高分子材料含萘并噻二唑衍生物的聚芴(PFR-xNT)和含苯并硒二唑衍生物的取芴(PFR-xBS)。 这些红光高分子的吸收光谱主要表现为聚芴主体的吸收,荧光光谱既有主体聚芴的蓝光峰,也有掺杂剂的红光峰,并且红光峰的相对强度随着掺杂剂含量的增加而增强。 与光致发光光谱不同,这些高分子的电致发光光谱主要表现为掺杂剂的红光发射,并在掺杂的摩尔分数达到1%时实现了主体聚芴向红光掺杂剂的完全能量转移。 其中PFR-10NT和PFR-10BS的单层器件(ITO/PEDOT:PSS/Polymer/Ca/Al)(PEDOT:聚3,4-乙烯二氧噻吩;PSS:聚苯乙烯磺酸)分别实现了电流效率1.61 cd/A,最大发射波长632 nm,CIE色坐标(0.63,0.35)以及电流效率1.10 cd/A,最大发射波长620 nm,CIE色坐标(0.63,0.36)的高效红光发射。  相似文献   

12.
Several examples of sol–gel preparation of doped materials are taken to illustrate the various situations where the doping elements are responsible for the main function of the material or govern its structure. Other examples are used to illustrate that sometimes unexpected effects can be observed like structural modification and the appearance of new properties. Rare earth doped scintillators demonstrate higher homogeneity for materials prepared via sol–gel chemistry when compared with classical solid state reaction. The XRD study of rare earth doped orthoborates shows that doping can affect the vaterite to calcite phase transition observed in these compounds. A Raman spectroscopic study has been performed on doped silica xerogels and it has been shown that doping ions can modify greatly the densification process in these amorphous materials. Finally, it has been evidenced that sol–gel chemistry allows the preparation of bioactive ceramics with enhanced properties. In particular Zn-doped HAP with anti inflammatory properties has been prepared and Sr-doped bioactive glasses have demonstrated superior in-vitro bioactivity as evidenced by PIXE-RBS study.  相似文献   

13.
Mn‐doped SrMoO4 nanocrystals were synthesized by thermal decomposition of metal–organic salt in an organic solvent with the doping content in the range 0–12 mol%. The structures, morphologies and optical properties were characterized using various techniques. The results suggest that Mo sites in the SrMoO4 lattice are substituted by the Mn dopant, the adsorption bands are found to be shifted toward the visible light region and the band gap becomes narrower correspondingly. The photocatalytic performance of the as‐synthesized product was determined using the degradation of methylene blue by visible light irradiation. The photocatalytic performance is enhanced with Mn doping, and the optimal degradation rate is 85% in 140 min for 5 mol% Mn doping. The enhanced photocatalytic activity with Mn doping may be ascribed to the energy band adjustment and effective photogenerated electron–hole separation caused by the Mn doping. A possible photocatalytic mechanism is also discussed.  相似文献   

14.
Polymer‐solvent compound formation, occurring via co‐crystallization of polymer chains and selected small‐molecular species, is demonstrated for the conjugated polymer poly(9,9‐dioctylfluorene) (PFO) and a range of organic solvents. The resulting crystallization and gelation processes in PFO solutions are studied by differential scanning calorimetry, with X‐ray diffraction providing additional information on the resulting microstructure. It is shown that PFO‐solvent compounds comprise an ultra‐regular molecular‐level arrangement of the semiconducting polymer host and small‐molecular solvent guest. Crystals form following adoption of the planar‐zigzag β‐phase chain conformation, which, due to its geometry, creates periodic cavities that accommodate the ordered inclusion of solvent molecules of matching volume. The findings are formalized in terms of nonequilibrium temperature–composition phase diagrams. The potential applications of these compounds and the new functionalities that they might enable are also discussed. © 2015 The Authors. Journal of Polymer Science Part B: Polymer Physics published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1481–1491  相似文献   

15.
Poly(9,9‐dioctylfluorene) (PFO) is a widely studied blue‐emitting conjugated polymer, the optoelectronic properties of which are strongly affected by the presence of a well‐defined chain‐extended “β‐phase” conformational isomer. In this study, optical and Raman spectroscopy are used to systematically investigate the properties of PFO thin films featuring a varied fraction of β‐phase chain segments. Results show that the photoluminescence quantum efficiency (PLQE) of PFO films is highly sensitive to both the β‐phase fraction and the method by which it was induced. Notably, a PLQE of ~69% is measured for PFO films possessing a ~6% β‐phase fraction induced by immersion in solvent/nonsolvent mixtures; this value is substantially higher than the average PLQE of ~55% recorded for other β‐phase films. Furthermore, a linear relationship is observed between the intensity ratios of selected Raman peaks and the β‐phase fraction determined by commonly used absorption calibrations, suggesting that Raman spectroscopy can be used as an alternative means to quantify the β‐phase fraction. As a specific example, spatial Raman mapping is used to image a mm‐scale β‐phase stripe patterned in a glassy PFO film, with the extracted β‐phase fraction showing excellent agreement with the results of optical spectroscopy. © 2016 The Authors. Journal of Polymer Science Part B: Polymer Physics Published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1995–2006  相似文献   

16.
To determine the optimum conditions for the complete extraction of perfluorooctanoate (PFO) from polytetrafluoroethylene fluoropolymers, sample preparation and pressurized solvent extraction (PSE) conditions were investigated. Solvent extraction temperature, solvent residence time, relaxation time between extractions, and the effects of heating before PSE showed that methanol at 150 degrees C extraction temperature and a 12 min solvent residence time were the most efficient conditions. Preheating the polymer before extraction at 150 degrees C for 24 h significantly enhanced the quantity of PFO removed. Heating above 150 degrees C resulted in loss of PFO. PFO was determined by liquid chromatography with tandem mass spectrometry.  相似文献   

17.
粟智  叶世海  王永龙 《化学学报》2009,67(21):2413-2420
用水热法合成了锂离子电池正极材料正交结构LiMnO2材料, 并对其进行S2-、大尺寸阳离子(Cu2+, Co3+, Ti4+)以及硫-金属离子复合掺杂改性. 用X射线衍射(XRD)、X光电子能谱分析(XPS)、透射电子显微镜(TEM)、恒电流充放电、交流阻抗谱(EIS)等测试技术进行表征. 实验结果表明: 当掺入离子的含量较低时, 得到的产物能保持完整的正交结构, 并表现出较好的电化学性能. S2-和非Jahn-Teller效应大尺寸阳离子的掺入使材料的循环稳定性能大幅度提高, 而这种提高是源于这些离子对LiMnO2结构的稳定作用. 电极材料Li1.02Mn0.988Ti0.012O1.989S0.011显示了最优的电化学性能, 在50 mA•g-1放电速率下, 其初始放电容量为142.6 mAh•g-1, 60次循环后放电容量为213.4 mAh•g-1. 硫-金属阳离子复合掺杂, 综合了大尺寸阳离子可以提高材料中Li+的扩散能力和S2-掺杂抑制Jahn-Teller畸变两方面优势, 使层状结构LiMnO2正极材料既保持了较高的容量又获得良好的循环性能.  相似文献   

18.
Aziridines underwent cyclization reaction with carbon disulfide and isothiocyanate in the presence of organophosphine to afford thiazolidinone derivatives in good to high yields. The mechanistic study revealed that organophosphine serves as a catalyst in the reaction.  相似文献   

19.
We have performed a comparative study of the electronic properties of six different electron-doped metal-phthalocyanine (MPc) compounds (ZnPc, CuPc, NiPc, CoPc, FePc, and MnPc), in which the electron density is controlled by means of potassium intercalation. Despite the complexity of these systems, we find that the nature of the underlying molecular orbitals produces observable effects in the doping dependence of the electrical conductivity of the materials. For all the MPc's in which the added electrons are expected to occupy orbitals centered on the ligands (ZnPc, CuPc, and NiPc), the doping dependence of the conductivity has an essentially identical shape. This shape is different from that observed in MPc materials in which electrons are also added to orbitals centered on the metal atom (CoPc, FePc, and MnPc). The observed relation between the macroscopic electronic properties of the MPc compounds and the properties of the molecular orbitals of the constituent molecules clearly indicates the richness of the alkali-doped metal-phthalocyanines as a model class of compounds for the investigation of the electronic properties of molecular systems.  相似文献   

20.
The number of compounds and doping methods in sports is in a state of constant flux. In addition to ‘traditional’ doping agents, such as anabolic androgenic steroids or erythropoietin, new therapeutics and emerging drugs have considerable potential for misuse in elite sport. Such compounds are commonly based on new chemical structures, and the mechanisms underlying their modes of action represent new therapeutic approaches arising from recent advances in medical research; therefore, sports drug testing procedures need to be continuously modified and complementary methods developed, preferably based on mass spectrometry, to enable comprehensive doping controls. This tutorial not only discusses emerging drugs that can be categorized as anabolic agents (selective androgen receptor modulators, SARMs), gene doping [hypoxia‐inducible factor stabilizers, peroxisome‐proliferator‐activated receptor (PPAR)δ‐agonists] and erythropoietin‐mimetics (Hematide) but also compounds with potentially performance‐enhancing properties that are not classified in the current list of the World Anti‐Doping Agency. Compounds such as ryanodine‐calstabin‐complex modulators (benzothiazepines) are included, their mass spectrometric properties discussed, and current approaches in sports drug testing outlined. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

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