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聚集诱导发光体系:化合物种类、发光机制及其应用 总被引:1,自引:0,他引:1
聚集诱导发光(AIE)体系是近年来备受关注的一个研究领域,目前该领域已经积累了较为丰富的AIE化合物的分子设计理念和相应的对AIE机制的理解。AIE体系的研究为固态强发光材料特别是备受聚集发光猝灭难题困扰的有机电致发光材料提供了全新的分子设计思路。本文纵观该领域的研究进展,对AIE化合物种类、发光机制及其相关应用做出了较为详尽的综述报道。具有AIE性质的化合物主要包括多芳基取代的杂环化合物、多芳基乙烯类化合物、分子内电荷转移化合物、含有氢键的化合物、聚合物等。这些化合物的AIE发光机制也各有不同,包括分子内旋转受限、非辐射失活衰减受限、分子构象扭曲以避免形成激基缔合物以及利用特殊的分子堆积方式如J-聚集、交叉分子堆积、由分子间的C—H…π作用或特殊的氢键作用形成相应的发光聚集体等。基于其特殊的AIE性能,AIE化合物可广泛应用于化学传感、生物传感、生物标记、电致发光以及逻辑门器件等领域。 相似文献
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含萘酰亚胺基的树枝状化合物具有特殊的发光性能和电学性质,其中一个重要特征是它还具有优异的光诱导电子转移性能,从而引起了人们的广泛关注.近年来科学家们已经合成了多种新型的含萘酰亚胺基树枝状化合物,它们在众多领域具有潜在的应用价值.综述了近年来含萘酰亚胺基的树枝状化合物的研究进展,介绍了部分树枝状萘酰亚胺基化合物的合成及其应用,这些化合物由于其独特的结构特点而具有特殊的性能,在化学传感器、光捕获天线材料、有机电致发光器件、药物传输、环境污染检测等领域具有重要的应用价值.最后,展望了此类化合物良好的应用前景. 相似文献
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有机电致发光器件具有直流电压驱动、主动发光、体积小、无视角限制、响应快,以及色彩全、制作工艺简单等优点,作为新型显示技术而倍受瞩目.在构建有机电致发光器件的三大材料中 (空穴传输材料、电子传输材料和发光材料),空穴传输材料的玻璃化温度(Tg)以及红色发光材料的色纯度和发光效率亟待改进.本论文通过对分子进行合适的裁剪与修饰,设计合成了具有良好应用前景的空穴传输材料和红色发光材料,研究了化合物的物化性质与分子结构的关系以及它们在器件上的应用. 相似文献
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对电致发光材料及器件(ELDs)发光性能的优化,一个重要的途径是在材料的组合中,要既具有空穴传输功能团,又具有电子注入功能团,并使两者的传输效率应尽量达到一个恰当的平衡,提高载流子传输中空穴与电子的复合几率,降低驱动电压,提高激子的发生几率,并对发光材料的发光区域进行控制[1].为此,在电致发光材料的分子设计及合成上,常需提供分子中含有空穴传输功能基团和分子中含有电子注入功能基团的有机分子,作为构筑电致发光器件的材料化合物,或将这两种功能团纳入到一个有机分子或高分子中. 相似文献
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有机电致发光技术在通信、信息、显示和照明等领域显现出巨大的商业应用前景, 十几年来一直是光电信息领域的研究热点之一。相对于无机电致发光材料,有机电致发光材料具有许多优点。芴作为一种具有刚性平面联苯结构的化合物,由于具有宽的能隙、高的发光效率和结构上易于修饰等特点,已成为一类受到各方关注的蓝光生色团。因此,芴类蓝光生色团在合成高效稳定电致蓝光材料、聚芴β相结构的调整、多功能化、主体材料、白光材料、有机激光及有机纳米发光材料等方面得到了广泛的应用。本文从材料合成的角度综述了芴类蓝光生色团在合成有机电致发光材料方面所取得的最新研究进展,讨论了芴类蓝光生色团在上述领域应用过程中所存在的问题和功能拓展方向,并对下一步需要研究的热点问题做了展望。 相似文献
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Different generations of carboxyl-terminated poly(aryl ether) dendrimers bearing a diphenylanthracene core were designed and synthesized. It is interesting to see that not only two-generation dendrimers but also one-generation dendrimers can be fabricated into thin films by self-deposition. Fluorescence spectra indicate that increasing the generation number of a dendrimer can effectively control the quenching of the fluorescence. Moreover, the fluorescence property of the diphenylanthracene core of the dendrimers in a solid film is quite similar to that of one in a solution, which is important for designing light-emitting materials. 相似文献
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Paola Ceroni Mauro Maestri Sang-kyu Lee Marius Gorka 《Journal of organometallic chemistry》2004,689(24):4375-4383
Suitably designed luminescent dendrimers can play a role of ligands for luminescent and non-luminescent metal ions. This combination leads to species capable of exhibiting interesting and unusual properties, including (i) shielding excited states from quenching processes, (ii) light harvesting, (iii) conversion of incident UV light into visible or infrared emission, and (iv) metal ions sensing with signal amplification. 相似文献
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Yihan Wang Ao Ying Shaolong Gong 《Journal of polymer science. Part A, Polymer chemistry》2024,62(2):241-265
During the past decade, the discovery of thermally activated delayed fluorescence (TADF) materials has significantly boosted the development of organic light-emitting diode (OLED) technology. Compared with small-molecule and polymeric TADF materials, TADF dendrimers have emerged as promising emitters for solution-processed OLEDs because they have the integrated advantages of TADF small molecules and polymers in achieving high efficiency, excellent solution processability, and precise molecular structures. In recent years, TADF dendrimers have experienced important advances in molecular design, mechanism exploration and device performance. Herein, we present a comprehensive review of solution-processable TADF dendrimers, mainly focusing on their molecular design principles and structure–property correlations. The advanced device performances of these dendrimers are also summarized. Finally, we proposed the prospects and challenges on the development of TADF dendrimers. 相似文献
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《结构化学》2016,(12)
A series of star-shaped molecules with benzene core and naphthalimides derivatives end groups have been designed to explore their optical,electronic,and charge transport properties as charge transport and/or luminescent materials for organic light-emitting diodes(OLEDs). The frontier molecular orbitals(FMOs) analysis has turned out that the vertical electronic transitions of absorption and emission are characterized as intramolecular charge transfer(ICT). The calculated results show that the optical and electronic properties of star-shaped molecules are affected by the substituent groups in N-position of 1,8-naphthalimide ring. Our results suggest that star-shaped molecules with n-butyl(1),benzene(2),thiophene(3),thiophene S?,S?-dioxide(4),benzo[c][1,2,5]thiadiazole(5),and 2,7a-dihydrobenzo[d]thiazole(6) fragments are expected to be promising candidates for luminescent and electron transport materials for OLEDs. This study should be helpful in further theoretical investigations on such kind of systems and also to the experimental study for charge transport and/or luminescent materials for OLEDs. 相似文献
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Garzoni M Cheval N Fahmi A Danani A Pavan GM 《Journal of the American Chemical Society》2012,134(7):3349-3357
The construction of hierarchical materials through controlled self-assembly of molecular building blocks (e.g., dendrimers) represents a unique opportunity to generate functional nanodevices in a convenient way. Transition-metal compounds are known to be able to interact with cationic dendrimers to generate diverse supramolecular structures, such as nanofibers, with interesting collective properties. In this work, molecular dynamics simulation (MD) demonstrates that acetate ions from dissociated Cd(CH(3)COO)(2) selectively generate cationic PPI-dendrimer functional fibers through hydrophobic modification of the dendrimer's surface. The hydrophobic aggregation of dendrimers is triggered by the asymmetric nature of the acetate anions (AcO(-)) rather than by the precise transition metal (Cd). The assembling directionality is also controlled by the concentration of AcO(-) ions in solution. Atomic force (AFM) and transmission electron microscopy (TEM) prove these results. This well-defined directional assembly of cationic dendrimers is absent for different cadmium derivatives (i.e., CdCl(2), CdSO(4)) with symmetric anions. Moreover, since the formation of these nanofibers is controlled exclusively by selected anions, fiber disassembly can be consequently triggered via simple ionic competition by NaCl salt. Ions are here reported as a simple and cost-effective tool to drive and control actively the assembly and the disassembly of such functional nanomaterials based on dendrimers. 相似文献
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Ribierre JC Ruseckas A Samuel ID Barcena HS Burn PL 《The Journal of chemical physics》2008,128(20):204703
A detailed study of the photophysics of a family of bisfluorene-cored dendrimers is reported. Polarized time-resolved fluorescence, singlet-singlet exciton annihilation and fluorescence quantum yield measurements were performed and used to understand how the dendron structure affects the light-emitting properties of the materials. The exciton diffusion rate is similar in all films studied. An increase in the nonradiative deactivation rate by nearly one order of magnitude is observed in films of dendrimers with stilbenyl and carbazolyl based dendrons as compared to solutions, whereas the dendrimers with biphenyl and diphenylethylenyl dendrons showed highly efficient emission (photoluminescence quantum yields of 90%) in both solution and the solid state. The results of the materials that show fluorescence quenching can be explained by the presence of quenching sites at a concentration of just a fraction of a percent of all macromolecules. A possible explanation of this quenching is hole transfer from the emissive chromophore to the dendron in a face-to-face geometry. These results are important for the design of efficient blue emitters for optoelectronic applications. 相似文献
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Considerable research is currently focused on the organic electrophosphorescent materials due to their high luminescent efficiency. Electrophosphorescent material based on heavy metal complexes is a hot topic in the research of organic light-emitting devices (OLEDs). We synthesized a series of novel cyclometalated heavy metal complexes by introducing pheny-quinoline moieties into ligands by means of a convenient method (Scheme 1), and investigated their photophysical properties which indicated that those compounds exhibited red light-emitting and high luminescent efficiency.These complexes have been characterized by 1H NMR, UV-vis and PL. 相似文献
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采用量子化学方法研究了给体-π桥-受体-π桥-给体(D-π-A-π-D)型萘基衍生物及其“CH”/N 杂原子取代衍生物的电子、光谱和电荷传输性质. 计算结果表明, 分子结构的变化引起了电子结构和能隙的变化, 进而改变了吸收和发射光谱. 其中, 衍生物的最大发射波长几乎覆盖了可见光区域(447.7-743.1 nm). 而且, 光谱的Stokes 位移较大(106.1-222.4 nm), 产生的原因在于, 与基态结构相比较, 衍生物的激发态结构中分子主干存在两个相连部分更为平面的构型. 计算结果还显示, 所有衍生物都可以作为有机电致发光二极管中的空穴传输材料. 相似文献
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《中国科学:化学(英文版)》2015,(6)
Organic light-emitting diodes(OLEDs) have been extensively studied since the first efficient device based on small molecular luminescent materials was reported by Tang. Organic electroluminescent material, one of the centerpieces of OLEDs, has been the focus of studies by many material scientists. To obtain high luminosity and to keep material costs low, a few remarkable design concepts have been developed. Aggregation-induced emission(AIE) materials were invented to overcome the common fluorescence-quenching problem, and cross-dipole stacking of fluorescent molecules was shown to be an effective method to get high solid-state luminescence. To exceed the limit of internal quantum efficiency of conventional fluorescent materials, phosphorescent materials were successfully applied in highly efficient electroluminescent devices. Most recently, delayed fluorescent materials via reverse-intersystem crossing(RISC) from triplet to singlet and the "hot exciton" materials based on hybridized local and charge-transfer(HLCT) states were developed to be a new generation of low-cost luminescent materials as efficient as phosphorescent materials. In terms of the device-fabrication process, solution-processible small molecular luminescent materials possess the advantages of high purity(vs. polymers) and low procession cost(vs. vacuum deposition), which are garnering them increasing attention. Herein, we review the progress of the development of small-molecule luminescent materials with different design concepts and features, and also briefly examine future development tendencies of luminescent materials. 相似文献