稀土铽配合物的有机发光二极管

有机小分子和有机高分子的发光二极管在可见光区内有非常高的量子效率，因而受到人们的高度重视．采用二胶（TPD），8羟基喹啉铝（Alq3）等有机小分子作为空穴和电子输运层所作的发光二极管[1]的量子效率可达10％，采用聚对苯乙炔（PPV）高分子聚合物作空穴输运层，有机小分子2     

一类新型高荧光性类水滑石（Al-HTLc）的合成与性能

采用共沉淀法,合成、组装得到一类将铝离子（Al^3＋）量减少到一定值的镁铝型类水滑石,并使分散于其镁铝水滑石板层上的铝离子与板层间溶于亲油性阴离子中的计量8-羟基喹啉（8-HQ）配位,获得一类新型高荧光性类水滑石（Al-HTLc）．采用荧光光谱、红外光谱、紫外光谱、XRD、XPS和热分析等对其进行了表征．研究结果表明,该Al-HTLc在紫外光下可发出荧光强度高达4．9×10^5（a．u.）的强烈蓝绿色荧光（487nm）,荧光寿命为21．24ns,光量子产率为67％,高于纯8-羟基喹啉铝（Alq3）,且具有更高热稳定性,有望作为一类高性能的新型荧光材料而获得应用．     

含苝酰亚胺和8-羟基喹啉双官能团的金属络合物型发光材料

应用Gabriel反应替代传统的亚酰胺缩合法．成功地合成了一种含苝酰亚胺发色团的金属络合物型发红光材料(Pery-q)3Al。在其结构中引入电子传输功能单元8-羟基喹啉铝(Alq3)。在(Pery-q)3Al体系中,由于单线态之间的能量转移。导致Alq3单元的荧光发生了严重的淬灭。     

树枝状有机电致发光材料*

高度有序、三维结构的树枝状大分子(Dendrimers)作为功能有机材料越来越引起人们的兴趣。与传统的小分子和高分子发光材料相比,树枝状化合物在发光材料方面的应用具有无可比拟的优势。树枝状发光材料的发光特性可以方便地由中心核的调换不同的荧光染料来实现,另外大量的表面功能团和不同的代数可供选择来得到一些有趣的性质,如载流子传输功能、区域隔离效应、溶解性和天线效应等。该类型的发光材料已被认为是第三类电致发光材料。本文简要介绍近期树枝状分子在有机电致发光材料领域中的研究进展,评述树枝状分子在该研究领域所特有的优势,重点介绍了树枝状化合物的设计及其对应的性质,并进一步展望树枝状分子未来在有机电致发光领域的研究前景。     

化学键分解解析法在电致发光材料Alq3中的应用

利用B3LYP／6—31 G(d)和CIS／6-31G(d)方法分别优化了有机小分子电致发光材料径式8-羟基喹啉铝(Alq3)的基态与第一激发态结构。化学键分解解析法计算结果表明,A配体与Alq2片段间的静电作用能分别高于另外两个配体与Alq2之间的相互作用。因此,Alq3的HOMO轨道定域于A配体上,A配体在激发态时由于较低的静电吸引作用易于发生结构的弛豫。     

含有Alq3和Znq2的可交联聚合物的合成与表征

合成了溶解性优良、带有可聚合链段的8．羟基喹啉金属螫合物(Alq3和Znq2)单体,在室温下通过紫外光照射,形成热力学性能稳定、8．羟基喹啉金属螫合物含量高(50(wt)％以上)的交联聚合物。这种材料可以解决使用旋涂的方法制备器件带来的底层溶解的问题,从而实现大面积、多层电致发光器件的制备,还可以通过光刻手段实现器件涂层图案化,是器件实现全彩色、超像素方法之一。其光致发光和电致发光性质证明这种材料本身以及其加工性能在有机,高分子平面显示技术领域有一定应用价值。     

固定HCG抗体膜的跨膜电位

高分子膜作为一项新兴技术,在很多领域得到日益广泛的应用.近十几年,随着生物工程和生物传感器的迅速发展,高分子生物功能膜的研究倍受重视.高分子生物功能膜是采用固定化技术,将具有分子识别功能的材料(如酶、抗原、抗体等)固定在高分子膜上而制得的.在固定化膜表面发生的生物化学反应,可以引起膜的荷电状态的变化,从而导致跨膜电位的变化。有关固定化膜的报导较多,但主要限于固定化的方法及其应用方面的研究,而有关高分     

生物电化学传感器中煌聚合物材料

对聚合物材料在生物电化学传顺中的应用进行了评述,包括高分子媒介体化合物、高分子阻挡膜、酶固定化材料和电解聚合物材料。并指出今后提高生物电化学传感器性能、改善和改变其表面特性,也依赖于聚合物材料的应用。     

高分子化8-羟基喹啉锂的合成与静电自组装研究

设计合成了甲基丙烯酸二甲氨基乙酯(DM)含量为9.69%的丙烯酸甲酯共聚物(CPA),将制得的5-氯甲基-8-羟基喹啉(CHQ)挂接到CPA上,得到季铵型高分子化8-羟基喹啉(CPA-HQ)后,与金属离子Li+配位得到CPA-HQ-Li.化合物结构通过红外、紫外和荧光光谱等表征.多层超薄膜用CPA-HQ-Li和聚阴离子电解质(全氟磺酸)通过静电自组装制得.自组装膜的紫外和荧光相对于溶液(溶剂为四氢呋喃)发生了红移,膜的紫外吸收强度随组装膜层数增加线性增大,荧光强度随膜层数增加线性递减.高分子化8-羟基喹啉锂溶液和自组装膜的紫外和荧光光谱与文献报道一致.实验结果表明这种材料可用于有机电致发光器件(OLEDs)的制备.     

手性荧光传感器的研究进展

随着手性化合物在制药、不对称合成、生物科学及临床医学等领域应用的增长,迫切需要发展一种快速、灵敏的对映异构体检测技术。手性荧光传感器引起了人们的高度关注。近年来,发展了很多手性荧光传感器并对手性化合物表现出较高的选择性和灵敏度。该文综述了以1,1'-联-2-萘酚衍生物、杯芳烃衍生物、高分子聚合物、纳米材料、金属有机多孔材料为骨架的手性荧光传感器,总结了其在手性化合物识别中的应用,并展望了手性荧光传感器的发展方向。     

8-羟基喹啉铝高分子薄膜的荧光特性

In this paper, the solid state. polymer thin films of 8-hydroxylquinoline aluminum (Alq3) were made by spinning coat method. The fluorescence efficiencies and the luminescence spectra of them were measured via the laser systems. Various experimental factors were considered and tested. It was found that the peak wavelength of the luminescence spectra of the Alq3 polymer films shifted and that the purity of the samples affected its fluorescence efficiencies: the fluorescence efficiencies of impure samples were about three-fourth of that of the purified ones; fluorescence efficiencies of Alq3 doped in PMMA polymer was higher than that doped in PC and PEO. Under certain conditions, transparent thin film 10 layers can be achieved. This kind of polymer thin film of Alq3 exhibits well fluorescence response, but also has good stability. Spin coat method can greatly reduce the technical requirements comparing with the vacuum plating method.     

Multi-beam single-molecule defocused fluorescence imaging reveals local anisotropic nature of polymer thin films

We developed a method to determine full three-dimensional orientation distribution of individual molecules based on wide-field defocused fluorescence imaging. Excitation efficiencies of out-of-plane oriented molecules were improved dramatically by illuminating molecules with multiple laser beams. Our high throughput approach allowed us to obtain unbiased statistical distributions of orientations of doped molecules in spin-coated polymer thin films. We found thickness- and glass transition temperature-dependent distributions of the molecular orientations which reflect local chain orientations and relaxation in the polymer thin films.     

掺铽聚丙烯薄膜的研究

合成了化学组成为Ｙ１－ｘＴｂｘＬ３和Ｌａ１－ｘＴｂｘＬ３（Ｌ＝Ｃ８Ｈ７Ｏ２）的两种荧光粉，将其掺杂到聚丙烯中，制得两种聚丙烯荧光薄膜，通过测试机械性能，微分扫描式量热法分析，紫外分光光谱和荧光光谱测定，研究膜的物理和荧光性能。结果表明：这两种掺铽聚丙烯膜在３６５或２５４ｎｍ紫外光激发下，都能发出黄绿色荧光。掺入Ｙ１－ｘＴｂｘＬ３的聚丙烯膜的荧光强度大于掺Ｌａ１－ｘＴｂｘＬ３的聚丙烯膜。     

Thermal change of organic light-emitting ALQ3 thin films

A series of Alq3 thin films with the thicknesses of 50, 100, and 200 nm was deposited on Si substrates at room temperature using the thermal evaporation method. The thermal crystallization process of Alq3 thin films, especially 50 nm thick films, was successfully examined using high-temperature X-ray diffraction (HT-XRD) with the in-plane scan mode. Film thickness, density, and changes in surface roughness while heating were determined using X-ray reflectometry (XRR). The decreased density and increased surface roughness, which were accompanied by sublimation, indicate the instability of the Alq3 film. Thus, thermal instability is a major factor for device failure.     

Supramolecular structures and assembly and luminescent properties of quinacridone derivatives

The synthesis and single-crystal X-ray structures of two quinacridone derivatives, N,N'-di(n-butyl)quinacridone (1) and N,N'-di(n-butyl)-1,3,8,10-tetramethylquinacridone (2), are reported, and the 1H NMR, absorption, photoluminescent (PL), and electroluminescent (EL) characteristics are presented. Both these crystal structures are characterized by intermolecular pi...pi and hydrogen bonding interactions. The intermolecular pi...pi interactions lead to the formation of molecular columns in the solids of 1 and 2, and the interplanar contact distances between two adjacent molecules are 3.48 and 3.55 angstroms, respectively. Crystals of 1 display shorter intermolecular pi...pi contacts and higher density than 2. These results suggest that tighter intermolecular interactions exist in 1. The 1H NMR, absorption, and PL spectra of 1 and 2 in solutions exhibit concentration-dependent properties. The PL quantum yields of 1 in solutions decrease more quickly with the increase of concentration compared to that of 2 in solutions. For solid thin films of Alq3:1 (Alq3 = tris(8-hydroxyquinolinato)aluminum), emission intensities dramatically decrease and obvious red shifts are observed when the dopant concentration is above 4.2%, while for films of Alq3:2, a similar phenomenon occurs when the concentration is above 6.7%. EL devices with Alq3:1 as emitting layer only show high efficiencies (20.3-14.5 cd/A) within the narrow dopant concentration range of 0.5-1.0%. In contrast, high efficiencies (21.5-12.0 cd/A) are achieved for a wider dopant concentration range of 0.5-5.0% when Alq3:2 films are employed as emitting layer. The different PL and EL concentration-dependent properties of the solid thin films Alq3:1 and Alq3:2 are attributed to their different molecular packing characteristics in the solid state.     

Chromophoric thin film based on cellulose triacetate blends for sensing metal ions

Chromophoric sensors were made based on 8-hydroxyquinoline immobilized onto a thin film of a polymer blend matrix. The thin films were made by the solution casting method using cellulose triacetate and polyethylene glycol (PEG 600) as plasticizer and pore-forming agent. Different contents of PEG 600 additive were investigated. The prepared films were characterized by FTIR and thermal analysis. The absorption and fluorescence spectra of different films were dependent on the content of PEG 600 with clear quenching of the fluorescence of the film that contains PEG 600 compared to that with zero content. This behavior was attributed to the collective effect of hydrogen bonding (intra- and intermolecular hydrogen bonding) that enhances the process of excited-state proton transfer. This result is favorable to a responsive sensor that shows fluorescence off in the absence of metal ions and fluorescence on upon metal ion chelation. The detection of 5 × 10⁻⁵ M of Al³⁺, Zn²⁺ and thallium (I) in aqueous solution has been observed with the fluorescence method. The result obtained is consistent with the enhancing effect of PEG 600 in the detectability of metal ions. Compared with the detection of Al³⁺ and Zn²⁺, the sensor shows better detection of thallium (I), with clear fluorescence spectra.     

Fluorescence characteristics and photostability of benzoxazole derived donor-acceptor dyes in constrained media

The spectroscopic properties and photoreactivity of 2-(4-dimethylaminostryl)benzoxazole and its butadienyl analogue (abbreviated as DMASBO and BODB, respectively) were investigated in thin films of PS, PMMA and PVA polymer matrices as well as immobilized on silica surface. The experimental results showed that the investigated benzoxazole derivatives are sensitive to the polarity of its microenvironment even in the glassy matrices and in the solid state. The micropolarity of PVA and silica surface is greater than that of PMMA and PS. The combined results of fluorescence quantum yield and photoisomerization indicated that the size of the free volume within the polymer matrix influence strongly the photochemical reactivity of the used dyes. In PVA, which offers the smaller free volume, the photoreaction is totally blocked while the fluorescence yield is extremely enhanced relative to those in solutions and other polymer matrices. This is associated with an emission of green laser from DMASBO-PVA doped film when pumped by nitrogen laser (337 nm). The results showed that the present dyes are excellent probes for non-fluorescent systems presenting constrained geometry. The spectra of amorphous solid thin films of both dyes were also measured and show large red shifts relative to those in solutions indicating symmetric aggregation of molecules in the solid crystals.     

Fabrication of polymer Langmuir-Blodgett films containing regioregular poly(3-hexylthiophene) for application to field-effect transistor

Semiconducting thin films consisting of regioregular poly(3-hexylthiophene) (RR-PHT) and poly(N-dodecylacrylamide) (pDDA) were constructed by the Langmuir-Blodgett (LB) technique. A mixture of RR-PHT and pDDA spread from a chloroform solution on a water surface forms a stable monolayer, which can be transferred onto solid substrates by the LB method, yielding a well-defined polymer LB film. Surface morphology studies of the LB film indicate that the RR-PHT is dispersed uniformly throughout the surface. The polymer thin film was chemically doped by contacting with FeCl3 acetonitrile solution, and a conductivity of 5.6 S/cm was achieved. Further, the LB film was utilized as the semiconducting film in the field-effect transistor (FET), and mobilities of 2.2 x 10(-4) and 4.4 x 10(-4) cm2 V(-1) s(-1) were obtained by analyzing the saturated and linear regions of the current-voltage characteristic, respectively.     

Polyaniline thin film optical waveguides for integrated optics and VLSI prepared by vacuum evaporation technique

Polyaniline is emerging as an important polymer material which offers challenging opportunities for both fundamental research and new technological applications in waveguides. Metal doped polyaniline has been prepared initially in the form of powder by a solution growth technique. The emeraldine salt with doped metal was also prepared by solution growth technique. This powder was used for vacuum evaporation on optically flat glass substrate. The dark green doped (Fe, Al) polyaniline thin films were prepared by vacuum evaporation technique (10^?4 torr). Deposited waveguide thin films have been characterized structurally, using X‐ray diffraction (XRD), optically etc. Effective refractive index of the thin film waveguide was also calculated theoretically and experimentally. Waveguide parameters, namely refractive index, propagation loss and depth of vacuum deposited polyaniline thin films optical waveguide have been determined. The optical spectra and structure and waveguide parameters of vacuum deposited polyaniline thin films are strongly affected by the type of doping. It is possible to reduce the losses by addition of Fe to the vacuum deposited polyanine thin film and modify the effective refractive index (O_eff) according to particular requirements. Results are compared with the results in the literature. Copyright © 2002 John Wiley & Sons, Ltd.     

Optical Spectra of Polygermane/Mesoporous Silica Nanocomposites

Summary: The monitoring of poly(di-n-hexylgermane) (PDHG) optical spectra in a variety of structures ranging from a bulk film to a nanosize polymer confined into a nanopore of SBA-15 was performed using the fluorescence and fluorescence excitation spectra in the temperature range from 5 to 240 K as well as the absorption and FTIR spectra at room temperature. The observed data were compared with those obtained for poly(di-n-hexylsilane). It was shown that PDHG film absorption and fluorescence spectra strongly depend on the polymer thickness and consist of a number of bands which were assigned to centers with different amount of trans- and gauche- conformers of the polymer chains. Conformations of the polymer chains found in a thin film and in a 10 nm pore are similar while differing from the conformations of a thick film. Optical spectra of the confined PDHG are blue-shifted relative to those of a thin film. The PDHG polymer chain conformation becomes disordered with the decrease of the polymer film thickness and the nanopore size from 10 to 6 nm.