铱配合物在磷光化学传感器中的应用

由于在生物领域和物联网领域的广泛应用,化学传感器在近期发展迅速.相比于纯有机分子的荧光化学传感器,基于重金属配合物的磷光化学传感器由于发光寿命长,斯托克斯位移大等优点越来越引起人们的广泛关注.重金属铱配合物三线态寿命短,发光效率高而且配合物的发射波长容易受配体的改变而发生变化,因此成为最好的磷光传感器材料之一.本文介绍了铱配合物在磷光化学传感器领域中的应用,具体包括:阳离子传感器、阴离子传感器、氧分子传感器、氨基酸传感器、pH传感器等,并指出了相比于其它磷光化学传感器,基于铱配合物的磷光化学传感器的优势以及目前所存在的问题,最后,对基于铱配合物的磷光化学传感器的研究和发展方向进行了展望.     

小分子铱配合物及其电致发光

由于磷光金属配合物可以同时利用单线态和三线态激子发光,使有机电致发光器件的理论内量子效率达到100%,突破了25%的极限。因而以磷光金属配合物为发光材料制成的器件备受关注。在这些金属配合物中,铱配合物由于具有较强的发光特性、发光波长可调性、较好的热稳定性和电化学稳定性以及能够形成便于蒸镀的中性分子,而成为最有应用潜力的电致磷光材料。本文综述了近几年铱配合物磷光材料在分子设计与合成方法、发光机理及器件构筑等方面的研究进展。特别介绍与讨论了磷光铱配合物的两种发光机理,即基于同配体铱配合物或异配体铱配合物的主配体到中心金属离子的电荷转移三线态(³MLCT)发射和基于异配体铱配合物的辅助配体三线态(³LC)发射。根据反应条件的差异,归纳总结了合成铱配合物常用的4种方法以及合成fac式和mer式的铱配合物的方法。还根据材料的发光颜色及其电致发光的不同,对磷光铱配合物材料进行了分类与讨论。此外,简要介绍了用于器件制作的主体材料。最后,展望了金属有机配合物电致磷光材料的发展前景,并提出了今后磷光材料的发展方向。     

红色铱配合物磷光材料及器件的研究进展

有机电致发光器件具有驱动电压低、高亮度、高效率等优点,引起了研究人员的广泛关注,在固态照明和平板显示领域具有广阔应用前景。 在绿、蓝、红三基色器件中,绿光器件和蓝光器件的性能普遍优于红光器件,基本满足了产业化的需要;目前红色有机电致发光材料及器件的研究进展相对缓慢。 因为红光材料的能隙较窄,致使主客体材料之间能级匹配困难,导致红光器件普遍效率低、色纯度差,但是,红光材料是获得白光器件必不可少的材料。 因此,如何获得高性能红光材料对于有机电致发光器件的发展至关重要。 本文综述了近年来红色铱配合物磷光材料及器件的研究进展,对提升效率和色纯度的方法进行重点阐述;并结合现有工作,对红色有机电致磷光材料与器件的前景进行展望。     

含铱配合物聚合物磷光材料及其电致发光性能

聚合物电致发光器件由于在大面积平板显示和固态照明上的潜在应用,在学术研究和工业应用领域引起了广泛的关注.聚合物电致发光器件可以通过溶液加工的方法制备,制作工艺简单,成本低、材料省,并且可以实现大面积柔性显示.和荧光聚合物材料相比,磷光铱配合物聚合物材料可以同时利用单线态和三线态激子发光,器件的内量子效率理论上能达到100%,突破了传统25%的极限,因而受到广泛关注.基于此,本文综述了含铱配合物聚合物磷光材料的研究进展,主要对含铱配合物线型聚合物和超分子聚合物的合成、结构特点以及光电特性进行了总结,并讨论了聚合物结构对材料性能的影响.     

基于离子型铱配合物的发光电化学池

基于离子型过渡金属配合物的发光电化学池在信息显示和固体照明方面极具应用前景,因此其相关材料的设计、开发和器件性能的提高等工作在近几年引起了人们广泛的研究兴趣。在各类离子型过渡金属配合物中,离子型铱配合物由于发光效率高,发光颜色容易调节等优点而受到广泛关注。本文综述了近几年来离子型铱配合物在发光电化学池中的应用进展,重点评述了不同发光颜色的发光电化学池的制备和器件的高性能化等方面的研究进展,并展望了基于离子型铱配合物的发光电化学池这一研究领域的发展前景。     

有机电致发光红色发光材料研究进展

本文总结了近年来有机金属配合物、分子内电荷转移化合物、稠环芳香类化合物以及齐聚物等几类有机电致发光红色发光材料的研究进展,详细介绍了它们在有机电致发光器件中的应用,并对有机电致发光红色发光材料未来的研究方向作了展望.     

系列2-苯基喹啉类铱配合物的合成及电化学发光性能研究

以4-甲氧羰基-2-苯基喹啉为环金属配体,N^N辅助配体为解离配体合成了一系列离子型环金属铱配合物.配合物的结构通过质谱、核磁进行了表征.配合物1还测试了其单晶结构.对配合物的紫外、磷光性质进行了表征,溶液状态下为红光发射,波长在610～620 nm之间,磷光寿命在133～496 ns之间,量子效率在0.7%～16.6%之间.铱配合物的电化学发光与23Ru(bpy)+有所不同,发光电位比23Ru(bpy)+要高,且大部分铱配合物在正负电位都能发光,最大发光强度是23Ru(bpy)+的三倍.     

基于四齿配体的蓝光d8金属配合物及其OLED应用的研究进展

用于有机发光二极管(OLED)的红光和绿光磷光金属配合物材料在稳定性和发光效率方面均已达到了目前产业化应用的要求,而蓝光磷光配合物则在稳定性方面无法达到应用条件。高能量的激发态以及d-d态引起的配合物分解是造成蓝光磷光OLED器件稳定性差的原因之一。采用四齿配体开发d~8金属配合物是同时提升配合物发光效率和稳定性的途径之一,有望在蓝光磷光材料和器件应用方面取得突破。本文总结了基于四齿配体的蓝光铂(Ⅱ)和钯(Ⅱ)配合物的研究进展,通过探讨配体结构对配合物光物理性质和稳定性的影响,为继续开发具有应用前景的蓝光金属配合物材料提供了指导性方向。     

聚合物磷光材料的研究进展北大核心CSCD

金属配合物磷光材料因为其能同时利用单线态激子和三线态激子,引起了人们广泛关注。聚合物磷光材料(polymer phosphorescent materials,PPMs)同时具备小分子金属配合物的良好发光特性和高分子的优异物理性能,如容易挠曲、可溶液加工和良好的成膜性。本文综述了近年来聚合物磷光材料的研究进展,总结了聚合物磷光材料的合成方法及其在有机电致发光器件(OLED)方面的应用。最后从电磷光发光聚合物的分子结构设计出发,在电磷光发光聚合物领域业已取得进展的基础上,分析了电磷光发光聚合物在电致发光领域应用中存在的一些问题,并展望了电磷光聚合物今后的发展方向。     

聚合物磷光材料的研究进展

金属配合物磷光材料因为其能同时利用单线态激子和三线态激子,引起了人们广泛关注。聚合物磷光材料(polymer phosphorescent materials,PPMs)同时具备小分子金属配合物的良好发光特性和高分子的优异物理性能,如容易挠曲、可溶液加工和良好的成膜性。本文综述了近年来聚合物磷光材料的研究进展,总结了聚合物磷光材料的合成方法及其在有机电致发光器件(OLED)方面的应用。最后从电磷光发光聚合物的分子结构设计出发,在电磷光发光聚合物领域业已取得进展的基础上,分析了电磷光发光聚合物在电致发光领域应用中存在的一些问题,并展望了电磷光聚合物今后的发展方向。     

High‐Performance Organic Electroluminescence: Design from Organic Light‐Emitting Materials to Devices

Organic electroluminescence is considered as the most competitive alternative for the future solid‐state displays and lighting techniques owing to many advantages such as self‐luminescence, high efficiency, high contrast, high color rendering index, ultra‐thin thickness, transparency, flat and flexibility, etc. The development of high‐performance organic electroluminescence has become the continuing focus of research. In this personal account, a brief overview of representative achievements in our study on the design of highly efficient novel organic light‐emitting materials (including fluorescent materials, phosphorescent iridium(III) complexes and conjugated polymers bearing phosphorescent iridium(III) complex) and high‐performance device structures together with working principles are given. At last, we will give some perspectives on this fascinating field, and also try to provide some potential directions of research on the basis of the current stage of organic electroluminescence.     

Functionalized polynorbornenes with fragments of cholic acid and luminophore complexes of iridium(III) and copper(I) in side chains. Synthesis and photophysical properties

Copolymers containing fragments of cholic acid and luminophore complexes of iridium(III) and copper(I) in the side chains have been synthesized by metathesis polymerization. Photophysical properties of the obtained compounds have been investigated. Iridium-containing copolymers demonstrate intense photoluminescence of green, bluish-green and red colors. Copper-containing copolymers generate radiation of green and yellow-green colors. The color of photoluminescence of the metal-containing polymers is determined by the nature of copper(I) and iridium(III) complexes bonded to polymer chain.     

Simple Conjugated Polymers with On‐Chain Phosphorescent Iridium(III) Complexes: Toward Ratiometric Chemodosimeters for Detecting Trace Amounts of Mercury(II)

For the development of excellent optical probes for mercury(II), a series of simple conjugated polymers that contain phosphorescent iridium(III) complexes as receptors for mercury(II) were designed and synthesized. These conjugated polymers showed energy transfer from the polymer host to iridium(III) complex guest in both solution and the solid state. Unexpectedly, they can work as excellent polymer chemodosimeters for mercury(II) by utilizing the mercury(II)‐induced decomposition of iridium(III) complex. They exhibit a pronounced optical signal change with switchable phosphorescence and fluorescence, even when the concentration of a solution of mercury(II) in THF was as low as 0.5 ppb. With the addition of mercury(II), the phosphorescent emission intensity of iridium(III) complexes was quenched completely. As the emission from polymer backbones increased, the emission wavelength was redshifted simultaneously, thereby realizing ratiometric detection. Excellent selectivity toward mercury(II) over other potentially interfering cations was also realized. In addition, an obvious emission color change of polymer solution from red to yellow‐green was observed, thus realizing a “naked‐eye” detection of mercury(II). More importantly, the solid films of these polymer chemodosimeters also exhibited high sensitivity and rapid response to mercury(II), thereby demonstrating the possibility of the fabrication of sensing devices with fast and convenient detection of mercury(II). The sensing mechanism was also investigated in detail. This is the first report on chemodosimeters based on conjugated polymers with phosphorescent iridium(III) complexes.     

Multifunctional red phosphorescent bis-cyclometallated iridium complexes based on 2-phenyl-1,2,3-benzotriazole ligand and carbazolyl moieties

Multifunctional phosphorescent bis-cyclometallated iridium(III) complexes based on the 2-phenyl-1,2,3-benzotriazole moiety and bearing branched hole-transporting carbazole fragments were synthesized. The isolated compounds were found to be amorphous and expressed very good solubility. Introduction of flexible aliphatic chains of various lengths into the iridium complexes enabled manipulation of their glass transition temperature. The iridium complexes exhibited red phosphorescence emission at 650 nm with the lifetime of 5.7 μs and phosphorescence quantum yields of 0.22 and 0.17 in solution and solid state, respectively, at room temperature. The shielding effect of the carbazolyl moieties on the concentration quenching of phosphorescence of the iridium centers was found to result in the increased excited state lifetime and quantum yield due to the suppressed exciton migration. Non-optimized OLED devices, based on the phosphorescent bis-cyclometallated iridium(III) complex without host material were fabricated and their electroluminescence properties were evaluated.     

Cationic iridium(III) complexes for phosphorescence staining in the cytoplasm of living cells

Two cationic iridium(III) complexes with bright green and red emissions were demonstrated as phosphorescent dyes for living cell imaging. In particular, their exclusive staining in cytoplasm, low cytotoxicity and reduced photobleaching, as well as cell membrane permeability, make the two complexes promising candidates for the design of specific bioimaging agents.     

Evolution of 2, 3′-bipyridine class of cyclometalating ligands as efficient phosphorescent iridium(III) emitters for applications in organic light emitting diodes

Nowadays, the design and development of novel phosphorescent iridium(III) complexes for various optoelectronic applications is a well-recognized area of research. The fascinating photophysical properties of iridium(III) compounds are strongly influenced by the spin-orbit coupling exerted by the iridium(III) core, usually resulting in intense emissions with short excited-state lifetimes, which can be precisely controlled with the aid of molecular engineering of the chelating ligand. This review focuses on the recent developments and state of the art knowledge on phosphorescent iridium(III) compounds, especially on heteroleptic complexes derived from 2,3′-bipyridine class of cyclometalating and ancillary ligands, highlighting the excited state phenomenon behind their emission behavior.     

位阻型有机电致磷光材料的研究进展

重金属旋轨耦合作用使磷光有机发光二极管的内量子效率在理论上可达100%,突破了传统有机荧光二极管内量子效率为25%的限制,是目前最有潜力的第三代显示器.但是,磷光材料常因浓度猝灭、三线态湮灭、二聚体发光等因素影响器件性能.位阻型磷光材料能够抑制分子间的强相互作用,从而解决了上述问题.本文作者综述了近年来具有大体积空间位阻效应的铱(III)、铂(II)、锇(II)等有机小分子磷光材料的研究进展,讨论了其目前存在的问题和未来的发展趋势.     

Thermal‐Responsive Phosphorescent Nanoamplifiers Assembled from Two Metallophosphors

Thermal‐responsive phosphorescent nanotubes have been fabricated from the co‐assembly of two neutral iridium complexes, which behave as the antenna chromophores and energy acceptors, respectively, in these highly ordered crystalline superstructures. By tuning the acceptor doping ratio in a range of 0 to 0.5 %, these tubes display color‐tunable phosphorescence from green to red at room temperature, and it is attributed to the highly efficient light‐harvesting and energy transfer within these materials. For the same reason, the acceptor emission in the nanotubes is amplified more than 800 times with respect to its pure non‐emissive solid sample. The doped tubes show reversible thermal‐responsiveness, in which the energy transfer was completely suppressed at 77 K and reactivated at room temperature. These processes were characterized by the in situ emission color (green, orange, and red) and spectral changes and lifetime measurements of isolated nanotubes. The temperature‐controlled exciton dynamics are responsible for the luminescent thermochromism in these crystalline materials.