稀土有机配合物电致发光研究进展

稀土配合物发射带窄, 发射光谱具有类原子光谱性质, 色纯度高(半宽峰<10 nm), 非常适合于全彩色显示. 另外, 稀土配合物发光效率高, 理论上内量子效率可达100%. 因此, 稀土配合物是全色平板显示器件中理想的发光材料之一, 研究稀土配合物电致发光性质具有重要的实际意义和理论意义. 以稀土镧系离子配合物作为发光中心的电致发光器件的研究主要集中于发光效率比较高的Eu3+, Tb3+ 以及近红外的Nd3+, Yb3+和Er3+ 离子. 分类综述了近年稀土配合物电致发光研究的成果及其进展. 总结了不同类型的铕配合物、铽配合物的电致发光特性, 证明配体对于稀土离子的敏化作用非常重要; 总结了近红外的镱、钕、铒配合物在光放大、激光技术、生物医学等方面的潜在应用价值.     

近红外稀土荧光在功能材料领域的研究进展

稀土近红外荧光材料具有特征发射峰尖锐、光稳定性好和毒性低等特点。近年来,稀土近红外荧光材料在光纤通讯、激光系统、生物分析传感器及生物成像等方面的应用价值日渐突显,引起了研究者们的极大关注。特别是稀土近红外荧光材料已发展成一种新兴的荧光标记材料,并有希望替代有机染料和量子点应用于生物分析和医学成像。基于稀土近红外发光的荧光探针具有低自荧光背景、宽斯托克斯位移、强抑制光漂白、深层穿透组织和短暂分辨的优势,有潜力成为高灵敏度、高选择性的检测手段。利用稀土离子制备的各种荧光材料,如上转换纳米晶、介孔材料、脂基胶体、离子液体、离子胶体、金属有机框架等,由于荧光敏化机理不同,其近红外荧光性能也各有千秋。然而,稀土近红外荧光的真正挑战仍是提高近红外发光的量子效率。本文结合近红外荧光领域的最新进展,综述了不同的稀土近红外荧光设计思路,介绍了各种近红外稀土荧光功能材料,阐述了稀土离子在近红外荧光功能材料中的优势,并展望了稀土近红外荧光材料的发展前景。     

Tb3+/Eu3+镧系金属有机框架材料在荧光检测的研究进展

镧系金属有机骨框架（Lanthanide metal organic frameworks,Ln-MOFs）是以镧系离子为中心,与配体有机物组合的多孔材料,具有良好的光学性质,在许多领域有广泛的应用。不同的镧系离子与相应的有机配体结合,可组成不同性能的Ln-MOFs。在众多镧系元素中,Tb3+和Eu3+是良好的发光中心,常被用于组建发光Ln-MOFs。由Tb3+/Eu3+与有机配体形成的Ln-MOFs具有独特的荧光特性、较大stokes位移以及长发光寿命等优点在荧光检测领域具有重要应用。本文综述了基于Tb3+/Eu3+的Ln-MOFs在离子检测、生物标志物检测以及小分子检测领域的研究进展,对Ln-MOFs的发展前景进行了展望。     

近红外发光稀土配合物及杂化材料研究进展

稀土因其特殊的物理和化学性质,在信息技术、能源技术、生物技术等高科技领域及国防建设等方面都起着非常重要的作用,中国作为稀土大国,十分重视对稀土材料的研究和开发。稀土离子近红外发光(750～1700 nm)在激光和光纤通讯、医学诊断、免疫分析等热门领域的潜在应用,受到了科研人员的极大关注。稀土离子本身发光极弱,通过分子内传能有机配体可以敏化稀土离子发光,但稀土配合物常受外界干扰,其稳定性较差,若将其与凝胶、介孔材料、离子液体等无机基质复合,得到具有良好光、热稳定性和化学稳定性的有机/无机杂化材料。总结了近些年来近红外发光稀土配合物及近红外发光稀土杂化材料的研究进展,并对其发展前景进行了展望。     

稀土/L型沸石主-客体发光功能材料的研究进展

沸石微孔晶体材料作为客体功能物种的主体材料在主-客体组装化学中发挥着越来越重要的作用,在微型激光器、非线性光学、生物成像、光放大及光显示等高技术领域已显示出广阔、诱人的发展前景.本文介绍国内外,特别是河北工业大学在稀土/L型沸石主-客体杂化功能材料的组装、结构及其发光性能的研究工作,具体包括：稀土有机配合物在L沸石孔道内的组装、L型沸石-有机高分子透明杂化发光材料的制备及稀土有机配合物诱导控制的L型沸石自组装等.此外,本文对稀土/L型沸石主-客体杂化发光功能材料的研究进行了展望.     

Thermotropic lanthanidomesogens

Due to their high and variable coordination numbers leading to poorly predictable three-dimensional coordination spheres, the trivalent lanthanide metal ions are challenging molecular objects for introduction into thermotropic liquid crystals. Conversely, their predictive electronic, optical and magnetic metal-centred properties make them particularly attractive for being incorporated into switchable macroscopic materials responding to external electric and magnetic stimuli. We briefly describe here some of the important concepts and strategies leading to the recent successful preparation of luminescent thermotropic lanthanide-containing mesophases, for which the generic term lanthanidomesogens is proposed.     

微孔镧系配位聚合物

微孔配位聚合物与通常的微孔无机材料相比, 具有非常明显的优势. 而镧系离子特殊的光学和磁学性质, 更使得微孔镧系配位聚合物的研究成为热点. 本文简要地报道了微孔镧系配位聚合物的研究现状, 对一些微孔镧系配位聚合物的结构特点进行了描述, 讨论了影响微孔配位聚合物形成的主要因素. 一般来说, 线型配体往往能很好地将金属离子连接起来, 得到理想的微孔镧系配位聚合物; 选择合适的第二配体, 有利于构筑结构新颖的微孔镧系配位聚合物; 镧系收缩对能否形成微孔配位聚合物的影响并不明显, 只是轻稀土离子往往倾向于多结合一些小分子配体来满足更高的配位数.     

稀土无机发光材料:电子结构、光学性能和生物应用

目前,稀土无机发光材料在激光、光通讯、平板显示、荧光生物标记和纳米光电子器件等领域具有广泛的应用前景.稀土离子(从Ce到Yb)是一类性能优异的结构和光谱探针,其在不同介质材料中的光学性能主要取决于其局域态的电子结构和激发态动力学.对稀土发光材料开展深入的光学和光电子学基础研究有助于发现新颖的光学性能或开辟新的应用领域.依托研制的低温高分辨激光光谱和上转换量子产率等仪器,本课题组致力于稀土无机发光材料电子结构与性能研究,近年来在发光材料的控制合成、电子结构、光学性能及生物应用等方面取得了系列重要结果.这些研究有望加快实现稀土无机发光材料在生物应用的突破,实现稀土资源的高值利用.     

Host Differential Sensitization toward Color/Lifetime-Tuned Lanthanide Coordination Polymers for Optical Multiplexing

Optical multiplexing based on luminescent materials with tunable color/lifetime has potential applications in information storage and security. However, the available tunable luminescent materials reported so far still suffer from several drawbacks of low efficiency or poor stability, thus restraining their further applications. Herein, we demonstrate a strategy to develop efficient and stable lanthanide coordination polymers (LCPs) with tunable luminescence as a new option for optical multiplexing. Their multicolor emission from green to red and naked-eye-sensitive green emission with tunable lifetime (from ca. 300 to ca. 600 μs) can be controlled by host differential sensitization and energy transfer between lanthanide ions. The quantum efficiencies of developed samples range from around 20 % to 46 % and the luminescence intensity/lifetime appear quite stable in polar solvents up to ten weeks. Furthermore, with the aid of inkjet printing and concepts of luminescence lifetime imaging and time-gated imaging, we illustrate their promising applications of information storage and security in spatial and temporal domains.     

Covalent linking of near-infrared luminescent ternary lanthanide (Er(3+), Nd(3+), Yb(3+)) complexes on functionalized mesoporous MCM-41 and SBA-15

The near-infrared (NIR) luminescent lanthanide ions, such as Er(III), Nd(III), and Yb(III), have been paid much attention for the potential use in the optical communications or laser systems. For the first time, the NIR-luminescent Ln(dbm)(3)phen complexes have been covalently bonded to the ordered mesoporous materials MCM-41 and SBA-15 via a functionalized phen group phen-Si (phen-Si = 5-(N,N-bis-3-(triethoxysilyl)propyl)ureyl-1,10-phenanthroline; dbm = dibenzoylmethanate; Ln = Er, Nd, Yb). The synthesis parameters X = 12 and Y = 6 h (X denotes Ln(dbm)(3)(H(2)O)(2)/phen-MCM-41 molar ratio or Ln(dbm)(3)(H(2)O)(2)/phen-SBA-15 molar ratio and Y is the reaction time for the ligand exchange reaction; phen-MCM-41 and phen-SBA-15 are phen-functionalized MCM-41 and SBA-15 mesoporous materials, respectively) were selected through a systematic and comparative study. The derivative materials, denoted as Ln(dbm)(3)phen-MCM-41 and Ln(dbm)(3)phen-SBA-15 (Ln = Er, Nd, Yb), were characterized by powder X-ray diffraction, nitrogen adsorption/desorption, Fourier transform infrared (FT-IR), elemental analysis, and fluorescence spectra. Upon excitation of the ligands absorption bands, all these materials show the characteristic NIR luminescence of the corresponding lanthanide ions through the intramolecular energy transfer from the ligands to the lanthanide ions. The excellent NIR-luminescent properties enable these mesoporous materials to have potential uses in optical amplifiers (operating at 1.3 or 1.5 mum), laser systems, or medical diagnostics. In addition, the Ln(dbm)(3)phen-SBA-15 materials show an overall increase in relative luminescent intensity and lifetime compared to the Ln(dbm)(3)phen-MCM-41 materials, which was explained by the comparison of the lanthanide ion content and the pore structures of the two kinds of mesoporous materials in detail.     

Lanthanide‐Based Luminescent Materials for Waveguide and Lasing

Microlasers and waveguides have wide applications in the fields of photonics and optoelectronics. Lanthanide‐doped luminescent materials featuring large Stokes/anti‐Stokes shift, long excited‐state lifetime as well as sharp emission bandwidth are excellent optical components for photonic applications. In the past few years, great progress has been made in the design and fabrication of lanthanide‐based waveguides and lasers at the micrometer length scale. Waveguide structures and microcavities can be fabricated from lanthanide‐doped amorphous materials through top‐down process. Alternatively, lanthanide‐doped organic compounds featuring large absorption cross‐section can self‐assemble into low‐dimensional structures of well‐defined size and morphology. In recent years, lanthanide‐doped crystalline structures displaying highly tunable excitation and emission properties have emerged as promising waveguide and lasing materials, which substantially extends the range of lasing wavelength. In this minireview, we discuss recent advances in lanthanide‐based luminescent materials that are designed for waveguide and lasing applications. We also attempt to highlight challenging problems of these materials that obstacle further development of this field.     

白光型金属有机框架材料的最新研究进展

金属有机框架化合物（MOFs）是一类备受关注的多功能杂化材料,结构的多样性使其表现出各种发光性能。尤其是环境友好、使用寿命长、效率高的白光MOFs材料的出现为新型发光MOFs的设计和制备提供了契机。我们旨在总结白光MOFs的最新研究进展,着重对其合成方法及应用进行综述,主要包括镧系离子共掺杂、镧系元素封装或有机分子捕获等获得可调控的白光MOFs的方法及其在温度、分子和金属离子传感器等领域的潜在应用。同时,针对白光MOFs材料面临的挑战和未来发展也进行了梳理。以期引起设计和构建新型发光MOFs的研究人员的关注与兴趣。     

稀土铕、铽配合物在温度发光传感领域的研究进展

稀土发光配合物材料基于其独特的4f-4f电子跃迁表现出优异的发光性能,特别是铕和铽配合物材料,发光波长在可见光区范围内,发射谱带狭窄且尖锐(半峰宽通常小于10 nm),非常适合应用于显示设备和传感装置.同时,具备温度依赖发光性能的铕和铽配合物能够实现高灵敏度、高效的温度传感过程,使其有望用于流体动力学、航空航天、环境工...     

A multi-color and white-light emissive cucurbituril/ terpyridine/ lanthanide supramolecular nanofiber

The enhanced lanthanide white-emission in solid by cucurbituril-based supramolecular assembly may provide a new strategy for smart light-emitting materials.     

Preparation of hybrid mesoporous silica luminescent nanoparticles with lanthanide(III) complexes and their exhibition of white emission

We chose dipicolinic acid as a tridentate chelating unit featuring ONO donors to react with lanthanide(III) ions to yield tight and protective N(3)O(6) environments around the lanthanide(III) ions. We immobilized the lanthanide(III)-dipicolinic acid complexes on colloidal mesoporous silica with diameter smaller than 100 nm by a covalent bond grafting technique and obtained nearly monodisperse luminescent Eu-dpa-Si and Tb-dpa-Si functionalized hybrid mesoporous silica nanomaterials. These hybrid nanomaterials were characterized by powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, nitrogen adsorption-desorption, and photoluminescence spectroscopic techniques. The hybrid mesoporous silica nanoparticles exhibit intense emission lines upon UV-light irradiation, owing to the effective intramolecular energy transfer from the chromophore to the central lanthanide Eu(3+) and Tb(3+) ions. Furthermore, the functionalized nanomaterials can be turned to white light materials after annealing at high temperature.     

Lanthanide co-ordination frameworks: Opportunities and diversity

Significant successes have been made over recent years in preparing co-ordination framework polymers that show macroscopic material properties, but in the vast majority of cases this has been achieved with d-block metal-based systems. Lanthanide co-ordination frameworks also offer attractive properties in terms of their potential applications as luminescent, non-linear optical and porous materials. However, lanthanide-based systems have been far less studied to date than their d-block counterparts. One possible reason for this is that the co-ordination spheres of lanthanide cations are more difficult to control and, in the absence of design strategies for lanthanide co-ordination frameworks, it is significantly more difficult to target materials with specific properties. However, this article highlights some of the exciting possibilities that have emerged from the earliest investigations in this field with new topological families of compounds being discovered from relatively simple framework components, including unusual eight, seven and five-connected framework systems. Our own research, as well as others, is leading to a much greater appreciation of the factors that control framework formation and the resultant observed topologies of these polymers. As this understanding develops targeting particular framework types will become more straightforward and the development of designed polyfunctional materials more accessible. Thus, it can be seen that lanthanide co-ordination frameworks have the potential to open up previously unexplored directions for materials chemistry. This article focuses on the underlying concepts for the construction of these enticing and potentially highly important materials.     

New nematogenic β-diketones for synthesis of lanthanidomesogens

A series of new β-diketones containing in their structure cyclohexane and benzene ring was obtained. The effect of the terminal substituents in the molecules of β-diketones on their liquid crystal and optical properties was studied. The absorption spectra of all β-diketones practically do not overlap with the emission spectrum of polymer PFO but have good overlapping with that of PVC. The obtained compounds are promising ligands for synthesis of liquid crystal adducts of lanthanide β-diketonates with the Lewis bases, polyfunctional luminescent materials.     

Ln3+‐Mediated Self‐Assembly of a Collagen Peptide into Luminescent Banded Helical Nanoropes

Design of biomimetic peptides to achieve the desired properties of natural collagen has much potential to build functional biomaterials. A collagen‐peptide/Ln³⁺ system has been constructed and self‐assembled to form helical nanoropes with a distinct periodic banding pattern characteristic of natural collagen. The fully reversible self‐assembly is specifically mediated by lanthanide ions, but not by other commonly used divalent metal ions. Lanthanide ions not only provide an external biocompatible stimulus of the assembly, but also play as a functional unit to endow the assembled materials with easily tunable photoluminescence. To our knowledge, this is the first report of collagen‐peptide‐based materials with exquisite nanorope structure and excellent photoluminescent features. These novel luminescent nanomaterials may have great potential in cell imaging, medical diagnostics, and luminescent scaffolds for cell cultivation.     

Loading Photochromic Molecules into a Luminescent Metal–Organic Framework for Information Anticounterfeiting

Stimuli‐responsive photoluminescent materials have attracted considerable attention owing to their potential applications in security protection because the information recorded directly in materials with static luminescent outputs are usually visible under either ambient or UV light. Herein, we realize reversible information anticounterfeiting by loading a photoswitchable diarylethene derivative into a lanthanide metal–organic framework (MOF). Light triggers the open‐ and closed‐form isomerization of the diarylethene unit, which respectively regulates the inactivation and activation of the photochromic FRET process between the diarylethene acceptor and lanthanide donor, resulting in reversible luminescence on–off switching of the lanthanide emitting center in the MOF host. This photoresponsive host–guest system allows for reversible multiple information pattern visible/invisible transformation by simply alternating the exposure to UV and visible light.     

Tunable white-light emission of lanthanide(Ⅲ) hybrid material based on hectorite

In this work, we present novel trivalent lanthanide ions(Ln~(3+))-based luminescent hybrid materials, in which the organic ligands are covalently grafted on the hectorite templates and the Ln~(3+) ions can be well immobilized by the ligands through coordination bond. The hybrid materials exhibit tunable emission colors by varying the molar ratio of Eu~(3+) to Tb~(3+), and the one with Eu~(3+):Tb~(3+)=1:1 exhibits excellent coordinate of(0.327, 0.328) located in the "white region" of the CIE 1931 chromaticity diagram(under300 nm UV illumination). These properties make the hybrid composites suitable for fabricating optoelectronic devices such as full-color displays and white LED.