共查询到20条相似文献,搜索用时 15 毫秒
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A kind of precursor molecule (abbreviated as EPDA–APMS) was synthesized by means of the amidation reaction of 5-ethylpyridine-2,3-dicarboxylic acid (EPDA) with a crosslinking molecule (3-aminopropyl)trimethoxysilane (APMS). Then the hybrid materials were obtained by reaction of this kind of monomer (EPDA–APMS), tetraethoxysilane (TEOS) and Tb(NO3)3·6H2O by an in-situ sol-gel process, resulting in a novel molecular hybrid material (named as Tb–EPDA–APMS) with double chemical bonds (Tb–O coordination bond and Si–O covalent bond). Ultraviolet absorption, phosphorescence, and fluorescence spectra were applied to characterize the photophysical properties of the obtained hybrid material. The strong luminescence of Tb3+ substantiates optimum energy match and effective intramolecular energy transfer between the triplet state energy of modified ligand bridge and emissive energy level of Tb3+. 相似文献
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Summary. A kind of precursor molecule (abbreviated as EPDA–APMS) was synthesized by means of the amidation reaction of 5-ethylpyridine-2,3-dicarboxylic acid (EPDA) with a crosslinking molecule (3-aminopropyl)trimethoxysilane (APMS). Then the hybrid materials were obtained by reaction of this kind of monomer (EPDA–APMS), tetraethoxysilane (TEOS) and Tb(NO3)3·6H2O by an in-situ sol-gel process, resulting in a novel molecular hybrid material (named as Tb–EPDA–APMS) with double chemical bonds (Tb–O coordination bond and Si–O covalent bond). Ultraviolet absorption, phosphorescence, and fluorescence spectra were applied to characterize the photophysical properties of the obtained hybrid material. The strong luminescence of Tb3+ substantiates optimum energy match and effective intramolecular energy transfer between the triplet state energy of modified ligand bridge and emissive energy level of Tb3+. 相似文献
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Ulrich Schubert 《Journal of Sol-Gel Science and Technology》2003,26(1-3):47-55
Organically substituted metal alkoxides can be prepared by reaction of the parent alkoxides with complexing organic compounds. The chemical and structural consequences of such substitutions are discussed in this article. Examples are given showing how functional organic moieties, such as polymerizable groups, can be incorporated into sol-gel materials via the complexing ligands. Major structural differences between silica-based and metal-based hybrid materials originate from the different charge/coordination number ratios of silicon and most metals. This results in a high tendency for the molecular building blocks to aggregate. In many cases, metal oxide clusters are formed which are capped by the organic ligands. Such surface-modified clusters are themselves very valuable condensed matter units for materials syntheses. 相似文献
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Jade Poisson Prof. Dr. Zachary M. Hudson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(32):e202200552
Surface-tethered polymers are unique molecular architectures that have been recently used in advanced sensors, electronics and biomedical applications. However, techniques for characterizing these materials in their surface-tethered form remain limited. The incorporation of luminescent functionality into these materials has enabled new characterization methods, while also unlocking new applications in optoelectronics, stenography and sensing. Micron-scale photolithography techniques have recently enabled the preparation of high-resolution patterns, as well as architectures with unique photophysical properties. Herein, we provide an overview of the techniques used to prepare luminescent polymer brush materials and their applications in stimuli-responsive sensors, cell adhesion materials, and optoelectronics. We also provide our perspective on the promising future uses of surface-tethered polymers, as well as the short-term challenges and opportunities in the field. 相似文献
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Yingxiang Duan Qian Zhao Yanhua Yang Jinyang Zhang Xuan Tao Yingzhong Shen 《Journal of heterocyclic chemistry》2019,56(4):1464-1471
Five new materials based on pyrazole derivatives have been synthesized and characterized as organic light‐emitting devices. This report presents a novel approach to combine pyrazole with aromatic hydrocarbons via methylene. The formed molecules exhibited twisted structures, which resulted in high glass transition temperatures (Tg), which ranged from 83.0 to 101.1°C. They also had high optical band gaps (Eg); most of their optical band gaps are determined by the absorption edge technique as 3.43 to 3.66 eV, evaluated photophysical properties of these synthesized novel chromophores, the optical properties such as maximum absorption and emission wavelengths (λ; nm), molar extinction coefficients (ε; cm?1·M?1), Stokes' shifts (ΔλST; nm), and quantum yields (φF). These compounds exhibited intense absorption bonds between 230 and 350 nm, and the effect of solvent polarity on emission of these pyrazole derivatives was also studied. In addition, they showed blue fluorescence in different solvents and bathochromic shift with the increase in the solvent polarity. 相似文献
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PVK与新型D-π-A分子掺杂体系的能量转移及发光性质 总被引:1,自引:0,他引:1
通过对PVK与4种新型D-π-A分子(分别简写为CKD, TKD, PKD, NKD)掺杂体系的吸收光谱、激发光谱和光致发光光谱的研究, 分析了掺杂体系的光致发光特性和能量转移现象. 制备了结构为ITO/PEDOT/PVK∶D-π-A ω/Alq3/Al的电致发光器件, 研究了掺杂体系的电致发光性能. 研究结果表明, 通过改变D-π-A分子中不同给电子能力的电子给体, 可以调控其带隙, 进而实现对D-π-A分子发光峰位的调节; 给电子基团空间立构效应越高, 其荧光量子效率越高. 在掺杂体系的光致发光和电致发光中, PVK与D-π-A分子之间都发生了有效的能量转移, 通过调节PVK与D-π-A分子的比例, 可以调节掺杂体系的发光性能. 当TKD在PVK中的掺杂质量分数为6%时, 电致发光器件发光亮度为729.1 cd/m2时, 发光效率达到1.75 cd/A. 相似文献
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Mechanofluorochromic or piezochromic fluorescence chemistry involves the switching and tuning of the luminescent properties of solid‐state materials induced by exogenous forces, such as grinding, shearing, compression, tension, and so forth. Up until now, most reported mechanochromic systems, including liquid crystals, organic molecules, organometallic compounds, polymers, and dye‐doped polymers, have displayed reversible two‐color changes, which arise from either supramolecular or chemical structure transformations. However, fluorescent materials that undergo mechanically induced multicolor changes remain rare; this Minireview is focused on such materials. Topics are categorized according to the different applied forces that are required to induce the multicolor change, including mechanical control of either the supramolecular structures or the chemical structures, and mechanical control of both the supramolecular structures and chemical structures. 相似文献
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Our work on the characteristics of organoboron‐containing polymers is reviewed. The electronic interaction and correlation involving organoboron complexes are responsible for the optical and electric properties of the polymers. To understand the origins of these properties and apply them to the next generation of new materials, we have gathered not only fundamental knowledge on the electronic states and behaviors of each organoboron complex in the polymers but also on the functions of the polymers in devices. In this article, we introduce our findings obtained from a series of studies on polymers involving cyclodiborazane, quinolate, diketonate, dipyrromethene, pyrazabole, and carborane complexes. In particular, there is a focus on results from recent work. 相似文献
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Prof. Dr. Huanrong Li Man Li Dr. Yu Wang Prof. Dr. Wenjun Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(33):10392-10396
The spectroscopic behavior of ionic Eu3+ or Tb3+ complexes of an aromatic carboxyl‐functionalized organic salt as well as those of the hybrid materials derived from adsorption of the ionic complexes on Laponite clay are reported. X‐ray diffraction (XRD) patterns suggest that the complexes are mainly adsorbed on the outer surfaces of the Laponite disks rather than intercalated within the interlayer spaces. Photophysical data showed that the energy‐transfer efficiency from the ligand to Eu3+ ions in the hybrid material is increased remarkably with respect to the corresponding ionic complex. The hybrid material containing the Eu3+ complex shows bright red emission from the prominent 5D0→7F2 transition of Eu3+ ions, and that containing the Tb3+ complex exhibits bright green emission due to the dominant 5D4→7F5 transition of Tb3+ ions. 相似文献
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稀土磷酸盐发光材料的微波合成 总被引:5,自引:0,他引:5
稀土磷酸盐发光材料的微波合成徐文国,田一光,刘淼,刘海堂,方光华,庞文琴(吉林大学化学系,环境科学系,长春,130023)关键词微波合成,稀土磷酸盐,微晶玻璃,玻璃态,发光材料稀土磷酸盐发光材料的研究是当前材料科学的热门研究课题。它们一般通过高温固相... 相似文献
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非线性光学材料的分子设计研究 总被引:6,自引:1,他引:6
非线性光学研究应用电磁场和各种材料的相互作用, 产生新的电磁场, 改变频率, 相或其它物理性质. 本文介绍了非线性光学材料分子设计的原理, 并以共轭长链分子和碳笼及其衍生物为例报道了我们在这方面的研究工作. 相似文献
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稀土配合物Tb(Phen)x(Bipy)(4-x)(NO3)3(x=4,3,2,1,0)(1×10-3mol·L)溶液中,当配体邻菲罗琳(Phen)和2,2′ 联吡啶(Bipy)共存同一铽的配合物中时,Tb3+的特征发光被敏化,其中Tb(Phen)3(Bipy)(NO3)3的荧光强度是最强,Tb(Bipy)4(NO3)3的荧光强度是最弱。Tb3+在(CH3)3Si MCM 41 Tb(Bipy)4(NO3)3中的特征发光强度最强,而在MCM 41 Tb(Phen)3(Bipy)(NO3)3和(CH3)3Si MCM 41 Tb(Phen)3(Bipy)(NO3)3中的发光变得很弱。当客体分子Tb(Phen)4(NO3)3和Tb(Bipy)4(NO3)3被组装到疏水的主体分子筛(CH3)3Si MCM 41孔道里要比组装到亲水的分子筛MCM 41孔道里的发光要强;当客体分子是Tb(Phen)3(Bipy)(NO3)3和Tb(Phen)2(Bipy)2(NO3)3时,它们的发光情况与前一种情况刚好相反即亲水的极性内腔环境有利于客体分子的发光;平行的荧光寿命试验的结论也是一致的。说明在不同的超分子体系中,疏水和亲水的环境都有可能利于客体分子的发光。在(CH3)3Si MCM 41 Tb(Phen)(Bipy)3(NO3)3中的配体的荧光强度要比在MCM 41 Tb(Phen)(Bipy)3(NO3)3中的强;而Tb3+的特征荧光强度的情况刚好相反。MCM 41 Tb(Phen)(Bipy)3(NO3)3和(CH3)3Si MCM 41 Tb(Phen)(Bipy)3(NO3)3有明显的双指数衰减,双指数衰减拟合所得荧光寿命分别为168.8,641.1μs和73.2,5 相似文献