稀土铽超分子纳米功能材料的荧光性质比较

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     

铕(Ⅲ)荧光增敏体系在微乳液中的发光性质和荧光衰减动力学研究

利用稳态和瞬态光谱方法研究了不同铕离子发光体系中各种因素对铕离子发光性质的影响 .通过吸收和激发光谱的变化分析了稀土离子 Gd3 +对 Eu3 +增敏机理 ,并从荧光衰减动力学角度证明了主配体噻吩甲酰三氟丙酮 ( TTA)、协配体邻啡咯啉 ( Phen)、稀土离子 Gd3 +和表面活性剂 TX-1 0 0对铕离子发光的增敏作用 .4种发光体系 Eu3 +/Gd3 +/TTA/Phen/TX-1 0 0 ,Eu3 +/TTA/Phen/TX-1 0 0 ,Eu3 +/Gd3 +/TTA/Phen和Eu3 +/Gd3 +/TTA/TX-1 0 0中铕离子 5D0 态的发光寿命依次为 980 >6 70 >4 0 0 >2 6 0 μs,而且存在铕离子 5D1到 5D0 的传能过程 .在发光越强的体系中 ,5D1 的衰减越慢 ,相应地 5D0 的上升时间也就越长 .研究结果表明 ,在最佳发光体系中既存在分子内的能量转移 ,又存在分子间的能量传递     

杂化材料Eu(Phen)2Cl3/MCM-41的荧光性能及热稳定性研究

采用超声波辅助,将稀土配合物Eu(Phen)2Cl3装入中孔分子筛MCM-41孔道,合成了不同组装量的杂化材料Eu(Phen)2Cl3/MCM-41。运用XRD、N2吸附-脱附、FTIR、荧光光谱等手段对杂化材料进行了表征,研究表明稀土配合物已进入分子筛孔道,且随着配合物嵌入量的增加,杂化材料的荧光发射也逐渐增强。当Eu(Phen)2Cl3的组装量达到饱和(7.17%)时,其荧光强度最大。与纯配合物Eu(Phen)2Cl3相比,Eu(Phen)2Cl3/MCM-41的热稳定性提高了约100°C。     

双核双配体稀土配合物Tb1-xEux(TTA)3Phen的合成及光学性能研究

合成了系列铕铽双核稀土有机稀土配合物Tb1-xEux（TTA）3Phen，通过差热．热重分析、XRD、红外光谱、紫外光谱和荧光光谱等测试手段研究了配合物的组成、结构和发光性质。由紫外可见光谱可以看出，稀土有机配合物的吸收峰主要来自有机配体HTrA和1，10-Phen；差热-热重分析证明，稀土有机配合物热稳定性较好。荧光光谱和电致发光表明，铽对铕配合物的发光有协同作用。在该系列配合物中，不仅有机配体可以将吸收的能量传递给发光的铕离子使其发光，而且铽离子也可将其吸收的能量通过分子内能量传递给铕离子，增强铕的发光强度。同时就双核稀土有机配合物光致发光和电致发光的特性及掺杂体系的能量传递过程进行了讨论。     

稀土三元配合物粉末和凝胶共发光效应的光声光谱研究

合成了Eu(TTA)3·Phen和Eu0.8Y0.2(TTA)3·Phen固体配合物微晶粉末及其掺杂的SiO2凝胶样品.在300～800nm测定并解释了其光声光谱.在配体吸收处,Eu0.8Y0.2(TTA)3@Phen的光声强度低于Eu(TTA)3@Phen的光声强度;而对于配合物掺杂的凝胶样品,则情况相反.Y3+的引入改变了配合物的弛豫过程,且配合物在粉末和凝胶状态下,弛豫历程不尽相同.结合荧光光谱研究了标题化合物的发光特性,并建立了能量传递模型.     

稀土—β—二酮配合物LB膜和三线态能量转移研究

在胶束体系中，Eu3+的发光强度可通过加入La3+－TTA－Phen（TTA：噻吩甲酰三氟丙酮；Phen：邻菲咯琳）而大大增强，这种发光增强作用被认为是由配体TTA经过三线态向EU3+的共振能级转移能量所致[1]．本文利用LB技术将这种Eu3+增强的发光转移到有序排列的LB膜中，研究了La（TTA）3Phen对Eu3+的发光增强作用，并用LB方法探讨了这种分子间的能量转移过程，发现这种能量转移距离小于3um，属经由三线态的短程交换能量转移过程．同时，用荧光光谱和低角X衍射对这种混合稀土配合物LB膜进行了表征．1实验部分配合物La（TTA）3Phen和Eu…     

含稀土铕配合物三维有序大孔材料的制备及其荧光性能

采用物理吸附的方法将稀土配合物嵌入三维有序大孔聚合物材料的孔内,组装了发光性能良好的含邻菲罗林-铕配合物的三维有序大孔聚合物材料(3DOM/Eu(Phen)2).并通过扫描电镜、红外光谱和荧光光谱对3DOM/Eu(Phen)2组装体进行了表征.结果表明:组装体的结构保持了三维有序大孔材料的结构特征,在紫外灯的照射下,发出稀土离子的特征谱线,与纯配合物相比,其激发光谱发生蓝移,荧光寿命延长.     

铕-3-(2-萘甲酰基)-2-苯基苯并二氢吡喃-4-酮-邻菲罗啉配合物的合成及荧光性能研究

为了探讨2,3-二氢黄酮类化合物在发光材料方面的应用,首先合成了2,3-二氢黄酮类衍生物[3-(2-萘甲酰基)-2-苯基苯并二氢吡喃-4-酮(L)]配体,然后利用Eu(III)与此配体和水/邻菲罗啉(Phen)反应得到两种新型的红色荧光配合物。运用元素分析、红外光谱与荧光光谱等手段对相关物质进行了系统的表征。表征结果表明:两个新配合物的组成分别为Eu(L)3·2H2O和Eu(L)3·Phen;荧光光谱研究显示,两种配合物的配体能将吸收的能量有效地传递给铕离子,从而使配合物发射出强的铕离子的特征荧光,且两个配合物Eu(L)3·2H2O和Eu(L)3·Phen均以5D0→7F2跃迁的荧光发射最强。得到了两种新的高效的红色荧光材料。     

稀土配合物自组织结构的荧光显微镜观察

在气/液界面上用荧光显微镜(fluorescence microscopy, 缩写FM)实时研究了纯Eu(TTA)₃Phen单层膜及其与硬脂酸的混合膜在不同亚相上压缩过程中的形貌变化. 结果表明, 复合亚相是稀土配合物稳定存在的基本前提. 稀土配合物由液态扩张相变为液态凝聚相的过程对应于表面压-分子面积等温线(π - A曲线)上的平台区. 纯配合物单层膜中, Eu(TTA)₃Phen形成无序排列的短条状微畴(domain); 混合膜中, 硬脂酸分子先发生相变形成具有电场梯度的微畴, 诱导具有偶极矩的铕配合物分子自组织形成荧光环. 揭示了二维有序膜体系中分子间相互作用对微畴形貌的影响.     

一种新型稀土配合物Eu(TTA)2(N-HPA)Phen的发光特性研究

合成了一种新的含有3个配体的稀土配合物Eu（TTA）2（N-HPA）Phen（TTA-噻吩甲酰基三氟丙酮，N—HPA=N-苯基邻氨基苯甲酸，phen=邻菲咯啉）。将稀土配合物作为掺杂物与基质PVK按照不同质量比混合共溶，旋涂成膜。通过荧光光谱，分析了薄膜的发光特性，并将其应用于有机电致发光。研究了PVK和Eu（TTA）2（N—HPA）Phen之间的能量传递，并且制备了发光层为PVK：Eu（TTA）2（N—HPA）Phen，结构为ITO／PVK：Eu（TrA）2（N—HPA）Phen／BCP／Alq3／Al的多层器件，发现改变PVK和稀土配合物的掺杂比，可以不同程度地抑制PVK的发光，最终得到纯的Eu^3＋的红色发光。实验结果证明，在PVK：Eu（TTA）2（N—HPA）Phen=5：1的质量比下，从PVK到稀土配合物之间存在充分的能量传递。     

Luminescence of Nanosized Supramolecular Material of Mesoporous Molecular Sieve and Samarium （Ⅲ） Complex

IntroductionThe synthesis of mesoporous silica has greatlyexpanded the possibilities for the design of the porestructure materials[1] . Because of their large sur-face areas and porosity,these materials have greatpotential application in environmental and industri-al fields.A greatmany significant advanced resultshave been achieved in this field including the syn-theses of the related materials[2— 4] ,the develop-ment of the novel properties[5— 8] ,the discovery ofnew theories on synthetic c…     

Eu(TTA)_3/MCM-41介孔复合体的溶胶凝胶法组装

利用溶胶 凝胶法将稀土配合物Eu(TTA) 3 组装到MCM 41介孔分子筛的孔道中 ,并初步认定客体分子Eu(TTA) 3 是以加合物形式包裹于表面活性剂胶束中。该法制得的介孔复合体Eu(TTA) 3/MCM 41,用XRD、HRTEM技术证实具有短程有序的、规整的六方介孔结构和大小分布均匀的纳米晶粒。对其光致发光和荧光寿命的研究发现 :与乙醇溶液中相比 ,Eu3 的荧光寿命没有发生改变 ,但Stokes位移却明显增大 ;复合体中 ,能量是从主体MCM 41传递到客体Eu(TTA) 3 上。     

(MCM-41)-La_2O_3纳米复合材料的制备、表征及光学性质

借助水热法,以正硅酸乙酯为硅源,十六烷基三甲基溴化铵为模板剂,在碱性条件下制备了纳米MCM-41分子筛。通过固相热扩散法将La2O3组装到MCM-41介孔孔道中,制备出含La2O3不同浓度的(MCM-41)-La2O3主-客体纳米复合材料。采用化学分析、粉末XRD、FTIR、77K低温N2吸附-解吸附、固体扩散漫反射吸收光谱、拉曼光谱、扫描电镜和发光光谱对主-客体复合材料进行表征。粉末XRD结果表明,La2O3组装到MCM-41分子筛的孔道后并未破坏分子筛骨架,在所制备的(MCM-41)-La2O3主-客体纳米复合材料中MCM-41骨架结构仍然具有较高的有序性,并且,随着植入客体材料浓度的增加复合材料的有序度有所降低。红外光谱表明所制备的纳米复合材料主体分子筛骨架完好;低温氮气吸附-解吸附技术表明La2O3已经部分地占据了MCM-41分子筛孔道,导致分子筛的比表面积和孔体积都有所降低;固体扩散漫反射吸收光谱表明吸收光谱的吸收峰发生了蓝移现象,并表现出量子限域效应,说明La2O3已经组装到了MCM-41分子筛的孔道中;拉曼光谱表明所制备的复合材料没有出现新的特征峰,表明La2O3已经组装到了MCM-41分子筛的孔道中;扫描电镜表明(MCM-41)-La2O3样品的外观非常规整,主要呈现的是球状结构,La2O3含量为10%时,(MCM-41)-La2O3的平均粒径为(114±10)nm。发光光谱研究结果表明,所制备的复合材料(MCM-41)-La2O3样品在396nm处具有较好的发光性质,因而具有作为发光材料潜在应用前景。     

Study on the fluorescence and thermal stability of hybrid materials Eu(Phen)2Cl3/MCM-41

A series of luminescent hybrid materials Eu (Phen)₂Cl₃/MCM-41 that the different assembled mass of Eu(Phen)₂Cl₃ included into the channels of MCM, have been synthesized by combining ultrasound technology. The properties of the hybrid materials were characterized by XRD(X-ray Diffraction), N₂-adsorption-desorption, FT-IR and luminescence spectrum. The results show that the rare-earth compounds had been loaded into the holes of mesoporous material MCM-41. The luminescence intensities of the hybrid materials were improved as the increase of the loading concentration of the rare-earth complexes. The hybrid material has the maximal luminescence intensity when it reached the saturated loading concentration (7.17%). To compare with the pure rare-earth complex, the thermal stability of the hybrid materials were enhanced by about 100°C. __________ Translated from Chemical Research and Application, 2008, 20(1) (in Chinese)     

Synthesis, photophysical and oxygen-sensing properties of a novel Eu complex incorporated in mesoporous MCM-41

A novel Eu³⁺ complex of Eu(DPIQ)(TTA)₃ (DPIQ=10H-dipyrido [f,h] indolo [3,2-b] quinoxaline, TTA=2-thenoyltrifluoroacetonate) was synthesized and encapsulated in the mesoporous MCM-41, hoping to explore an oxygen-sensing system based on the long-lived Eu³⁺ emitter. The Eu(DPIQ)(TTA)₃/MCM-41 composites were characterized by infrared spectra (IR), ultraviolet-visible (UV-vis) absorption spectra, small-angle X-ray diffraction (SAXRD), luminescence intensity quenching upon various oxygen concentrations, and fluorescence decay analysis. The results indicated that the composites exhibited the characteristic emission of the Eu³⁺ ion and the fluorescence intensity of ⁵D₀-⁷F₂ obviously decreased with increasing oxygen concentrations. The oxygen sensing properties of the composites with different loading levels of Eu(DPIQ)(TTA)₃ complex were investigated. A sensitivity of 3.04, a short response time of 7 s, and good linearity were obtained for the composites with a loading level of 20 mg/g. These results are the best reported values for optical oxygen-sensing materials based on Eu³⁺ complexes so far.     

Thiocyanates of rare-earth elements with tetramethylphenanthroline

Molecular [M(NCS)₃(H₂O)(Me₄Phen)₂] · (Me₄Phen) · 0.75EtOH and anionic [H(Me₄Phen)][М(NCS)₄(Me₄Phen)₂] complexes are synthesized using thiocyanates М(NCS)₃ · 6H₂O (M = Y, Eu, Tb) and 3,4,7,8-tetramethyl-1,10-phenanthroline (Me4Phen). The complexes are characterized by IR spectroscopy and elemental, X-ray phase, and X-ray diffraction analyses (CIF files CCDC no. 1498178–1498184). The thermoanalytical study shows that the solvate molecules Me₄Phen are localized in the internal coordination sphere of the molecular complexes at 195–250°C. The magnetic behavior of the Eu and Tb complexes is governed by the nature of the Ln ion.     

2,2′-Dipyridyl and 1,10-phenanthroline in the synergetic extraction of Eu3+

The thermodynamics of the extraction of Eu³⁺ by thenoyltrifluoroacetone (HTTA) and by mixtures of HTTA and bidentate amine bases such as 2,2-dipyridyl (Dipy) and 1,10-phenanthroline (Phen) in benzene from an aqueous phase fixed to 0.1M ionic strength (NaClO₄), pH 3.9, has been investigated. Phenanthroline forms both the Eu(TTA)₃·Phen and Eu(TTA)₃·2Phen species, which are much stronger than the dipyridyl complexes. The diluent effect on the extraction is also studied.     

Determination of fluoroquinolone antibiotics through the fluorescent response of Eu(III) based nanoparticles fabricated by layer-by-layer technique

The present work introduces the determination of fluoroquinolone antibiotics (FQs) in aqueous solutions through the fluorescent response of Eu(TTA)₃ and [Eu(TTA)₃1] (TTA⁻ and 1 are thenoyltrifluoroacetonate and phosphine oxide derivative) complexes encapsulated into the polyelectrolyte capsules fabricated through layer-by-layer deposition of poly(sodium 4-styrenesulfonate) (PSS) and polyethyleneimine (PEI). The variation of luminescent core, polyelectrolyte deposition and concentration conditions reveals two modes of fluorescent response on FQs of diverse structure namely the sensitization and quenching of Eu(III) centered luminescence. The obtained regularities reveal the ternary complex formation and the ligand exchange occurring at the interface of polyelectrolyte coated [Eu(TTA)₃1] based colloids as the reasons of the diverse fluorescent response of Eu(III) centered luminescence on FQs. The factors affecting the fluorescent response have been revealed, which are: the content of luminescent core, the mode of polyelectrolyte deposition, concentration and structure of FQs. The discrimination of moxifloxacin and lomefloxacin from levofloxacin, ofloxacin, difloxacin, perfloxacin through the quenching of Eu(III) luminescence in PSS-[Eu(TTA)₃1] colloids has been revealed.     

Fluorescence microscopy observation of self-organized microstructure formed by a rare earth compound

The morphologies of monolayers containing Eu(TTA)3Phen (TTA=thenoyltrifluoroace-tone, Phen = 1, 10-phenanthroline) were studied at the air/liquid interface on different subphases by fluorescence microscopy (FM). The composite subphase was the basic premise for the stable existence of the rare earth compound at air/liquid interface. The process that rare earth compound phase changes from liquid expanded state to liquid condensed state corresponded to a plateau in the π-A isotherm. In the pure Eu(TTA)3Phen monolayer, rod domains of Eu(TTA)3Phen formed and packed with no order. In the mixed monolayers with stearic acid (SA), phase transition of SA occurred first and formed domains with an electric gradient field, which induced the rare earth compound to form luminescent ring domains. Influence of intermolecular interaction on the self-organized microstructure was revealed.     

介孔氧化硅孔径尺寸对Eu(Ⅲ)配合物的影响

分别以十六烷基三甲基溴化铵(CTAB)和聚乙氧基-聚丙氧基-聚乙氧基三嵌段共聚物(P123)为模板剂、正硅酸乙酯(TEOS)为硅源，采用水热法合成了有序介孔分子筛MCM-41和SBA-15。选择Eu(DBM)₃phen为客体，有序介孔氧化硅MCM-41和SBA-15为载体，分别在氯仿中进行分子组装，制备出具有较强发光性能的介孔复合材料Eu(DBM)₃phen/APTES-MCM-41(EAM)和Eu(DBM)₃phen/APTES-SBA-15(EAS)。采用XRD、TEM、N₂吸附-脱附和荧光光谱等对产物的结构与性能进行了分析。结果表明，Eu(DBM)₃phen组装进有序介孔氧化硅的孔道中后，发光纯度提高。而且孔径越小，发光纯度越高。选用较大孔径的SBA-15为载体，在不显著影响发光纯度的同时，可以获得较高的发光强度。