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.     

稀土超分子纳米功能材料的组装及其荧光性质比较

本文在无水乙醇中制备了铕的四元、三元和二元系列配合物,当配体Phen和TTA共存时,协同发光效应使得Eu(Phen)2(TTA)2的荧光最强,在铕配合物和纳米级介孔分子筛MCM－41或（CH3）3Si-MCM-41组成的超分子发光体系中,主体分子筛的疏水孔道环境有利于客体铕配合物的发展,说明主客体之间的相互作用会对复合的超分子发光材料的荧光性质产生影响。     

High‐Performance Oxygen Sensors Based on EuIII Complex/Polystyrene Composite Nanofibrous Membranes Prepared by Electrospinning

An optical oxygen sensor based on an Eu^III complex/polystyrene (PS) composite nanofibrous membrane is prepared by electrospinning. The emission intensity of [Eu(TTA)₃(phencarz)] (TTA=2‐thenoyltrifluoroacetonate, phencarz=2‐(N‐ethylcarbazolyl‐4)imidazo[4,5‐f]1,10‐phenanthroline) decreases with increasing oxygen concentration, and thus the [Eu(TTA)₃ (phencarz)]/PS composite nanofibrous membranes can be used as an optical oxygen‐sensing material based on emission quenching caused by oxygen. Elemental analysis, UV/Vis absorption spectra, scanning electron microscopy (SEM), fluorescence microscopy, luminescence‐intensity quenching Stern–Volmer plots, and excited‐state decay analysis are used to characterize the obtained oxygen‐sensing materials. A high sensitivity (I_N2/I_O2) of 3.38 and short response and recovery times (t_↓=5.0, t_↑=8.0 s) are obtained. These results are the best values reported for oxygen sensors based on Eu^III complexes. The high surface area‐to‐volume ratio and porous structure of the electrospun nanofibrous membranes are taken to be responsible for the outstanding performance.     

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.     

LB膜中稀土配合物分子间能量转移研究

有关LB膜中的Forst。r型共振能量转移已有不少报导，这种能量转移一般可发生在给体（D）和受体（川两者相距50－100A以上．所以，可以用F0rS比r公式对临界转移距离进行计算h－’1．而对LB膜中涉及三线态的分子间能量转移报导则不多见，此类能量转移是发生在6－15A之间．Yalnamo     

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…     

Synthesis, characterization, and luminescence properties of the ternary europium complex covalently bonded to mesoporous SBA-15

A novel mesoporous SBA-15 type of hybrid material (phen-SBA-15) covalently bonded with 1,10-phenanthroline (phen) ligand was synthesized by co-condensation of tetraethoxysilane (TEOS) and the chelate ligand 5-[N,N-bis-3-(triethoxysilyl)propyl]ureyl-1,10-phenanthroline (phen-Si) in the presence of Pluronic P123 surfactant as a template. The preservation of the chelate ligand structure during the hydrothermal synthesis and the surfactant extraction process was confirmed by Fourier transform infrared (FTIR) and (29)Si MAS NMR spectroscopies. SBA-15 consisting of the highly luminescent ternary complex Eu(TTA)(3)phen (TTA = 2-thenoyltrifluoroacetone) covalently bonded to a silica-based network, which was designated as Eu(TTA)(3)phen-SBA-15, was obtained by introducing the Eu(TTA)(3).2H(2)O complex into the hybrid materials via a ligand exchange reaction. XRD, TEM, and N(2) adsorption measurements were employed to characterize the mesostructure of Eu(TTA)(3)phen-SBA-15. For comparison, SBA-15 doped with Eu(TTA)(3).2H(2)O and Eu(TTA)(3)phen complexes and SBA-15 covalently bonded with a binary europium complex with phen ligand were also synthesized, and were named SBA-15/Eu(TTA)(3), SBA-15/Eu(TTA)(3)phen, and Eu-phen-SBA-15, respectively. The detailed luminescence studies on all the materials showed that, compared with the doping sample SBA-15/Eu(TTA)(3)phen and binary europium complex functionalized sample Eu-phen-SBA-15, the Eu(TTA)(3)phen-SBA-15 mesoporous hybrid material exhibited higher luminescence intensity and emission quantum efficiency. Thermogravimetric analysis on Eu(TTA)(3)phen-SBA-15 demonstrated that the thermal stability of the lanthanide complex was evidently improved as it was covalently bonded to the mesoporous SBA-15 matrix.     

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.     

噻吩甲酰三氟丙酮-酰基吡唑啉酮-邻菲咯啉合铕(Ⅲ)四元配合物的合成和表征

A novel chelate Eu(TTA)2(PMTBBP)Phen, which contained ligand 1-pheny-3-methyl-4-(4′-t-butylbenzoyl)-5-pyrazolone (HPMTBBP), 4,4,4-trifluro-1-(2-thienyl)-1, 3-butandione (HTTA) and phenanthroline(Phen), was synthesized. Its chemical structure was elucidated by IR, UV, 1H NMR,MS, DSC and elementary analysis. The influence of acylpyrazolone on fluorescent intensity of the new chelate was studied. The results showed that Eu (TTA)2 (PMTBBP)Phen had more excellent PL properties and better film formation than that of Eu(TTA)3Phen.     

Red Mechanoluminescence and Photoluminescence from Novel Europium Complexes

IntroductionMechanoluminescence(ML)islightemissioncausedbymechanicalforcesuchasgrinding,cuttingandsoon.AlthoughsomeofinorganicandorganicmolecularsolidsshowML,theMLmechanismhasnotbeenclearlyelucidatedyetl-4.The'compound,whichshowsallofML,photoluminescence(PL)andelectroluminescence(EL)properties,hasneverbeenreported.Recently,organiceuropium-compIexeshaveattractedsignificantinterestforthedevelopmentofELdevices5-'.ItisconsideredthateuropiumcomplexesareoneofthebestredELmaterialsduetotheirgo…     

pH-sensitive fluorescent sensors based on europium(III) complexes

New europium(III) complexes Eu(TTA)(2)-DSQ and Eu(TTA)(3)-DR1 were designed and synthesized as new fluorescent pH probes (where HDSQ = 5-(dimethylamino)-N-(4-(2-((8-hydroxyquinolin-2-yl)methylene)hydrazinecarbonyl)phenyl)naphthalene-1-sulfonamide, DR1 = N(1)-(4-(dimethylamino)benzylidene)-N(2)-(rhodamine-6G) lactamethylene-diamine and TTA = thiophentrifluoroacetone). Eu(TTA)(2)-DSQ exhibited high sensitivity in monitoring pH changes in neutral aqueous solution with negligible background fluorescence. Eu(TTA)(3)-DR1 comprised a green light emitting Rhodamine 6G fluorophore and a Eu(III) moiety as the origin of red light. These pH-sensitive emitter components have pK(a) values of 5.0 and 7.2 respectively, and exhibit isolated protonated steps within one molecule. Luminescence titrations demonstrate that Eu(TTA)(3)-DR1 was able to detect pH values at both near neutral pH and acidic pH ranges, and was also able to detect pH in both cultured cells and in vivo.     

Synthesis and photoluminescence properties of novel europium complexes of 2'-hydroxyacetophenone and 4,6-diacetylresorcinol

Novel europium (III) complexes of the formulae Eu(OHAP)(3).2H2O, Eu(OHAP)(3)Phen, Eu2(DAR)(3).4H2O and Eu2(DAR)(3)Phen2 (HOHAP=2'-hydroxyacetophenone, H2DAR=4,6-diacetylresorcinol, Phen=1,10-phenanthroline) have been designed and synthesized in this paper. These complexes were characterized by elemental analysis, FT-IR, and UV-vis. Based on these observations, the ligands are coordinated to Eu(III) via the acetyl and phenolic oxygens, and H2DAR is concluded to be bis-bidentate donor. Photoluminescence studies showed that the several complexes emitted red luminescence. Thermo-gravimetric analysis showed that the complexes possess good thermal stability. Also, it was found that Phen as a synergic ligand, coordinated to Eu(III) in a composite system like 2'-hydroxyacetophenone and 4,6-diacetylresorcinol, could enhance the complexes luminescence intensity, quantum yield and lifetime.     

稀土螯合物发光体LB膜的研究(I)

稀土有机配合物的发光研究近年来取得了可喜的近展.铕(Ⅲ)、铽(Ⅲ)、钐(Ⅲ)与β-二酮(β-dik),三正辛基氧化膦(TOPO)所形成的螯合物,以及它们的硝酸盐与邻菲咯啉(Phen)所形成的螯合物都是高光效的发光体,有广阔的应用前景,在某些方面已获得应用.如能把这些具有发光功能的稀土螯合物组装成有序的分子组合体,则很可能在分子光学技术,光电子技术等领域发挥重要作用.如何组装?本文用LB 膜技术,通过交替成膜或混     

Structure and dynamics of binary and ternary lanthanide(III) and actinide(III) tris[4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedione] (TTA) complexes. Part 2, the structure and dynamics of binary and ternary complexes in the Y(III)/Eu(III)-TTA-tributylphosphate (TBP) system in chloroform as studied by NMR spectroscopy

The stoichiometric reaction mechanisms, rate constants and activation parameters for inter- and intramolecular ligand exchange reactions in the binary Y/Eu(TTA)(3)(OH(2))(2)-HTTA and the ternary Y/Eu(TTA)(3)(OH(2))(2)-TBP systems have been studied in chloroform using (1)H and (31)P NMR methods. Most complexes contain coordinated water that is in very fast exchange with water in the chloroform solvent. The exchange reactions involving TTA/HTTA and TBP are also fast, but can be studied at lower temperature. The rate constant and activation parameters for the intramolecular exchange between two structure isomers in Y(TTA)(3)(OH(2))(2) and Y(TTA)(3)(TBP)(OH(2)) were determined from the line-broadening of the methine protons in coordinated TTA. The rate equations for the intermolecular exchange between coordinated TTA and free HTTA in both complexes are consistent with a two-step mechanism where the first step is a fast complex formation of HTTA, followed by a rate determining step involving proton transfer from coordinated HTTA to TTA. The rate constants for both the inter- and intramolecular exchange reactions are significantly smaller in the TBP system. The same is true for the activation parameters in the Y(TTA)(3)(OH(2))(2)-HTTA and the ternary Y/Eu(TTA)(3)(TBP)(OH(2))-HTTA systems, which are ΔH(≠) = 71.8 ± 2.8 kJ mol(-1), ΔS(≠) = 62.4 ± 10.3 J mol(-1) K(-1) and ΔH(≠) = 38.8 ± 0.6 kJ mol(-1), ΔS(≠) = -93.0 ± 3.3 J mol(-1) K(-1), respectively. The large difference in the activation parameters does not seem to be related to a difference in mechanism as judged by the rate equation; this point will be discussed in a following communication. The rate and mechanism for the exchange between free and coordinated TBP follows a two-step mechanism, involving the formation of Y(TTA)(3)(TBP)(2).     

Synthesis,characterization, photophysical and oxygen-sensing properties of a copper(I) complex

In this paper, we report the synthesis, crystal structure, photophysical properties, and electronic nature of a phosphorescent Cu(I) complex of [Cu(TBT)(POP)]BF₄, where TBT and POP stand for 4,5,9,14-tetraaza-benzo[b]triphenylene and bis(2-(diphenylphosphanyl)phenyl) ether, respectively. [Cu(TBT)(POP)]BF₄ renders a red phosphorescence peaking at 622 nm, with a long excited-state lifetime of 13.2 μs. Density functional calculation reveals that the emission comes from a triplet metal-to-ligand-charge-transfer excited state. We electrospun composite nanofibers of [Cu(TBT)(POP)]BF₄ and polystyrene, hoping to explore the possibility of replacing precious-metal-based oxygen sensors with cheap Cu-based ones. The finally obtained samples with average diameter of ~700 nm exhibit a maximum sensitivity of 5.8 toward molecular oxygen with short response/recovery time (5/13 s) due to the large surface-area-to-volume ratio of nanofibrous membranes. No photobleaching is detected in these samples. All these results suggest that phosphorescent Cu(I) complexes doped nanofibrous membranes are promising candidates for low-cost and quick-response oxygen-sensing materials.     

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(Ⅲ) complex-doped PMMA having fast radiation rate and high emission quantum efficiency

Three Eu(Ⅲ) ternary complexes,Eu(hfa-H) 3(Phen),Eu(hfa-H) 3(Bipy) and Eu(hfa-H) 3(Bath)(hfa = hexafluoroacetylacetonate,Phen = 1,10-phenanthroline,Bipy = 2,2 0-bipyridine,Bath = bathophenanthroline),were synthesized.Their luminescent properties were studied by incorporating deuterated Eu(Ⅲ) complexes in a poly(methylmethacrylate)(PMMA) matrix,and the results indicated that luminescent PMMA including Eu(hfa-D) 3(Bath) showed promising results for applications to novel organic Eu(Ⅲ) devices,such as the high-power laser materials.Additionally,all the three Eu(Ⅲ) complexes exhibited good thermostabilization.     

稀土-二苯甲酰甲烷、邻菲咯啉固态配合物及其掺杂硅胶共发光效应的光声光谱研究

合成了Eu(Dbm)₃·Phen同核和Eu_0.8Ln_0.2(Dbm)₃·Phen(Ln:Er³⁺,Y³⁺)异核固体配合物微晶粉末及其掺杂的SiO2凝胶样品,在300～800nm范围内测定了其光声光谱.结果表明,配合物Eu_0.8Er_0.2(Dbm)₃·Phen,Eu(Dbm)₃·Phen和Eu_0.8Y_0.2(Dbm)₃·Phen配体吸收处的光声强度依次减弱;而Eu_0.8Y_0.2(Dbm)₃·Phen和Eu(Dbm)₃·Phen配合物掺杂的凝胶则情况相反.研究发现,光声强度与稀土配合物分子中能量传递过程相关,Er³⁺,Y³⁺离子的引入改变了三元配合物的弛豫过程,且配合物在粉末状态和凝胶状态的弛豫历程不尽相同.结合荧光光谱,从无辐射跃迁和辐射跃迁的角度分析了标题化合物在两种不同固体状态下的发光性质.     

Application of chelate phosphine oxide ligand in EuIII complex with mezzo triplet energy level, highly efficient photoluminescent, and electroluminescent performances

The chelate phosphine oxide ligand bis(2-(diphenylphosphino)phenyl) ether oxide (DPEPO) was used as a unit neutral ligand to prepare the complex Eu(TTA)(3)(DPEPO) 1 (TTA = 2-thenoyltrifluoroacetonate). Compound 1 has a photoluminescence (PL) quantum yield of 55.3%, which is more than the twice of the PL quantum yield of Eu(TTA)(3)(TPPO)(2) (TPPO = triphenylphosphine oxide). Investigation indicated that DPEPO in 1 has the mezzo first triplet excited energy level (T(1)) between the first singlet excited energy level (S(1)) and T(1) of TTA, which may support one more additional energy transfer routines from the T(1) energy level of DPEPO to that of TTA, and consequently results in the improvement of energy transfer in the Eu(III) complex. DPEPO forms a complex with a more rigid and compact structure that can improve energy transfer between ligands and the center Eu(III) ion, support the higher saturation level by the coordinating ability of the oxygen atom in the ether moiety, and consequently enhance the PL intensity and efficiency of the corresponding Eu(III) complex. The multilayered electroluminescent (EL) device of 1 used as the red dopant exhibited an impressive brightness of 632 cd m(-2) at 25 V. The device had the excellent voltage-independent spectral stability with an emission peak at 615 nm. To the best of our knowledge, this luminescence is the brightest emission among Eu complexes with phosphine oxide ligands. The maximum external quantum yield (eta(ext)) of 2.89% and the maximum current and power efficiency of 4.58 cd A(-1) and 2.05 lm W(-1) were achieved at a low turn-on voltage of 7 V and current density of 0.021 mA cm(-2). These properties demonstrate that the chelate phosphine oxides ligand DPEPO can not only be favorable to form the rigid and compact complex structure and increase the efficiency of devices, but also reduce the ability of the formation of exciplex. DPEPO shows much better performance compared with the ordinary phosphine oxide ligand triphenylphosphine oxide.     

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.