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1.
In this article, dibenzoylmethane (DBM) was first grafted with the coupling reagent 3-(triethoxysilyl)-propyl isocyanate (TESPIC) to form precursor DBM–Si, and ZnO quantum dot was modified with 3-mercaptopropyltrimethoxysilane (MPS) to form SiO2/ZnO nanocomposite particle. Then the precursor DBM–Si and the terminal ligand 1,10-phenthroline (phen) were coordinated to Eu3+ion to obtain ternary hybrid material phen–Eu–DBM–SiO2/ZnO after hydrolysis and copolycondensation between the tetraethoxysilane (TEOS), water molecules and the SiO2/ZnO network via the sol–gel process. In addition, for comparison, the binary hybrid material with SiO2/ZnO network and ternary hybrid material with pure Si–O network were also synthesized, denoted as Eu–DBM–SiO2/ZnO and phen–Eu–DBM–Si, respectively. The results reveal that hybrid material with SiO2/ZnO network phen–Eu–DBM–SiO2/ZnO exhibits the stronger red light, the longer lifetimes and higher quantum efficiency than hybrid material with pure Si–O network phen–Eu–DBM–Si, suggesting that SiO2/ZnO is a favorable host matrix for the luminescence of rare earth complexes.  相似文献   

2.
1,3‐Diphenyl‐1,3‐propanepione (DBM)‐functionalized SBA‐15 and SBA‐16 mesoporous hybrid materials (DBM‐SBA‐15 and DBM‐SBA‐16) are synthesized by co‐condensation of modified 1,3‐diphenyl‐1,3‐propanepione (DBM‐Si) and tetraethoxysilane (TEOS) in the presence of Pluronic P123 and Pluronic F127 as a template, respectively. The as‐synthesized mesoporous hybrid material DBM‐SBA‐15 and DBM‐SBA‐16 are used as the first precursor, and the second precursor poly(methylacrylic acid) (PMAA) is synthesized through the addition polymerization reaction of the monomer methacrylic acid. These precursors then coordinate to lanthanide ions simultaneously, and the final mesoporous polymeric hybrid materials Ln(DBM‐SBA‐15)3PMAA and Ln(DBM‐SBA‐16)3PMAA (Ln=Eu, Tb) are obtained by a sol‐gel process. For comparison, binary lanthanide SBA‐15 and SBA‐16 mesoporous hybrid materials (denoted as Ln(DBM‐SBA‐15)3 and Ln(DBM‐SBA‐16)3) are also synthesized. The luminescence properties of these resulting materials are characterized in detail, and the results reveal that ternary lanthanide mesoporous polymeric hybrid materials present stronger luminescence intensities, longer lifetimes, and higher luminescence quantum efficiencies than the binary lanthanide mesoporous hybrid materials. This indicates that the introduction of the organic polymer chain is a benefit for the luminescence properties of the overall hybrid system. In addition, the SBA‐15 mesoporous hybrids show an overall increase in luminescence lifetime and quantum efficiency compared with SBA‐16 mesoporous hybrids, indicating that SBA‐15 is a better host material for the lanthanide complex than mesoporous silica SBA‐16.  相似文献   

3.
Novel mesoporous SBA-16 type of hybrids TTA-S16 and DBM-S16 were synthesized by co-condensation of modified β-diketone (TTA-Si and DBM-Si, DBM=1,3-diphenyl-1,3- propanepione, TTA=2-thenoyltrifluoroacetone) and tetraethoxysilane (TEOS) in the presence of Pluronic F127 as template, which were confirmed by FTIR, XRD, 29Si CP-MAS NMR, and N2 adsorption measurements. Novel organic-inorganic mesoporous luminescent hybrid containing RE3+ (Eu3+, Tb3+) complexes covalently attached to the functionalized ordered mesoporous SBA-16 (TTA-S16 and DBM-S16), which were designated as bpy-RE-TTA-S16 and bpy-RE-DBM-S16, were obtained by sol-gel process. The luminescence properties of these resulting materials were characterized in detail, and the results reveal that mesoporous hybrid material bpy-Eu-TTA-S16 present stronger luminescent intensities, longer lifetimes, and higher luminescent quantum efficiencies than the corresponding DBM-containing materials bpy-Eu-DBM-S16, while bpy-Tb-DBM-S16 exhibit the stronger characteristic emission of Tb3+ and longer lifetime than the corresponding TTA-containing materials bpy-Tb-TTA-S16.  相似文献   

4.
赵春霞  陈文  刘琦  田高 《无机化学学报》2006,22(9):1600-1604
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。  相似文献   

5.
The crystal structure of a ternary Tm(DBM)3phen complex (DBM=dibenzoylmethane; phen=1, 10-phenanthroline) and the synthesis of hybrid mesoporous material in which the complex covalently bonded to mesoporous MCM-41 are reported. Crystal data: Tm(DBM)3phen C59H47N2O7Tm, monoclinic, P21/c, a=19.3216(12) Å, b=10.6691(7) Å, c=23.0165(15) Å, α=90°, β=91.6330(10)°, γ=90°, V=4742.8(5) Å3, Z=4. The properties of the Tm(DBM)3phen complex and the corresponding hybrid mesoporous material [Tm(DBM)3phen-MCM-41] have been studied. The results reveal that the Tm(DBM)3phen complex is successfully covalently bonded to MCM-41. Both Tm(DBM)3phen complex and Tm(DBM)3phen-MCM-41 display typical near-infrared (NIR) luminescence upon excitation at the maximum absorption of the ligands, which contributes to the efficient energy transfer from the ligands to the Tm3+ ion, an antenna effect. The full width at half maximum (FWHM) centered at 1474 nm in the emission spectrum of Tm(DBM)3phen-MCM-41 is 110 nm, which is the potential candidate of broadening amplification band from C band (1530-1560 nm) to S+ band (1450-1480 nm) in optical area.  相似文献   

6.
Two series of Eu3+-doped homologous-SBA-15 materials (abbreviated as MPTMS-SBA-15: Eu3+ and CTMS-SBA-15: Eu3+) have been synthesized by a hydrolysis-controlled technology, in which two novel silane crosslinking reagents (3-(methacryloyloxy) propyltrimethoxysilane (MPTMS) and 3-(chloropropyl) trimethoxysilane (CTMS)) are used as silicate precursor instead of traditional tetraethoxysilane (TEOS). It can be found that the different silicate precursors with different functional groups have influence on the physical properties of the corresponding homologous materials. In comparison to the pure SBA-15, the BET surface area and pore size of the modified mesoporous materials have been changed. Finally, the characteristic luminescence is observed for the 5D0 → 7FJ (J = 0, 1, 2) transition of Eu3+ ion, suggesting that these kind of homologous-SBA-15 materials are potential host for the luminescence of Eu3+, whose excitation energy can be quenched by Eu3+ to some extent.  相似文献   

7.
Novel organic-inorganic mesoporous hybrid materials were synthesized by linking lanthanide (Tb3+, Eu3+) complexes to the mesoporous MCM-41 through the modified meta-methylbenzoic acid (MMBA-Si) using co-condensation method in the presence of the cetyltrimethylammonium bromide (CTAB) surfactant as template. The luminescence properties of these resulting materials (denoted as Ln-MMBA-MCM-41, Ln=Tb, Eu) were characterized in detail, and the results reveal that luminescent mesoporous materials have high surface area, uniformity in the ordered mesoporous structure. Moreover, the mesoporous material covalently bonded Tb3+ complex (Tb-MMBA-MCM-41) exhibits the stronger characteristic emission of Tb3+ and longer lifetime than Eu-MMBA-MCM-41 due to the triplet state energy of organic legend MMBA-Si matches with the emissive energy level of Tb3+ very well.  相似文献   

8.
Hybrid materials doped with novel europium complexes were synthesized using PMMA‐co‐Sn12Clusters (copolymers from oxohydroxo‐organotin dimethacrylate and methylmethacrylate) as the matrix material. Two types of hybrid materials were obtained: the physically doped product, PMMA‐co‐Sn12Cluster/Eu(TTA)3phen, and the grafted product, PMMA‐co‐Sn12Cluster‐co‐[EuAA(TTA)2phen] (TTA=2‐thenoyltrifluoroacetone, phen=phenanthroline and AA=acrylic acid). The hybrid materials exhibited characteristic luminescence of the Eu3+ ions, and also showed relative especial optical properties compared with samples just using PMMA as the matrix material. The PMMA‐co‐Sn12Cluster matrix exhibited a high physical doping quantity of [Eu(TTA)3phen], which can be attributed to the special structure of this kind of hybrid material. GPC (gel‐permeation chromatography), TGA (thermogravimetric analysis), SEM, 1H NMR, ICP (inductively coupled plasma), 119Sn NMR, FTIR, and diffuse reflectance techniques were employed to characterize the structures and properties of these hybrid materials.  相似文献   

9.
Nanoparticles (NPs) from diketonates of Al3+, Sc3+, In3+ and Ln3+ doped with dye molecules are synthesized. The appearance of sensitized fluorescence (cofluorescence) of dye molecules due to energy transfer from the ensemble of complexes forming NPs is revealed in aqueous solutions of these NPs. It is shown that the dye cofluorescence in NPs from Eu complexes occurs as a result of two distinct processes of energy transfer (ET) to dye molecules: from singlet levels of ligands and from Eu3+ ions. It is found that the efficiency of ET from Eu3+ ions to dyes in NPs from Eu(DBM)3phen is one order of magnitude higher than the efficiency of ET from S1-levels of ligands to dyes in NPs from Al complexes with the same ligands. It is shown that the excitation of dye molecules through ligands of NPs results in the enhancement of the intensity of their fluorescence by a factor of 1.5–2 orders of magnitude compared to the excitation of their own first band of absorption.  相似文献   

10.
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.  相似文献   

11.
Lanthanide upconversion luminescence in nanoparticles has prompted continuous breakthroughs in information storage, temperature sensing, and biomedical applications, among others. Achieving upconversion luminescence at the molecular scale is still a critical challenge in modern chemistry. In this work, we explored the upconversion luminescence of solution dispersions of co-crystals composed of discrete mononuclear Yb(DBM)3Bpy and Eu(DBM)3Bpy complexes (DBM: dibenzoylmethane, Bpy: 2,2′-bipyridine). The 613 nm emission of Eu3+ was observed under excitation of Yb3+ at 980 nm. From the series of molecular assemblies studied, the most intense luminescence was obtained for a 1 : 1 molar ratio of Yb3+ : Eu3+, resulting in a high quantum yield of 0.67 % at 2.1 W cm−2. The structure and energy transfer mechanism of the assemblies were fully characterized. This is the first example of an Eu3+-based upconverting system composed of two discrete mononuclear lanthanide complexes present as co-crystals in non-deuterated solution.  相似文献   

12.
The effect of the electronic excitation of the -diketonate Eu(fod)3 (fod is 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyloctanedione-3,5) on complexation with 1,10-phenanthroline (phen) in benzene solutions was studied. The excitation of the ff transitions of Eu3+ increased the stability of the Eu(fod)3 · phen complex, thus providing direct evidence for the involvement of the 4f shell of Eu3+ in chemical bonding. The thermodynamic parameters of complexation were determined. The temperature quenching of Eu(fod)3 · phen luminescence was studied.  相似文献   

13.
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.  相似文献   

14.
使用二苯甲酰甲烷-二苯菲罗啉-铕(Eu(DBM)3BPhen)作为电子给体和[6,6]-苯基-C61-丁酸酸甲酯([60]PCBM)作为电子受体制备了一种新型的有机光盲型紫外探测器.在光强为2.1 mW cm-2且波长为360 nm的紫外光照射下,获得了26 mA W-1的响应度和9.1%的外量子效率,这是由于Eu(DBM)3BPhen的强紫外光吸收能力和长达300μs的激子寿命使得给受体界面处具有较高的激子解离率.在把[60]PCBM掺入Eu(DBM)3BPhen后,观察到了明显的光致发光猝灭和光电导现象.由于材料较低的载流子迁移率和受陷激子的缓慢释放,在紫外光照射关闭后,观察到了较强的持续光电导现象.  相似文献   

15.
Two europium trifluoroacetate complexes, Eu(CF3COO)3·phen ( 1 ) and Eu(CF3COO)3·bpy ( 2 ) (where phen=1,10‐phenanthroline, bpy=2,2′‐bipyridine), were synthesized and characterized by elemental analysis, Fourier transform infrared spectroscopy (FT‐IR), photoluminescence (PL) spectroscopy and thermogravimetric analysis (TA). Single‐crystal X‐ray structure has been determined for the complex [Eu2(CF3COO)6·(phen)3·(H2O)2]·EtOH. The crystal structure of [Eu2(CF3COO)6·(phen)3·(H2O)2]·EtOH shows that two different coordination styles with europium ions coexist in the same crystal and have entirely different coordination geometries and numbers. This crystal can be considered as an 1:1 adduct of [Eu(CF3COO)3·(Phen)2·H2O]·EtOH (9‐coordination part) and Eu(CF3COO)3·phen·H2O (8‐coordination part). The excitation spectra of the two complexes demonstrate that the energy collected by "antenna ligands" is transferred to Eu3+ ions efficiently. The room‐temperature PL spectra of the complexes are composed of the typical Eu3+ ions red emission, due to transitions between 5D07FJ(J=0→4). The lifetimes of 5D0 of Eu3+ in the complexes were examined using time‐resolved spectroscopic analysis, and the lifetime values of Eu(CF3COO)3·phen and Eu(CF3COO)3·bpy were fitting with bi‐exponential (2987 and 353 µs) and monoexponential (3191 µs) curves, respectively. In order to elucidate the energy transfer process of the europium complexes, the energy levels of the relevant electronic states had been estimated. The thermal analyses indicate that they are all quite stable to heat.  相似文献   

16.
Eu2+-doped inorganic-organic hybrid materials, which are potentially suitable for a tunable laser in the near ultra violet and blue region, were prepared through the photoreduction of Eu3+ ions in the materials under the irradiation of the fourth harmonic wave light (266 nm) of the Nd:YAG laser. The hybrid materials doped with Eu3+ ions were prepared from Si(OCH3)4, CH3Si(OCH3)3, EuCl3 and chloropropyltrimethoxysilane (CPTM). After the prehydrolized silica sol was added to the Eu3+-containing solution, Eu3+-doped transparent inorganic-organic hybrid material was obtained by drying at 50°C. The emission peak around 450–475 nm due to the charge transfer transition (5d-4f) of Eu2+ ions increased with the laser irradiation time. Eu3+ ions were effectively photoreduced to Eu2+ ions in pore-free materials prepared at high CPTM to Eu3+ ratios. Eu2+ ions were generated by the photodecomposition of the bond between Eu3+ and Cl (Cl or Cl(CH2)3 in CPTM).  相似文献   

17.
Adducts of lanthanide β-diketonates of the general formula LnL3(TPTZ) were synthesized and structurally characterized by single crystal X-ray diffraction [Ln = Eu3+, Tb3+, Er3+; L is the conjugate base of dibenzoylmethane (DBM), 1-benzoylacetone (BA), thenoyltrifluoroacetone (TTA), or 4,4,4-trifluoro-1-phenyl-1,3-butanedione (BTFA); TPTZ = 2,4,6-tri(2-pyridyl)-1,3,5-triazine, a rigid Lewis base with a large π system]. The lanthanide ion in each of these complexes is nonacoordinate with six β-diketonate oxygen atoms and three TPTZ nitrogen atoms, forming a coordination polyhedron best describable as a monocapped square antiprism. Characteristic red, green, and near infrared luminescence was observed for the Eu3+, Tb3+, and Er3+ complexes, respectively. All complexes showed significantly enhanced luminescence quantum yields when compared with the corresponding aqua analogues, with one of the Eu3+ complexes displaying a quantum yield of 69.7% in chloroform.  相似文献   

18.
Ligand N2,N6‐bis(2‐hydroxyethyl)pyridine‐2,6‐dicarboxamide (L=BHPC) was synthesized and used to construct lanthanide‐based mesoporous material Eu‐L‐MCM‐41. In the structure of resulting Eu‐L‐MCM‐41, Eu3+ was chelated by BHPC, and the Eu‐L complexes were anchored into the forming MCM‐41 host by the reaction between the hydroxyl group and active Si‐OH. The mesoporous material Eu‐L‐MCM‐41 was characterized by UV, IR, small‐angle X‐ray diffraction (SAXRD) patterns, nitrogen adsorption/desorption isotherms, TGA and fluorescence spectra. The results indicate that ligand and Eu3+ have been introduced into the MCM‐41 host, and Eu‐L‐MCM‐41 exhibits characteristic luminescence of Eu3+.  相似文献   

19.
Two lanthanide complexes with 2-fluorobenzoate (2-FBA) and 1,10-phenanthroline (phen) were synthesized and characterized by X-ray diffraction. The structure of each complex contains two non-equivalent binuclear molecules, [Ln(2-FBA)3?·?phen?·?CH3CH2OH]2 and [Ln(2-FBA)3?·?phen]2 (Ln?=?Eu (1) and Sm (2)). In [Ln(2-FBA)3?·?phen?·?CH3CH2OH]2, the Ln3+ is surrounded by eight atoms, five O atoms from five 2-FBA groups, one O atom from ethanol and two N atoms from phen ligand; 2-FBA groups coordinate Ln3+ with monodentate and bridging coordination modes. The polyhedron around Ln3+ is a distorted square-antiprism. In [Ln(2-FBA)3?·?phen]2, the Ln3+ is coordinated by nine atoms, seven O atoms from five 2-FBA groups and two N atoms of phen ligand; 2-FBA groups coordinate Ln3+ ion with chelating, bridging and chelating-bridging three coordination modes. The polyhedron around Ln3+ ion is a distorted, monocapped square-antiprism. The europium complex exhibits strong red fluorescence from 5D0?→?7F j ( j?=?1–4) transition emission of Eu3+.  相似文献   

20.
Hydrates of Eu(III) and Tb(III) salts with anions (L) 4-CF3C6F4COO? and 4-(CF3)2CFC6F4COO?, and also mixed-ligand complexes Ln(phen)(L)3 were obtained. The compounds show red and green photoluminescence characteristic of Eu3+ and Tb3+ ions, respectively, in the visible region of spectrum. The intensity of the photoluminescence of the complexes containing 1,10-phenanthroline is much higher than that of compounds containing water. It is connected with sensitizing properties of phen in relation to Eu3+ and Tb3+ ions.  相似文献   

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