Ho3+对二苯亚砜高氯酸铕配合物发光的影响

合成了高氯酸铕二苯亚砜和不同物质量比的高氯酸(Ⅲ)、钬(Ⅲ)二苯亚砜异核配合物(EuxHo1-x)(DPSO)7(ClO4)3.测定了配合物的组成、IR、粉晶荧光激发和发射光谱.荧光光谱表明虽然Ho3+的发射几率较高的5S2激发态能级高于Eu3+,但并未对Eu3+的发光产生敏化作用,相反当掺入0.002mol的Ho3+时即对Eu3+的发光产生猝灭作用.另外从Eu3+的荧光光谱知5D0→7F2的电偶极跃迁强度大大高于5D0→7F1的磁偶极跃迁,这表明铕(Ⅲ)在配合物晶体中处于非对称中心的位置.     

对甲苯基苯乙烯基亚砜稀土高氯酸盐体系中Tm3+→Eu3+的荧光增强效应

合成并表征了六种不同掺杂比例稀土高氯酸铕掺铥与对甲苯基苯乙烯基亚砜的固态配合物.经元素分析确定了配合物的组成为:(EuxTm1-x) (ClO4)3*L7(x=1.000,0.999,0.995,0.990,0.950,0.900; L= C6H5CH=CHSOC6H4CH3).配合物的红外光谱表明,配体通过亚砜基氧原子与稀土离子配位,烯键未参与配位.在丙酮溶液中测定的摩尔电导率表明,配合物为1∶2型电解质,三个 ClO4-无机抗衡阴离子,其中一个在内界,两个在外界.配合物的荧光发射光谱中出现了比磁偶极跃迁(5D0→7F1)强的电偶极跃迁(5D0→7F2),表明配合物不存在反演中心.掺杂配合物的荧光光谱表明,将千分之一的铥掺入后,铕离子的发光增强增加到111%.     

2,4,6-三吡啶基三嗪稀土配合物的红外光谱和荧光性能

首次合成了以 2,4,6-三吡啶基三嗪(TPTZ)为配体,以钐、铕、铽和镝为中心的稀土配合物.经元素分析、红外光谱和摩尔电导率测试表明,配合物的组成为RE(TPTZ)2·(ClO4)3(RE=Sm, Eu,Tb, Dy),稀土离子与2个TPTZ的6个氮原子和1个高氯酸根离子配位,另2个高氯酸根离子在外界未参与配位. 荧光光谱的测试表明,Tb3 配合物具有较强的特征荧光发射,位于490.4nm的5D4→7F6跃迁很强,接近5D4→7F5跃迁.     

铕-苯甲酸-1,10-菲咯啉的合成及谱学性质

合成了稀土元素铕( )-苯甲酸-1,10-菲咯啉的三元配合物。通过元素分析和红外光谱确定了配合物的组成为EuL3phen(L∶苯甲酸根,phen∶1,10-菲咯啉)。通过发射光谱和激发光谱的测试表明,三元配合物在579、591、614、649、690nm处产生发射峰,分别归属于Eu3+的5D0→7F0、5D0→7F1、5D0→7F2、5D0→7F3、5D0→7F4跃迁。从发射光谱的峰强和激发光谱在200nm～380nm范围内产生宽而强的吸收峰可以得出第二配体phen的加入能显著增加Eu3+的发光强度,由此说明phen的加入更有利于配体吸收能量,也有利于配体更有效地向Eu3+传递能量。另外,对三元配合物的远红外光谱和拉曼光谱进行了分析。     

SiO2@ZnWO4∶Eu3+红色荧光粉的制备及其发光性质研究

以正硅酸乙酯为硅源,用水热法制备了SiO2@ZnWO4∶Eu3+荧光粉,对样品分别进行了X射线衍射(XRD)、透射电镜(TEM)、荧光光谱(PL)等表征。XRD结果表明,当水热反应温度为180℃,反应时间12小时,可以得到ZnWO4的纯相。TEM和EDS结果表明,样品中含有Si、Eu、O、Zn、W元素。荧光光谱结果表明,SiO2@Zn-WO4∶Eu3+荧光粉能够被393 nm的紫外光激发,在615 nm处发出红色荧光,且SiO2@ZnWO4∶Eu3+荧光粉的发射光谱中电偶极跃迁5D0→7F2强度大于磁偶极跃迁5D0→7F1的强度,表明Eu3+在其中处于没有对称中心的格位。     

BaM_2ZnO_5∶Eu~(3+)(M=La,Gd)荧光粉的合成及其光谱研究

为了探索Eu3+在晶格位置中占据不同对称中心时的发光性质,采用高温固相法制备了BaM2ZnO5∶Eu3+(M=La,Gd)系列红色荧光粉,分别用X射线衍射(XRD)、扫描电镜(SEM)、荧光光谱(PL)对其晶体结构、形貌和发光性质进行了表征。结果表明,经1000℃烧结后可得到BaM2ZnO5(M=La,Gd)纯相,荧光粉的颗粒大小分布较均匀,粒径大约为3μm~5μm;BaM2ZnO5∶Eu3+(M=La,Gd)荧光粉可以被395 nm的近紫外光有效激发,BaLa2ZnO5∶Eu3+在595 nm处的发射峰为最强峰,对应于Eu3+的5D0→7F1(595 nm)磁偶极跃迁。Ba Gd2ZnO5∶Eu3+在627 nm处的发射峰为最强峰,对应于Eu3+的5D0→7F2(615 nm,627 nm)电偶极跃迁。     

Eu(Ⅲ)-β-NPA-HTTA二元、三元配合物的合成和光谱研究

为了获得高光效、高稳定性能的发光材料,探讨β-萘甲酸(β-NPA)化合物在发光材料方面的应用,合成了Eu(Ⅲ)与β-NPA及2-噻吩甲酰三氟丙酮(HTTA)形成的二元、三元荧光配合物。对所合成的配合物利用元素分析、紫外可见光谱、红外光谱、荧光光谱等手段进行了表征。对稀土配合物的结构与发光性能之间的关系进行了探讨。表征结构表明,两个配合物的组成分别为Eu(β-NPA)_3·3H_2O和Eu(β-NPA)(TTA)_2·2H_2O;紫外光谱研究表明,β-NPA与铕离子配位后整个体系的共轭程度增大,使得配合物的紫外吸收能力增强;荧光光谱研究显示,与铕离子反应后的配合物的配体β-NPA、2-HTTA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(β-NPA)_3·3H_2O,Eu(β-NPA)(TTA)_2·2H_2O均以~5D_0→~7F_2跃迁的荧光发射最强。得到了两种高效的红色荧光配合物Eu(β-NPA)_3·3H_2O,Eu(β-NPA)(TTA)_2·2H_2O,它们可望成为制备鲜艳红色发光材料的侯选。     

Eu3+掺杂Sr2CeO4荧光体的制备、发光性能及能量传递

采用柠檬酸-凝胶法成功地制备了Eu3+掺杂的Sr2CeO4荧光体.用X射线粉末衍射、拉曼光谱、紫外可见吸收光谱和荧光光谱等分析手段研究了荧光体的结构、光致发光性能及能量传递.结果表明,Sr2CeO4∶ Eu荧光体的激发光谱由两部分组成一个宽的激发带和属于Eu3+的f - f跃迁的锐线谱(峰位是395nm、466nm、532nm),它的发射光谱中除了出现常见的发射峰如585nm(5D0→7F1) 、616nm(5D0→7F2)、655nm(5D0→7F3)和704nm(5D0→7F4)外,还包含有来自较高能级激发态5D1的跃迁的发射,即509nm(5D1→7F0)、534nm(5D1→7F1)、554nm(5D1→7F2).这些发射峰在其它基质材料中难以观察到.发射主峰位于616nm附近,没有出现5D0→7F0的跃迁发射,这表明Eu3+在Sr2CeO4基质中处于无反演中心或偏离反演中心的格位上.Sr2CeO4∶Eu荧光体中存在着从基质Sr2CeO4到Eu3+的能量传递.     

稀土铕,铽β-二酮配合物的合成与发光性能

采用Claisen缩合反应合成了一种新型的β-二酮化合物1-(4-溴苯)-3-苯基丙烷-1,3-二酮(L),并以其为第一配体,邻菲罗啉(phen)为第二配体,合成出新型稀土铕,铽二元及三元配合物。通过元素分析、红外光谱、紫外光谱、荧光光谱对合成的配体及配合物进行了表征。元素分析确定了配合物的组成。红外光谱的分析表明第一配体L中的氧原子以及第二配体phen中的氮原子与稀土离子进行了配位。紫外光谱表明第一配体L为能量的给体,第二配体phen起协同作用。通过荧光光谱研究了配合物的发光性质,结果显示三元配合物的发光强度大于二元配合物,三元配合物Eu(L)3phen表现出Eu3+的特征发射,在593,615,653,701 nm处的发射峰分别归属于Eu3+的5D0→7Fj(j=1,2,3,4)能级间的跃迁,并且以位于615 nm处的5D0→7F2电子跃迁所发出的荧光强度最大;而铽配合物中并没有出现Tb3+的特征发射。进一步的研究表明,这是由于配体L的最低三重态能级较适合Eu3+的发射能级,配体L吸收的能量可以有效的通过Antenna效应传递给稀土中心离子,使得三元配合物Eu(L)3phen的发光强度较大。     

铕与三种不同结构羧酸配合物的低温固相合成及发光性能研究

以共轭体系大小不同、配位基团与共轭体系的距离不同的三种羧酸:1-萘甲酸、苯甲酸、苯乙酸和氯化稀土为原料,采用低温固相反应合成了三种羧酸铕配合物.经元素分析、稀土络合滴定、摩尔电导确定了配合物的组成为:Eu(L1)3,Eu(L2)3·1.5H2O,Eu(L3)3·1.5H2O(L1=C10H7COO-,L2=C6H5COO-,L3=C6H5CH2COO-).测定了配体及配合物的的IR谱、1HNMR谱及配体的磷光光谱和铕配合物荧光激发和发射光谱.根据磷光发射光谱数据计算了配体的三重态能级值.三个配合物的荧光发射主峰5D0→7F2强度按萘甲酸铕苯甲酸铕>苯乙酸铕的顺序变化,由此可见配体的结构不同对铕离子的发光将产生很大的影响.     

Synthesis and Fluorescence Property of Eu^3 ＋ , Tb^3＋ Perchlorate Complexes with Diphenyl Sulfoxide and 1,10-Phenanthroline

Eu3 ,Tb3 canemitfluorescenceinconjugatedsystemcontainingorganicligand[1,2 ] ,forexample ,1 ,1 0 phenanthroline ,becauseithasbettercoordina tionabilityandbiggerconjugationsystem ,soitcantransmitenergyeffectivelytoEu3 ,Tb3 ,leadingtofluorescenceemission ,andthestabilityisveryhigh ,butsolubilityisverypoor .Inaddition ,diphenylsul foxidehasbettercoordinationabilityandbiggerconju gationsystem ,too .Soitcanalsotransmitenergyef fectivelytoEu3 ,Tb3 ,resutlinginfluorescencee mission ,andsolubi…     

Enhancement of red to orange emission ratio of YPO4：Eu3＋,Ce3＋ and its dependence on Ce3＋ concentration

Eu3+ and Ce3+ co-doped YPO4 microspheres were synthesized by hydrothermal method without template. The emission spectra showed that the red emission centered at 618nm could be readily increased relatively to the orange emission centered at 590nm by controlling the doping concentration of Ce3+ ion. The investigation based on excitation spectra and decay curves demonstrated that the doped Ce3+ ions took two efficient energy transfers to Eu3+ ions and affected the lifetime of the emission states of Eu3+ ions so that the emission spectra of Eu3+ ion were accordingly tuned with the Ce3+ content increasing. This controllable red (5D0→7F2) to orange ( 5D0→7F1) emission ratio of YPO4:Eu3+,Ce3+ made it very promising for encoded anti-fake labels and bio-labels.     

Study on Fluorescence Properties of Eu（ Ⅲ ） Cryptates

The mononuelear eryptate [Eu(H3L^F) (NO3) (H2O) ] (NO3)2 and the heterodinuclear eryptate [EuZnL^F(DMF) ] (C1O4)2 were synthesized and characterized. The triplet-state energy of the cryptand (H3Lr) was studied by phosphorescence spectrum. The fluorescent properties of Eu(m) cryptates in MeOH solution show that the cryptand (H3L^F) can sensitize the Eu(Ⅲ) ion to luminescence and the introduction of the Zn(Ⅱ ) ion into the mononuclear Eu( Ⅲ) cryptate resulted in blue-shift of three ligand-centered bands, increase of molar absorption coefficient and increase of the luminescence intensity of Eu(Ⅲ ).     

作为白光LED用铕掺杂氟化镧红色荧光粉的制备与光谱性能研究

采用水热法制备具有单一相六方晶系的LaF₃:Eu3+纳米荧光粉.通过X射线粉末衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、光致发光光谱(PL)和荧光衰减曲线对LaF₃:Eu3+纳米荧光粉进行表征.LaF₃:Eu3+荧光粉的激发光谱主要由250 nm处的宽带(O2-→Eu3+的电荷转移跃迁)和一些尖峰(Eu3+ f-f跃迁)构成,其中位于近紫外区396 nm处有一较强的激发峰.通过发射光谱探测Eu3+在LaF₃晶体中的局部晶场环境.在298 K下激发光谱和发射光谱可知,在六方晶系的LaF₃纳米晶体中的Eu3+晶格位置从D_4h降至到C_2v,这是由于晶格变化所造成的.在396 nm激发下,观测到较优掺杂浓度为10%的LaF₃:Eu3+荧光粉在591 nm(5D₀→7F₁跃迁)处有强烈的红色发射峰.其发光性能表明,LaF₃:Eu3+红色荧光粉在近紫外发光二极管领域具有潜在的应用价值.      

Crystal Structure and Luminescence Property of Lanthanide Complexes with 2-Fluorobenzoic Acid and 2,2''-Bipyridine

The two compounds of [Ln(2-FBA)3·2,2'-bpy]2 (2-FBA=2-fluorobenzoato, 2,2'-bpy=2,2'-bipyridine, Ln=Eu(1), Dy(2)) were synthesized and their structures were determined by X-ray diffraction method. Crystallized complexes 1 and 2 are isomorphous, monoclinic system with P21/n space group. The two complexes are binuclear molecule with an inversion center. The two lanthanide ions are linked by four bridged 2-FBA ligands and each lanthanide ion is further bonded to one chelated bidentate 2-FBA ligand and one 2,2'-bipyridine molecule. The coordination number of metal ion is eight. The europium complex exhibits strong red fluorescence. 5D0→7Fj (j= 1～4) transition emission of Eu3 ion was observed.     

Synthesis and Characterization of Rare Earth Complexes of Ferrocenylcarbonylhydrazine

Ｔｈｅｍｅｔａｌｃｏｍｐｌｅｘｅｓｏｆｈｙｄｒａｚｉｄｅｓｈａｖｅａｔｔｒａｃｔｅｄｃｏｎｓｉｄｅｒａｂｌｅｉｎｔｅｒｅｓｔｏｗｉｎｇｔｏｔｈｅｉｒａｎｔｉｆｕｎｇａｌａｎｄａｎｔｉｂａｃｔｅｒｉａｌａｃｔｉｖｉｔｉｅｓ[1 ,2 ] .Ｔｈｅｙｃａｎａｌｓｏｂｅｕｓｅｄａｓａｎａｌｙｔｉｃａｌｒｅａｇｅｎｔｓ[3 ]ａｎｄｅｘｔｒａｃｔｉｎｇａｇｅｎｔｓｆｏｒｍｅｔａｌｓａｌｔｓ[4 ] .Ｍａｎｙｃｏｍｐｌｅｘｅｓｏｆｈｙｄｒａｚｉｄｅｓｈａｖｅｂｅｅｎｓｙｎｔｈｅｓｉｚｅｄａｎｄｃｈａｒａｃｔｅｒｉｚｅｄ[5]…     

Anneal and Concentration Effect on PL Properties of Sol-Gel Derived Eu3+ Doped SiO2 Glass

Eu3 doped SiO2 nano-crystalline glasses were prepared by sol-gel method. The broad peak of XRD pattern indicates an amorphous SiO2 matrix. The affection of anneal time and anneal temperatures on photoluminescence (PL) properties of SiO2 glass under different Eu3 doping concentration were studied systematically. It is found that the optimized anneal time is about 3 h. The excitation spectra of 2% Eu3 doped SiO2 glass powder were measured under various anneal temperatures, and the optimized anneal temperature is observed around 700 ℃. The fluorescence-quenching effect can be observed in the emission spectra when the annealing temperature exceeds 700 ℃. The emission spectra of different molar ratio dopants were measured at an annealed temperature of 500 ℃, and the concentration-quenching phenomenon has also been observed in SiO2 glass powder when the molar ratio of Eu3 ion exceeds 3%. The result shows that the PL intensity approaches its maximum when the molar ratio of Eu3 ions in the sample is about 3%. In addition, a comparatively stronger emission spectrum at wavelength of 703 nm which is corresponding to the energy transition 5D0→7F4 of Eu ions is also obtained.     

Syntheses and Characterization of Binuclear Complexes Tb（1-x）Eux（TTA）3 Phen

Rare earth ternary complexes Tb1-xEux（TTA）3Phen（x=0,0.25,0.5,0.75,1.0）were synthesized and characterized by DTA-TG,XRD and infrared（IR）.The photophysical properties of these complexes were studied in detail using ultraviolet absorption spectra and fluorescent spectra.Ultraviolet absorption showed that the energy absorption of the complexes mostly came from ligands.Infrared spectra of Tb1-xEux（TTA）3Phen complexes were similar to the pure complexes.TG curves proved that the complexes were stable.Tb3＋ emission was almost quenched and the Eu3＋ emission was enhanced by codoping the complexes.The Tb3＋ ion acted as an energy transfer bridge that helped energy transfer from poly（N-vinylcar-bazole（PVK）to Eu3＋.In addition,their PL and EL properties were systematically studied.     

Synthesis, Characterization and Fluorescence Properties of Europium, Terbium Complexes with Biphenyl-4-Carboxylic Acid and o-Phenanthroline

Two series of solid complexes of europium and terbium with biphenyl 4-carboxylic acid and phen were synthesized and characterized in this report. Their elemental analysis, molar conductivities and TG-DTA studies indicate that the complexes have the composition of Eu(phen)L3·1/2H2O, Eu0.5RE0.5(phen)L3·1/2H2O; Tb(phen)L3·H2O and Tb0.5RE0.5(Phen)L3·1/2H2O. (RE=Y3 , La3 and Gd3 ; L=biphenyl 4-carboxylic acid; phen=o-Phenanthroline). The studies of their IR, UV 1H NMR and molar conductivities demonstrate that biphenyl 4-carboylic acid is bounded with RE(Ⅲ) ion. Rare earth ions coordinate with two nitrogen atoms of phen molecules directly in these rare earth complexes. The fluorescence spectra and fluorescence lifetimes of the rare earth complexes show that the fluorescent intensity and lifetime of a series of europium complexes are longer than those of the series of terbium complexes as having the some ligands. There are better fluorescent intensity and lifetime of hetero-nuclear rare earth complexes than homo-nuclear rare earth complexes for europium complexes. The fluorescence emission intensity of Eu3 is raised by inert fluorescent rare earth ions (Y3 , Gd3 and La3 ), but in Tb3 hetero-nuclear rare earth complexes the intensity of Tb3 ions are quenched by the inert fluorescent rare earth ions.