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luminescence properties of Tb^(3+)-Doped LuAG Films Prepared by Pechini Sol-Gel Method

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Journal of Rare Earths 2006年第6期24卷 745-748页

作者：游宝贵尹民张慰萍郭海林林 Structure Research Laboratory Chinese Academy of Sciences Hefei 230026 ChinaPhysics Department University of Science and Technology of China Hefei 230026China Department of Physics Zhejiang Normal University Jinhua 321004China Physics Department University of Science and Technology of China Hefei 230026China

Lu3Al5O12（LuAG） thin films with different Tb^3＋ concentration were prepared on carefully cleaned （111 ） silicon wafer by a Peehini process and dip-coating technique. Heat treatment was performed in the temperature range from 800 to 1100 ℃. The crystal structure was analyzed by XRD. The results show that LuAG film starts to crystallize at about 900 ℃, and the particle size increases with the sintering temperature. Excitation and emission spectra of Tb^3＋ doped LuAG films were measured. The effects of heat-treatment temperature and doping concentration of Th3 ＋ on the luminescent properties were also investigated. For a comparison study, Th^3＋-doped LuAG powders were also prepared by the same sol-gel method.

关键词： sol-gel LuAG luminescence properties thin film concentration dependence rare earths

luminescence properties of Sm^(3+) doped Bi_2ZnB_2O_7

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Journal of Rare Earths 2006年第4期24卷 392-395页

作者：张秋红王静张梅丁唯嘉苏锵 State Key Laboratory of Optoeletronic Materials and Technologies School of Chemistry and Chemical Engineering Sun Yat-Sen University Guangzhou 510275China

The phosphors of （Bi1- x Smx ） 2ZnB2O7 （ x = 0. 01, 0. 03, 0. 05, 0. 07, and 0. 09） were synthesized by conventional solid state reaction. The purity of all samples was checked by X-ray powder diffraction （XRD）. XRD analysis shows that all these compounds are of a single phase of Bi2ZnB2O7, indicating that the Bi^3＋ in Bi2ZnB2O7 can be partly replaced by the Sm^3＋ without the change of crystal structure. The excitation and emission spectra at room temperature show the typical 4f-4f transitions of Sm^3＋ . The dominant excitation line is around 404 nm due to ^6H5/2→^4K11/2 and the emission spectrum consists of a series of lines at 563, 599, 646, and 704 nm due to ^4G5/2→^6H5/2, ^6H7/2, ^6H9/2, and ^6H11/2, respectively. The optimal concentration of Sm^3＋ in Bi2ZnB2O7 is about 3mol% （relative to lmol Bi^3＋） and the critical distance Rc was calculated as 2.1 nm. The temperature dependence of the emission intensity of Bi1.94Sm0.06ZnB2O7 was examined in the temperature range between 100 and 450 K. The quenching temperature where the intensity has dropped to half of the initial intensity is 280 K. The lifetime for Sm^3＋ in Bi1.94Sm0.06ZnB2O7 is fitted as a value of 0.29 and 1.03 ms.

关键词： Bi2ZnB2O7 Sm^3+ luminescence properties concentration quenching thermal quenching rare earths

luminescence properties of BaAl_(12)O_(19):Tb,Ce and energy transfer between Ce^(3+),Tb^(3+)

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Journal of Rare Earths 2010年第S1期28卷 229-231页

作者：肖林久谢颖贺明睿陈永杰李文泽于维珂 Shenyang University of Chemical Technology Key Laboratory of Rare-Earth Chemistry and Applying Liaoning Province Shenyang Supervision and Inspection Institute for Product Quality

Ba0.9-ySryAl12O19:Eu0.1 phosphors were prepared by sol-gel technique,the crystalline structures of samples characterized by XRD,and the luminescence properties were *** influence of crystallographic positions on the luminescent properties of Sr2+-doped BaAl12O19:Eu was investigated in *** results indicated that the crystal lattice of BaAl12O19:Eu was not influenced by the Sr2+ and doping Sr2+ in BaAl12O19:Eu enhanced the luminescent properties of the phosphors at the proper concentration of Sr2+.With the increasing of concentration of Sr2+ doped in BaAl12O19:Eu,the relative luminescent intensity of Ba0.9-ySryAl12O19:Eu0.1 strengthened and blue-shifted.

关键词： phosphors luminescence properties Sr2+ Eu2+ rare earths

The luminescence properties and Intramolecular Energy Transfer of Rare Earth Complexes with Aromatic Carboxylic Acids

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Chemical Research in Chinese Universities 1998年第3期14卷 23-27页

作者： YAN Bing ZHANG Hong-jie NI Jia-zuan Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022

The triplet state energies of para aminobenzoic acid and nicotinic acid were determined by means of low temperature phosphorescence spectrometry. The energy matches between them and the resonant emitting energy levels of Eu 3+ , Tb 3+ , Sm 3+ , Dy 3+ were studied. The intramolecular energy transfer processes from the two aromatic carboxylic acid ligands to rare earth ions were also discussed on the basis of the measurement results of luminescence intensities, lifetimes and quantum efficiencies.

关键词： luminescence properties Intramolecular energy transfer Rare earth complexes

Stability and luminescence properties of CsPbBr_(3)/CdSe/Al core-shell quantum dots

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Chinese Physics B 2022年第4期31卷 525-533页

作者：姚恒陆安江白忠臣蒋劲国秦水介 Guizhou Province Key Laboratory for Photoelectric Technology and Application Guizhou UniversityGuiyang 550025China College of Medicine Guizhou UniversityGuiyang 550025China

To improve the stability and luminescence properties of CsPbBr_(3)QDs,we proposed a new core-shell structure for CsPbBr_(3)/CdSe/Al quantum dots(QDs).By using a simple method of ion layer adsorption and a reaction method,CdSe and A1 were respectively packaged on the surface of CsPbBr_(3)QDs to form the core-shell CsPbBr_(3)/CdSe/Al *** one week in a natural environment,the photoluminescence quantum yields of CsPbBr_(3)/CdSe/Al QDs were greater than 80%,and the PL intensity remained at 71%of the original ***,the CsPbBr_(3)/CdSe/Al QDs were used as green emitters for white light-emitting diodes(LEDs),with the LEDs spectrum covering 129%of the national television system committee(NTSC)standard color *** core-shell structure of QDs can effectively improve the stability of CsPbBr_(3)QDs,which has promising prospects in optoelectronic devices.

关键词： luminescence properties stability CsPbBr_(3)/CdSe/Al quantum dots(QDs) CsPbBr_(3)QDs

Preparation,structure,luminescence properties of europium doped zinc spinel structure green-emitting phosphor ZnAl_2O_4:Eu^(2+)

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Journal of Rare Earths 2018年第9期36卷 931-938页

作者： Can He Haipeng Ji Zhaohui Huang Xiaoguang Zhang Yan'gai Liu Minghao Fang Xiaowen Wu Xin Min Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of Geosciences

The Zn1-xAl2 O4：xEu2＋ phosphor powders were synthesized by the solid-state reaction *** synthesis temperature for ZnAl2 O4 was optimized,whereas the phase structure,TEM images,photoluminescence（PL） properties,the concentration quenching mechanism,the fluorescence decay curves,as well as the CIE chromaticity coordinates of the samples were investigated in *** the excitation at 379 nm,the phosphor exhibits an asymmetric broad-band green emission with a peak at 532 nm,which is ascribed to the 5 d-4 f transition of Eu2＋.When the doping concentration of Eu2＋ ions is 0.01,the luminescence intensity of the sample reaches the maximum *** is further proved that the exchange interaction results in the concentration quenching of Eu2＋ in the Zn1-xAl2 O4：xEu2＋ phosphor *** thermal quenching property of ZnAl2 O4：Eu2＋phosphor was investigated and the quantum efficiency（QE） values of the selected Zn0.99Al2 O4：0.01 Eu2＋ phosphor was measured and determined as 54.85%.The lifetime of the optimized sample Zn0.99Al2 O4：0.01 Eu2＋ is 3.0852 μs and the CIE coordinate of the sample was calculated as（0.3323,0.5538） with high-color-purity green *** properties indicate that the green-emitting ZnAl2 O4：Eu2＋ phosphor powder has potential application in white LEDs.

关键词： Zinc spinel Europium luminescence properties Green-emitting Rare earths

Tunable electronic band structure,luminescence properties and thermostability of(Gd_(1-x)La_(x))_(2)Si_(2)O_(7):Ce scintillator by adjusting La/Gd ratio

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Journal of Rare Earths 2021年第6期39卷 657-665,I0002页

作者： Qinhua Wei Zhenzhen Zhou Weijie Zhang Gao Tang Qian Liu Laishun Qin Hongsheng Shi College of Materials and Chemistry China Jiliang UniversityHangzhou 310018China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Xinjiang Technical Institute of Physics&Chemistry Chinese Academy of SciencesUrumqi 830011China

Mixed crystal strategy is an effective approach of improving the luminescence properties of optical materials and has been adopted widely in many *** this paper,the La-mixed Gd_(2)Si_(2)O_(7):Ce polycrystalline samples were successfully synthesized by a sol-gel *** crystal structure and luminescence properties were confirmed and discussed by XRD,UV-Vis luminescence spectra,and XEL,*** vacuum ultraviolet excitation spectra and thermoluminescence glow curves were also systematically investigated and discussed at varied temperature.A combination of the first-principles calculations and optical characterization experiments was employed to study the electronic band structure of host material,revealing that the band gap is narrowed and the 5d_(1) level of Ce^(3+) shifts to higher energy as the La content *** luminescence the rmo-stability and activation energy were also measured and *** indicates that thermo-stability is strongly dependent on the La *** effective approach is developed to tune the electronic band structure,luminescence properties and thermostability of(Gd_(1-x)La_(x))_(2)Si_(2)O_(7):Ce scintillator by adjusting La/Gd ratio.

关键词： First-principles calculations Scintillator (Gd_(1-x)La_(x))_(2)Si_(2)O_(7):Ce Band structure tunable luminescence properties Rare earths

Synthesis and luminescence properties of CdSe:Eu NPs and their surface polymerization of poly(MMA-co-MQ)

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Journal of Rare Earths 2018年第9期36卷 946-953页

作者： Junfang Gao Junhong Yang Shengli Yong Lijing Liu Xingwang Liu Department of Chemistry Baotou Teachers College

CdSe：Eu nanoparticles（NPs） were synthesized using an oil phase method and the substitution of Cd2＋with Eu3＋ was confirmed by XRD,TEM,UV-Vis absorption and fluorescence emission *** CdSe：Eu NPs are monodispersed and uniform spherical particles with a diameter of 3.2 nm,bigger than the pure CdSe NPs（2.3 nm）,but with a similar cubic structure as CdSe *** with those of pure CdSe NPs,both emission spectrum and absorption spectrum of CdSe：Eu NPs are *** CdSe：Eu NPs are incorporated into poly（MMA-co-MQ） to afford poly（MMA-co-MQ）-CdSe：Eu NPs with the cubic structure and particle size（～3-4 nm） similar to those of CdSe：Eu *** TEM imaging suggests that the CdSe：Eu NPs are uniformly dispersed in poly（MMA-co-MQ,） without any obvious *** fluorescent emission peak and absorption peak of poly（MMA-co-MQ）-CdSe：Eu NPs are between those of CdSe：Eu NPs and poly（MMA-co-MQ）,possibly due to the energy transfer caused by the interactions of Cd or Eu atoms on the surfaces of CdSe：Eu NPs with the N and O atoms of poly（MMA-co-MQ）.These CdSe：Eu and poly（MMA-co-MQ）-CdSe：Eu NPs with tunable photoluminescence properties can be potentially used for the fabrication of optical and optoelectronic devices.

关键词： CdSe:Eu NPs Doped Poly(MMA-co-MQ) Surface polymerization luminescence properties Rare earths

Structures and luminescence properties of Yb^(3+) in the double perovskites Ba_2 YB'O_6 (B'=Ta^(5+),Nb^(5+) phosphors

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Chinese Physics B 2011年第1期20卷 493-500页

作者：周文龙张庆礼高进云刘文鹏丁丽华殷绍唐 Anhui Provincial Key Laboratory of Photonic Devices and Materials Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences

The Yb3＋ doped Ba2YB＇O6 （B＇= Ta5＋, Nb5＋） were prepared by high temperature solid-state reaction method, their structures were determined by x-ray diffraction and refined by Rietveld method. The diffuse reflection absorption, excitation and emission spectra of yb3＋：Ba2YB＇O6 （B＇= Ta5＋, Nb5＋） were measured at room temperature. Under the excitation of ultraviolet light, these phosphors exhibit broad charge transfer band emissions of TaO6 or NbO6 centre with large Stokes shift. The Yb3＋ doped into these hosts are situated at y3＋ sites of cubic symmetry （Oh）. The experimental energy levels of Yb3＋ in Ba2YTaO6 and Ba2YNbO6 were determined by photoluminescence and diffuse reflection absorption spectra. Their wavefunctions and theoretical energy levels were obtained by diagonalising the Hamiltonian matrix. The experimental energy levels were fitted by Levenberg-Marquardt iteration algorithm to determine crystal field parameters. Then, the magnetic-pole transition line strengths of yb3＋：Ba2YB＇O6 （B＇=Ta5＋, Nb5＋） from （2F5/2）Г8-to the low-energy states were calculated.

关键词： luminescence properties Yb3+ Ba2YTaO6 Ba2YNbO6