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Crystal structure, morphology and luminescent properties of rare earth ion-doped SrHPO_4 nanomaterials

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Journal of rare earths 2015年第4期33卷 355-360页

作者：王梦楠田博士岳丹鲁伟于明丽李春阳李庆锋王振领 The Key Laboratory of rare earth Functional Materials and Applications Zhoukou Normal University Zhoukou 466001 China The College of Chemistry and Molecular Engineering Zhengzhou University Zhengzhou 450001 China Department of Applied Physics and University Research Facility in Materials Characterization and Device Fabrication The Hong Kong Polytechnic University Hong Kong China

Undoped and rare earth ions （Eu3＋, Ce3＋, Tb3＋） doped β-SrHPO4 nanomaterials were successfully prepared by a facile hydrothermal method. The crystal structure, morphology and luminescent properties were characterized by X-ray powder diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, photoluminescence （PL） spectra and lumi- nescence decay curves. The results indicated that the tmdoped and rare earth ions doped SrHPO4 nanomaterials （the doping concen- tration was not above 7%） were well crystallized, with the same crystal structure （^-SrHPO4）. Nevertheless, the doping of rare earth ions could lead to the changing of morphology from nanoflakes to nanocrystals. Under the excitation of UV light, rare earth ions （Eu3＋, Ce3＋, Tb3＋） doped I3-SrHPO4 nanocrystals exhibited the characteristic emission of Eu3＋, Ce3＋ and Tb3＋ ions, respectively. The luminescence decay curves of [3-SrHPO4：Eu3＋ and D-SrHPO4：Ce3＋,Th3＋ nanocrystals conformed to the double exponential fluores- cence decay, and the average lifetimes were 1.14 and 4.12 ms, respectively. The luminescence decay curve of 13-SrHPO4：Ce3＋ was fitted into a single exponential function, and the lifetime was about 0.78 ns.

关键词： β-SrHPO4 luminescent properties rare earth ion doping rare earths

STUDY ON POLYMER-rare earth METAL ion COMPLEXES Ⅰ. FLUORESCENT PROPERTIES OF POLY(ACRYLIC ACID-CO-4-VINYLPYRIDINE)-rare earth METAL COMPLEXES

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Chinese Journal of Polymer Science 1987年第3期 234-239页

作者：吕泓方世璧江英彦 Academia Sinica Beijing Institute of Chemistry

A kind of copolymer of acrylic acid and vinylpyridine was synthesized and the fluorescent properties of the complexes of the copolymer with Eu;or Tb;were studied. It was found that the fluorescence intensity of the complexes of the eopolymer with Eu;was 20 times as high as that of the complexes of polyaerylic acid with Eu;and twice as high as that of the complexes of polyvinylpyridine with Eu;. The effects of the composition of the copolymer and the content of Eu;or Tb;in the complexes were studied. The fluorescence lifetime of the complexes was measured and it was found that two or more kinds of energy transfer mechanism existed.

关键词： Poly (acrylic acid-co-4-Vinylpyridine) rare earth ion Complex Fluorescence

A Theoretical Model of Energy Transfer between rare earth ions in Crystals

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Chinese Journal of Structural Chemistry 2008年第8期27卷 975-979页

作者：林炎富罗遵度 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of SciencesFuzhou Fujian 350002 China

The limitation of the random walk theory of energy transfer between rare earth ions in crystals published in literatures is pointed out in this paper. A modified model, which can be used in any level of rare earth ion concentration when the interaction between donor and acceptor is different from that between donors, is introduced. measured fluorescence lifetimes of Yb^3＋：YAl3（BO3）4 This model has been applied to analyze the with a series of Yb^3＋ concentrations.

关键词： energy transfer rare earth ion theoretical model

Synthesis and Photocatalytic Activity of TiO_2/V_2O_5 Composite Catalyst Doped with rare earth ions

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Journal of rare earths 2007年第2期25卷 173-178页

作者：刘建华杨蓉李松梅 School of Materials Science and Engineering Beihang University

TiO2/V2O5 catalyst doped with rare earth ions was prepared by sol-gel method. Titanium tetrapropoxide and vanadium pentoxide were used as precursor of the composite catalyst and rare earth ions were used as dopant. The crystal phases, crystalline sizes, microstructure, absorption spectra of doped composite catalyst were studied by XRD, EDS, FT-IR and UV-Vis. Photoactivity of the prepared catalyst under ultraviolet irradiation were evaluated by degradation of methyl orange （MO） in aqueous solution. It is shown that the prepared catalyst is composed of anatase and futile. The rare earth ions are highly dispersed in composite catalyst. All the doped catalysts appear higher photocatalytic activity than TiO2/V2O5 catalyst and catalyst doped with Ce^4＋ present the best activity to MO.

关键词： photocatalysis titanium dioxide composite catalyst rare earth ion cerium

Energy transfer process of Nd^(3+)/Ho3+co-doped fluoride halide glasses with anion substituted multi-wavelength tunable mid-infrared luminescence

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Journal of rare earths 2021年第11期39卷 1344-1352,I0002页

作者： Hao Yin Xiaosong Zhang Lan Li Jiajia Zhang Zhaowei Zhang Xin Liu Xiaokai Gong Rukun Ding Key Laboratory of Display Materials and Photoelectric Devices Ministry of EducationTianjin Key Laboratory for Photoelectric Materials and DevicesNational Demonstration Center for Experimental Function Materials EducationInstitute of Material PhysicsSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

Ho^(3+)doped ZBLAN glass with 2.0 and 2.9μm emission was *** order to further improve the luminescence of Ho^(3+),halogen ions(Cl,Br,1)were introduced to reduce the maximum phonon energy and phonon state density of the *** the same time,Nd^(3+)was introduced to transfer the energy to Ho^(3+)pumped with a 793 nm laser(Nd^(3+):4 F5/2,4 F3/2→Ho^(3+):5 I6).The effect of different halogen ion on the luminescent properties of the fluoride halide glass was *** results show that the luminescent intensity of infrared increases with the introduction of different halogen *** comparison,it is found that the sample with I-has the strongest luminescence of 1064 nm,2.0μm and 2.9μ*** is consistent with the calculated J-O intensity *** addition,the 2.0 and 2.9μm emission of Ho^(3+)pumped with a 450 nm laser will not disappear.A mid-infrared sample with multi-wavelength excitation and multi-wavelength emission can be ***^(3+)/Ho^(3+)co-doped fluoride halide glasses with 1064 nm,2.0μm and 2.9μm luminescence were prepared by melt quenching *** luminescent mechanism and the energy transfer process between the two ions of Nd^(3+)/Ho^(3+)co-doped fluoride halide glass were *** J-O parameters,luminescence lifetime and absorption emission cross-sectional area of Ho^(3+)and Nd^(3+)were calculated,*** is found that the value ofΩ2 in the glass matrix increases with the introduction of different halogen ions,whileΩ4 andΩ6 do not change obviously in different glass *** is because the environment of the crystal field around the rare earth ions *** crystal phase and phonon energy of the sample were analyzed by X-ray diffraction pattern and a Fourier transform infrared spectrometer,*** on the above spectra and data(phonon energy is 634.71 cm-1),it can be predicted that Nd^(3+)/Ho^(3+)co-doped fluoride halide glass is a potential mid-infrared luminescent material.

关键词： Halogen ion substitution rare earth ion Multi-wavelength tunable Energy transfer mechanism Mid-infrared emission

Investigation of the red-shift of the emission of microwave solvothermally-grown europium doped calcium sulphide crystals

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Journal of rare earths 2014年第8期32卷 702-708页

作者：董晓菲陆启飞卢志娟毛智勇王达健 Institute of Materials Physics School of Materials Science and Engineering Tianjin University of Technology

A distinct red-shift to 660 nm-featured longer wavelength of europium doped calcium sulphide nanocrystals was observed in a microwave （MW）-assisted solvothermal synthesis procedure. This red-shift was probably due to a combined effect from Mg^2＋ codoping and strain accumulation at grain boundaries. The latter originated from the formation of small grains with an average size of around 200 nm in micrometer sized crystals upon Mg^2＋ codoping. In particular, MW electromagnetic field suppressed grain growth and enabled a reconstruction of atoms at the inner grain boundary at which the field strength was intensified around rare earth ions in host lattices. This MW synthesis route provided an option to prepare luminescent crystals with the desired blue-excitable longer wavelength emission.

关键词： rare earth ion calcium sulphide microwave solvothermal

Adsorption of La^(3+) and Ce^(3+) by poly-γ-glutamic acid crosslinked with polyvinyl alcohol

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Journal of rare earths 2015年第8期33卷 884-891页

作者：高玉千张世敏赵凯亚王志伟徐淑霞梁振普吴坤 College of Life Science Henan Agricultural University Key Laboratory of Enzyme Engineering of Agricultural Microbiology Ministry of Agriculture

With the exploitation of rare earth ore, more and more rare earth elements came into groundwater, caused waste of resources and toxicity to the organisms. This study aimed to find an efficient adsorption material to mitigate the above issue. Through doping polyvinyl alcohol with poly-γ-glutamic acid, an immobilised PSP gel particle was produced and had the adsorption rate of La3＋ up to 97.10%. The factors including initial concentration of La3＋ or Ce3＋, adsorbent dosage, pH and temperature of the solution, which potentially affected the adsorption rate and were studied in batch mode. It was found that the optimum adsorption conditions were composed of 50 mg/L La3 VCe3＋ of initial concentration, 600 mg/L （dry mass） biomass for adsorption, pH 6, temperature 30 ℃, 150 r/min rotational speed, and 1 h adsorption time. The selective adsorption of 15 different rare earth ions in mixed aqueous solu- tions were investigated. However, no significant selective differences were observed. Scanning electron microscopy showed that the morphological characteristic of the novel gel was its porous structure, while polyvinyl alcohol gel had a compact structure. Fourier transform infrared spectroscopy suggested that carboxyl groups in the poly-γ-glutamic acid might played a key role in the adsorption process. The adsorption mechanism forecasted to be cation exchange between -COOH and R3＋. The adsorption kinetic and thermodynamic process for La3＋ and Ce3＋ was consistent with the pseudo-second-order equation and Langmuir adsorption isotherm model. It demonstrated that PSP gels particles were useful for removing REEs from wastewater.

关键词： adsorption rare earth ion poly-γ-glutamic acid polyvinyl alcohol

Synthesis, fluorescence properties of Tb(Ⅲ) complexes with novel mono-substituted β-diketone ligands

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Journal of rare earths 2010年第5期28卷 671-675页

作者：罗一鸣李石凤李军陈学娟唐瑞仁 School of Chemistry and Chemical Engineering Central South University

Two novel pyridine-2,6-dicarboxylic acid derivatives of mono-β-diketone named methyl 6-biphenylacetyl-2-pyridinecarboxylate (MBP) and 6-biphenylacetyl-2-pyridinecarboxylic acid (BAA) and their corresponding binary complexes Tb(MBP)3.6H2O and Tb(BAA)3·6H2O were synthesized. The ligands were characterized by elemental analysis, FT-IR and 1H-NMR, and the complexes were characterized with elemental analysis, FT-IR, 1H-NMR and thermogravimetric and differential thermal analysis(TG-DTA). The investigation of fluo...

关键词： organic ligand mono-β-diketone synthesis fluorescence property rare earth ion

Synthesis and Magnetic Properties of Polyamide Complex Containing Bithiazole Moieties

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Chinese Chemical Letters 2005年第8期16卷 1113-1116页

作者： Hong Zhou GAO Wei Lin SUN Zhi Quart SHEN Department of Polymer Science and Engineering Zhejiang University Hangzhou 310027

A new polyamide containing bithiazole moieties （PTA） was synthesized by the polycondensation of 2, 2＇-diamino-4, 4＇-bithiazole （DABT） and oxalyl chloride. The polymer complex was prepared from PTA and NdC13 in DMSO. They were characterized through IR and elemental analysis. The preliminary magnetic properties of the complex PTA-Nd^3＋ was investigated, it was found that the material is a ferromagnet at low temperature.

关键词： Polyamide bithiazole rare earth ion magnetic property.