检索结果-南通市图书馆

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

Preparation and luminescence properties of Eu^(2+)-doped CASN-sinoite multiphase system for LED

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2010年第S1期28卷 289-291页

作者：申颖庄卫东刘元红何华强何涛 National Engineering Research Center for Rare Earth Materials Grirem Advanced Materials Co.Ltd.General Research Institute for Nonferrous Metals

A series of Eu2+-doped CASN-sinoite multiphase system with a formula of(CaAlSiN3)(1-x)-(Si2N2O)x were successfully synthesized by the high temperature solid-state *** crystal structure and morphology of the phosphors and their photoluminescence(PL) were *** the Eu2+-doped samples the PL intensity approached its maximum when the molar ratio of Si2N2O in the samples was about *** increase of the concentration of Si2N2O,the emission peak shifted from 645 to 605 *** was because the spectroscopic polarizability(αsp) became smaller with the increase of Si/Al ratio or the adding of O atoms,which caused the change of crystal field *** addition,the full width at half maximum(FWHM) widened with the increase of x value,which was favor of the improvement of the color rendering index.

关键词： LED CASN-sinoite multiphase system luminescence properties structure rare earths

Investigation of 2.9 μm luminescence properties and energy transfer in Tm^(3+)/Dy^(3+) co-doped chalcohalide glasses

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2011年第2期29卷 105-108页

作者：李忠秀徐铁峰沈祥戴世勋王训四聂秋华章向华 College of Information Science and Engineering Ningbo University College of Science Jiangxi Agricultural University Laboratoire de Verres et Ceramiques Universitè de Rennes I

A series of chalcohalide glasses based on the composition of 0.9（Ge30Ga5Se65）-0.1CsI with different Tm3＋/Dy3＋-codoped ions concentrations were synthesized by melt-quenching *** absorption spectra and 2.9 μm mid-infrared fluorescence spectra of glass samples under 800 nm laser excitation were *** results showed that Tm3＋ was an efficient sensitizer,which could enhance the Dy3＋： 2.9 μm fluorescence intensity *** effective energy transfer between the two rare-earth ions were mainly attributed to the resonance energy transfer from Tm3＋：3F4 to Dy3＋：6H11/2 *** cross section of 2.9 μm mid-infrared luminescence was also investigated according to Judd-Ofelt theory,σe=2.51×10–20 cm2.

关键词： chalcohalide glasses luminescence properties energy transfer Tm3+/Dy3+ rare earths

Effects of different ligands on luminescence properties of LaF_3:Nd nanoparticles

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2013年第7期31卷 645-649页

作者：桂珞崔晓霞韦玮彭波范滇元 Key Laboratory on High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences(CAS) State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academy of Sciences(CAS)

A series of neodymium-doped lanthanum fluoride nanoparticles （NPs） were synthesized with hydrothermal method, and the effects of several ligands on the luminescence properties of the NPs were investigated. The X-ray diffraction （XRD） results indicated that the crystal phases of the modified NPs coincided with the standard spectrum. The transmission electron microscopy （TEM） showed that the samples were of similar size, shape and dispersibility. The infi＇ared spectra suggested that the content of-OH groups as quenchers on the NPs surfaces decreased after modification. Compared with NPs modified by branched paraffin ligands, NPs conjugating ring-contained modifiers had less quenching effect and possessed stronger fluorescence intensity and longer fluorescence lifetime.

关键词： hydrothermal method luminescence properties modification nanoparticles rare earths

VUV luminescence properties of Y_(0.95)Eu_(0.05)PO_4 phosphor derived by a modified solid-state route

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2008年第4期27卷 354-357页

作者： ZHENG Cuihong ZHU Weichang WANG Lu School of Materials Science and Engineering and Anhui Key Laboratory of Metal Materials and Processing Anhui University of Technology Ma ＇anshan 243002 China

A modified solid-state route was attempted to prepare Y0.95 Eu0.05PO4 PDP phosphor, involving milling a powdered mixture of YCl3, EuCl3, and （NH4）2HPO4 and calcining the milling-derived precursor. The thermal decomposition behavior of the milling-derived precursor was investigated by thermogravimetric analysis （TGA）. Phase compositions, morphologies, and luminescence properties of the prepared phosphor powder were characterized by X-ray diffraction （XRD）, scanning electron microscope （SEM）, and vacuum ultraviolet （VUV） emission spectra, respectively. The results indicated that the Y0.95Eu0.05PO4 phosphor powder obtained at a calcination temperature of 900℃ was xenotime-structured. The phosphor powder particles were uniform and spherical-shaped with a primary particle size of-200 um. In comparison with that derived by the conventional solid-state route, the phosphor powder prepared by the modified solid-state route exhibited a higher color purity, presenting a predominant emission peak at 619 nm under 147 um VUV excitation.

关键词： phosphor luminescence properties vacuum ultraviolet solid-state reaction

luminescence properties and intramolecular energy transfer of europium (Ⅲ) complex in Langmuir-BIodgett film

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 1997年第6期 54-61页

作者：于安池应立明赵新生夏文胜黄春辉 Beijing 100871 China Department of Chemistry Peking University State Key Laboratory of Rare Earth Materials Chemistry and Applications

The fluorescence spectra of europium ( Ⅲ) complex in Langmuir-Blodgett film were obtained when the sample was irradiated by 355 nm UV light corresponding to a ligand π→π* transition at room temperature. A 115 cm -1 splitting of the 5D1 energy level of europium (Ⅲ) ion was observed. A datailed discussion of intramolecular energy transfer of europium ( Ⅲ ) complex in Langmuir-Blodgett film was given. On the basis of simulating the lifetime of 5D0 state of europium (Ⅲ ) ions, it was found that the population of 5D0 state comes from two pathways: one is directly from the ligand triplet state (T1), and the other is from 5D1 state which is also populated from the ligand triplet state (T1). The branching ratio for these two pathways is 0.18. The kinetics parameters of intramolecular energy transfer of europium (Ⅲ) complex in LB film were also derived.

关键词： europium (Ⅲ) complex luminescence properties intramolecular energy transfer LB film.

Synthesis,structure and luminescence properties of Tb4 and Eu4 clusters

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Synthesis,structure and luminescence properties of Tb4 and E...

Synthesis,crystal structure and photoluminescence properties of novel double perovskite La2CaSnO6:Eu3+red-emitting phosphors

中国晶体学会第六届学术年会暨会员代表大会（功能分子晶体...

作者： Wen-Min Wang Cai-Feng Zhang Department of Chemistry Taiyuan Normal University

Currently,the study of lanthanide-based functional complexes has become one of the research hotspots owing to their potential properties in catalysis,magnetism and luminescence.[1-3] In this paper,two Ln4 clusters,[Ln4（dbm）4（L）6（μ3-OH）2]·[solvent]（Ln = Tb（1） and Eu（2）,HL = 5-（4-methylbenzylidene）-8-hydroxylquinoline,dbm = 1,3-diphenyl-1,3-propanedione）（Fig.1）,have been synthesized by using solvent evaporation *** complexes were characterized by the single crystal X-ray diffraction,elemental analysis（EA）,powder X-ray diffraction（PXRD）,TG investigated,and further studied them by using luminescent *** properties studies reveal that 1 and 2 exhibit the characteristic emissions of TbIII and EuIII ions,respectively.（Fig.2）.

关键词： Tb4 and Eu4 clusters crystal structure luminescence properties

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Rare Earths 2022年第11期40卷 1682-1690,I0001页

作者： Yangyi Xu Guifang Li Xufeng Guan Yunge Wei Maolin Zhang School of Advanced Materials and Nano Technology Xidian UniversityXi'an710071China

A series of new double perovskite LaEuCaSnO(0≤x≤0.8)red phosphors were synthesized by traditional solid-state *** phase,micro structure,photoluminescence(PL)properties,quantum efficiency,and thermal stability of the phosphors were *** has a monoclinic double perovskite structure with space group P2/*** near-ultraviolet(UV)light at395 nm,LaEuCaSnOphosphors exhibit the most typical red emission peak at 614 nm,which corresponds to~5 D→~7 Felectric dipole transition of *** optimum Eudoping content is attained at x=0.5,and the LaEuCaSnOphosphor shows a moderate quantum efficiency(32.3%)and high color purity(92.2%).Besides,the temperature-dependent spectrum of the phosphor was *** emission intensity of Euat 423 K decreases to 70.94%of the initial intensity at 303 K,and the activation energyΔE is estimated to be 0.232 eV,suggesting that the phosphors possess good thermal *** fabricated w-LED based on the phosphors has higher Ra(89),lower CCT(4539 K),and better chromaticity coo rdinates(0.371,0.428).These results prove that the Eu-doped LaCaSnOred phosphor has great potential applications in w-LEDs.

关键词： Phosphors Double perovskite luminescence properties La2CaSnO6 Rare earths

Tunable emission,energy transfer and thermal stability of Ce^(3+),Tb^(3+) co-doped Na_(2)BaCa(PO_(4))_(2) phosphors

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2022年第6期40卷 878-887,I0002页

作者： Jiamin Tang Jiayong Si Xiaoyi Fan Yijia Liu Guihua Li Gemei Cai College of Mechanical and Electrical Engineering Central South University of Forestry and TechnologyChangsha 410004China School of Materials Science and Engineering Central South UniversityChangsha 410083China

A series of single Ce^(3+) doped and Ce^(3+) and Tb^(3+) co-doped Na_(2)BaCa(PO_(4))_(2)(NBCP) phosphors was synthesized by conventional solid-stated reaction *** crystal structure,luminescence properties,thermal stability and energy transfer were carefully ***^(3+) is inferred to substitute the Ba^(2+)site in NBCP *** color-tunable emission from blue to green is observed by adjusting Tb^(3+) concentration among NBCP:0.03 Ce^(3+),yTb^(3+) *** energy transfer behavior from Ce^(3+) to Tb^(3+) ions is both illustrated by co-doped PL spectra and decay *** energy transfer efficiency is as high as 91.5%.The mechanism of energy transfer is resonance type of dipole-dipole *** this work,the optimal phosphor exhibits the excellent thermal stability which keeps at 94.9% of that initial value at room temperature when temperature reaches to 150℃.The Ce^(3+) and Tb^(3+) co-doped NBCP phosphor is a promising candidate for the application in the general lighting and display fields.

关键词： Na_(2)BaCa(PO_(4))_(2) luminescence properties Energy transfer Tunable emission Thermal stability Rare earths

A novel blue-light excitable Pr^(3+)doped(Sr,Ba)LaMgTaO6 phosphor for plant growth lighting

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2023年第5期41卷 666-672,I0002页

作者： Xiaojiao Kang Wei Lü Zhennan Zhu Chuanyu Jia School of Electrical Engineering and Intelligentization Dongguan University of TechnologyDongguan 523808China

In this work,a series of Pr^(3+)ions doped(Sr,Ba)LaMgTaO_(6)phosphors were prepared and applied for plant growth *** 450 nm excitation,(Sr,Ba)LaMgTaO_(6):Pr^(3+)exhibits intense reddish emission at around 650 nm which is assigned to the3p0→3F2transition of Pr^(3+)*** luminescence intensity reaches to the maximum at 2.5 mol%Pr^(3+)doping content both in SrLaMgTaO_(6):Pr^(3+)and BaLaMgTaO_(6):Pr^(3+)***,the internal quantum efficiency(IQE)test shows that the IQE of the SrLaMgTaO_(6):0.025Pr^(3+)phosphor is 33.34%upon blue light *** decay curves and temperature-dependent luminescence measurements of the(Sr,Ba)LaMgTaO_(6):Pr^(3+)phosphors were performed and investigated in *** red light emitting diodes(LEDs)were packaged using the SrLaMgTaO_(6):Pr^(3+)and BaLaMgTaO_(6):Pr^(3+)phosphors combined with a blue LED chip,which are welloverlapped with the absorption band of *** indicate that the(Sr,Ba)LaMgTaO_(6):Pr^(3+)can serve as a component of the red light in plant-growth LEDs.

关键词： Phosphor luminescence properties Plant-growth LEDs Rareearths