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1.  Vacuum Ultraviolet Excited Photoluminescence Properties of Y2O2S:Eu^3+,Bi^3+ Phosphor  
   WANG Zhi-long WANG Yu-hua ZHANG Jia-chi《高等学校化学研究》,2008年第24卷第6期
   As an Hg-free lamp using phosphor, the Bi^3+ and EH^3+ co-doped Y2O2S phosphors were prepared and their luminescence properties under vacuum ultraviolet(VUV) excitation were investigated. The VUV photoluminescent intensity of Y2O2S:Eu^3+ was weak, however, considerably stronger red emission at 626 nm with good color purity was observed in Y2O2S:Eu^3+,Bi^3+ systems. Investigation on the photoluminescence reveals that the strong VUV luminescence of Y2O2S:Eu^3+,Bi^3+ at 147 nm is mainly because the Bi^3+ acts as a medium and effectively performs the energy transfer process: Y^3+-O^2-→Bi^3+→Eu^3+, while the intense emission band at 172 nm is attributed to the absorption of the characteristic ^1So-^1P1 transition of Bi^3+ and the direct energy transfer from Bi^3+ to Eu^3+. The Y2O2S:Eu^3+,Bi^3+ shows excellent VUV optical properties compared with the commercial (Y,Gd)BO3:Eu^3+. Thus, the Y2O2S:Eu^3+,Bi^3+ can be a potential red VUV-excited candidate applied in Hg-free lamps for backlight of liquid crystal display.    

2.  Effects of flux on crystal structure and luminescent properties of nitroxides phosphors  
   An Xie  Yu Shi  YuWei Wang《中国科学:物理学 力学 天文学(英文版)》,2014年第57卷第12期
   Yellow-green-emitting Sr Si2O2N2:Eu2+phosphors were synthesized with Sr2Si O4:Eu2+as precursor.The effects of flux and the concentration of Eu2+on the crystal structure and luminescent properties of the phosphors were investigated.Results suggested that the optimal content of flux Na2CO3 was 1 wt%and the optimal doping concentration of Eu2+was 0.05 mol.The emission spectra showed the most intense peaks located at 535 nm which corresponded to the 4f65d→4f7 transition of Eu2+.The excitation spectra showed that these phosphors could be effectively excited by near-ultraviolet and blue light,whichwas consistent with the widely applied output wavelengths of near-ultraviolet and blue-white light-emitting diode(LED)chips.When the influence of flux on the luminescent properties of Sr Si2O2N2:Eu2+phosphor was analyzed,the X-ray diffraction(XRD)patterns indicated that the flux could help the crystallization of the phosphors.No other phases except the triclinic structure of Sr Si2O2N2 were formed.The thermal stability and the emission intensity of synthesized Sr Si2O2N2:Eu2+phosphor were examined and compared with commercial YAG yellow phosphors.All results indicate that the yellow-green-emitting phosphor is a suitable candidate for the fabrication of white LEDs.    

3.  Morphology and photoluminescence of BaAl12O19:Mn2+ green phosphor prepared by flux method  
   周峻  王育华  刘碧桃  刘吉地《中国物理 B》,2010年第19卷第12期
   This paper reports that the green phosphor BaAl11.9O19:0.1Mn2+ is prepared by a flux assisted solid state reaction method.The effect of flux systems on the crystal structure,morphology and luminescent properties of the phosphor are studied in detail.The samples are characterized by the application of x-ray diffraction patterns,scanning electron microscopy patterns,luminescent spectra and decay curves.The results show that a pure phase BaAl12O19 can be achieved at the firing temperature above 1300℃ by adding the proper flux system,the firing temperature is reduced at least 200℃ in comparison with the conventional solid state reaction method.Maximum photoluminescence emission intensity is observed at 517 nm for(AlF3+Li2CO3) flux system under vacuum ultraviolet region(147 nm) excitation.The photoluminescence emission intensity and the decay time of these phosphor is found to be more superior to that of the corresponding sample prepared by the conventional solid state reaction method implying the suitability of this route for the preparation of display device worthy phosphor materials.    

4.  Synthesis and characterization of Sr3Al2O6:Eu2+, Dy3+ phosphors prepared by sol-gel-combustion processing  
   黄平  崔彩娥  王森《中国物理 B》,2009年第18卷第10期
   A type of red luminescent Sr3Al2O6:Eu2+, Dy3+ phosphor powder is synthesised by sol-gel-combustion processing, with metal nitrates used as the source of metal ions and citric acid as a chelating agent of metal ions. By tracing the formation process of the sol-gel, it is found that it is necessary to reduce the amount of NO3- by dropping ethanol into the solution for forming a stable and homogeneous sol-gel. Thermogravimetric and Differential Scanning Calorimeter Analysis, x-ray diffractionmeter, scanning electron microscopy and photoluminescence spectroscopy are used to investigate the luminescent properties of the as-synthesised Sr3Al2O6:Eu2+, Dy3+. The results reveal that the Sr3Al2O6 crystallises completely when the combustion ash is sintered at 1250 C. The excitation and the emission spectra indicate that the excitation broadband lies mainly in a visible range and the phosphors emit a strong light at 618 nm under the excitation of 472 nm. The afterglow of (Sr0.94Eu0.03Dy0.03)3Al2O6 phosphors sintered at 1250 ℃ lasts for over 1000 s when the excited source is cut off.    

5.  Luminescent Properties of Eu^3+—Doped Yttrium Oxide Chloride Embedded in Nanoporous Glass  
   曾小青 袁绥华 等《中国物理快报》,2002年第19卷第11期
   The photoluminescence of Eu^3 -doped yttrium oxide chloride embedded in nanoporous glass has been observed.In comparison with those in the powder phosphor,the emission lines of Eu^3 ions becom much broader and lueshift was observed in the lines due to ^5D0→^7F2 transitions and the Eu-O charge transfer excitation band.The ratio intensities of the ^5D0→^7F1 transitions to the ^5D0→^7F2 transitions of Eu^3 ion become higher and change at different excitation excitation wavelengths,such as 393nm and 254nm.The two excitation wavelengths belong to the 4f→4f transition of the Eu^3 ion and the Eu-O charge transfer,respectively,This material may be developed into a new luminescent glass.    

6.  助熔剂法制备的LaMgAl11O19∶Eun+(n=2,3)的发光特性  
   徐进章  张志华  王育华《无机化学学报》,2006年第22卷第5期
   LaMgAl11O19∶Eun+(n=2,3) was synthesized by solid state reaction using H3BO3 as a flux at 1 400 ℃ for 4 hours. And their luminescent properties was investigated under UV and VUV excitation. Strong pure blue emission due to d-f transition of Eu2+ was observed in LaMgAl11O19∶Eu2+ both in 254 nm and 147 nm excitation. At the same time, red emission due to 5D07FJ (J=0, 1, 2, 3, 4) transition of Eu3+ also observed in LaMgAl11O19∶Eu3+. The dependence of emission intensity of blue/red emission on Eu2+ / Eu3+-content was evaluated. The result indicated that the blue emission intensity was arrived optimum when Eu2+-content was 0.10 mol·mol-1under both UV and VUV excitation while red emission intensity reached optimum when Eu3+-content was 0.125 mol·mol-1 under UV excitation. This suggests that LaMgAl11O19∶Eu2+ phosphors could be potential blue phosphor for the application in PDP.    

7.  Sr3SiO5∶Eu2+荧光粉的微波合成及性能研究  
   刘全生  郝新焱  许国锋      曹丹丹      张希艳  孙海鹰《无机化学学报》,2010年第26卷第7期
   Silicate orange yellow phosphor used in white-light LED was prepared by microwave method. The structure and optical properties of phosphor were studied. Sr3SiO5∶Eu2+ phosphor synthesized by microwave method is tetragonal structure of Sr3SiO5 with uniform particle distribution. Luminescence spectrum is a broad band spectrum peaking at 575 nm. The peak of excitation is at 532 nm and phosphor can be excited by blue LED. The warm white light was obtained combined phosphor and blue LED. The CIE chromaticity coordinates and correlated color temperature of white light is (x=0.394, y=0.341) and 3 239 K respectively.    

8.  M3La(BO3)3(M=Ca,Sr,Ba)基质中Eu3+的光致发光  被引次数:1
   李其华  彭夷安  曹小妹  刘利民  朱小娟  雷春华《光谱实验室》,2004年第21卷第1期
   研究了M3La(BO3)3(M=Ca,Sr,Ba)基质中Eu3+的激发光谱和发射光谱.结果表明,最强激发峰均为394nm,并均有λ<300nm的较强电荷迁移带;按Ca-Sr-Ba的顺序,各发射峰峰值逐渐红移;Eu3+的最佳发射浓度分别为xEu3+=0.10、0.09、0.20;Eu3+的5D0→7F2跃迁发射的浓度猝灭机理分别为电偶极-四极、电偶极-偶极和电偶极-偶极相互作用.    

9.  Blue-to-Orange Tunable Luminescence from Europium Doped Yttrium--Silicon--Oxide--Nitride Phosphors  
   杨护成  ;李成宇  ;庞然  ;G.Lakshminarayana  ;周时凤  ;滕宇  ;邱建荣《中国物理快报》,2008年第25卷第9期
   Europium-doped yttrium-silicon-oxide-nitride phosphors are synthesized by carbothermal reduction and nitridation method. The crystal structure of the phosphors changed gradually from oxide Y2Si2O7 to nitride YSi3N5 state with increasing dosage of Si3N4 and carbon powder. The Y2Si2O7:Eu phosphor shows a blue emission at 465 nm with 300 nm excitation and a characteristic red emission of Eu^3+ at 612 nm with 230 nm excitation. The YSi3N5:EU phosphor shows a broad emission band centred at 595nm with some sharp peaks of Eu^3+ with 325nm excitation. The absorption of the studied phosphors increases from 450 to 700hm with an increment in nitrogen content. Blue-to-orange tunable luminescence is observed with 390 nm excitation.    

10.  Crystal Structure of Dimeric Units Cd2(ncpo)2(phen)2(H2O)2 Constructed by Flexible Dicarboxylic Acid with Fluorescent Emission  
   杨利  于伟  张同来  张建国  刘振华  吴瑞风《结构化学》,2009年第28卷第4期
   A dimeric coordination complex Cd2(ncpo)2(phen)2(H2O)2 was constructed by a flexible dicarboxylic acid, 2-nitro-4-carboxylphenoxyacetic acid. Its crystal structure was determined by X-ray single-crystal diffraction analysis. The crystal is of monoclinic system, space group P21/n with a = 17.2616(3), b = 12.7460(2), c = 18.4041(3) A^°, β= 94.432(1)°, C42H30Cd2N6O16, Mr = 1099.52, V = 4037.09(12)A^°^3 Dc = 1.809 g/cm^3, F(000) = 2192, μ = 1.139 cm^-1 and Z = 4. The final R = 0.0218 and wR = 0.0703 for 8288 observed reflections with I 〉 2σ(I). There are two crystallographically independent but structurally very similar molecules in the unit cell of the title complex. It is noticeable that the ligand ncpo^2- displays a good flexibility, demonstrating different modes from the rigid ligands. The luminescence property has been investigated, which shows photoluminescence at 465, 490 and 574 nm upon excitation at 320 nm in the solid state at room temperature.    

11.  Preparation and Luminescence Characteristics of Ca3Y2(BO3)4:Eu^3+ Phosphor  
   李盼来 杨志平 王志军 郭庆林《中国物理快报》,2007年第24卷第10期
   Ca3Y2 (BO3)4:Eu^3+ phosphor is synthesized by high temperature solid-state reaction method, and the Iuminescence characteristics are investigated. The emission spectrum exhibits two strong red emissions at 613 and 621 nm corresponding to the electric dipole ^5 Do- ^7F2 transition of Eu^3+ under 365 nm excitation, the reason is that Eu^3+ substituting for Y^3+ occupies the non-centrosymmetric position in the crystal structure of Ca3 Y2 (BO3)4. The excitation spectrum for 613 nm indicates that the phosphor can be effectively excited by ultraviolet (UV) (254 nm, 365nm and 400nm) and blue (470nm) light. The effect of Eu^3+ concentration on the emission intensity of Ca3 Y2 (BO3)4 :Eu^3+ phosphor is measured, the result shows that the emission intensities increase with increasing Eu^3+ concentration, then decrease. The CIE colour coordinates of Ca3Y2 (BO3)4:Eu^3+ phosphor is (0.639, 0.357) at 15mol% Eu^3+.    

12.  Synthesis and Luminescent Properties of Novel Nanometer-sized ScAlMgO_4:Eu~(3+) Phosphors for PDP  
   YUAN Tao-Sheng  ZHOU Hai-Tao  ZOU Yu-Qi《结构化学》,2010年第29卷第6期
   Novel nanometer-sized ScAlMgO4:Eu3+ phosphors were successfully synthesized by the citric acid complexation method.The mean particle size of the obtained powders was within the range of 100~150 nm according to the SEM patterns.In ScAlMgO4:Eu3+ showed strong characteristic red emission,of which the maximum emission peak was located at 629 nm for ultraviolet(UV) excitation.The dependence of photoluminescence intensity on Eu3+ concentration was also studied in detail,and the emission intensity of Sc1-xEuxAlMgO4 was about 10% at optimized Eu3+ concentration.Furthermore,the luminescence decay measurements showed that the lifetimes of Eu3+ were in the range of millisecond.The obtained ScAlMgO4:Eu3+ phosphors with nanometer size and excellent luminescence efficiency would be potential red phosphors in plasma display panels.    

13.  Eu3+掺杂SiO2-B2O3-NaF玻璃的制备及发光性质  被引次数:1
   王喜贵  吴红英  赵斯琴  翁诗甫  吴瑾光《无机化学学报》,2004年第20卷第3期
   The Eu-doped SiO2-B2O3-NaF glass was prepared by sol-gel process, using tetraethoxy Silicane, boric acid and sodium fluoride as starting materials, 0.10 mol·L-1 EuCl3 solution as the dopant. The luminescent properties of Eu3+ doped SiO2-B2O3-NaF phosphors were investigated. The phosphors showed prominent luminescence in pink, the strong emission of Eu3+ comes from electronic transition of 5D0- 7F1(591 nm)and 5D0- 7F2(615 nm),which derived from two transition modes of magnetic-dipole and electric-dipole .The peak intensity of 591nm in SiO2-B2O3-NaF matrix is much stronger than it in the other matrixes, it means that SiO2-B2O3-NaF has sensitization on the transition of 5D0- 7F1 (Eu3+). If there are broad bonds in the range of 275~380 nm in the excitation spectrum of Eu3+ -doped SiO2-B2O3-NaF glass, the emission peak intensity should be intensified. It is because the electron migration CT band of O2--Eu3+. For all Eu3+ concentrations used, the investigation found that when the mass of fraction got to 29.19×10-3, the luminescence intensity reached the summit. And there is a phenomenon of concentration quenching. Investigation with the same concentration of Eu3+ at different annealed temperature, we found that the sample annealed at 400 ℃, the luminescence intensity achieved its maximum value, and Eu3+ in this matrix had a phenomenon of temperature quenching. The structural characterization of these luminescent materials was carried by used XRD and TEM. The result showed that the phosphor was in amorphous phase.    

14.  Luminescence Kinetic Model for Long-Afterglow Phosphor (Sr0.5 Ca1.5 ) MgSi2O7 :Eu^2+ ,Dy^3+  
   刘波 施朝淑 陶冶 肖志国《中国物理快报》,2005年第22卷第5期
   A luminescence kinetic model for the green-emission long-afterglow phosphor (Sr0.5 Ca1.5)MgSi2O7:Eu^2 ,Dy^3 is proposed based on the studies of the thermoluminescence and isothermal decay curves at different temperatures.The isothermal decay curves at different temperatures meet the hyperbolic law and show to be dependent on temperature. Combined with the decay curves and the thermoluminescence curves, it can be concluded that the long afterglow of this material originates from the traps with energy distribution rather than a single level trap.Upon illumination with ultra-violet or visible light, the trap filling can proceed via excitation of 4f electrons to the 5d level of Eu^2 ions. After excitation, 5d electrons can be transferred to the trap related to Dy3 ions, and Eu^3 is left behind. Upon subsequent heating, the electron is released from this trap and recombines with Eu^3 to produce Eu^2 emission.    

15.  Improving luminescent property of SrIn2 O4 :Eu3+ by co-doped A+ (A = Li, Na, K) or Sm3+  
   王志军  李盼来  杨志平  郭庆林《中国物理 B》,2013年第4期
   A series of SrIn2 O4 :Eu3+ phosphors are synthesized by a high temperature solid-state method, and their luminescent properties are investigated. They can be excited by 395-nm radiation, and produce red emission (619 nm); however, they have a low absorption of near-ultraviolet light with the wavelength of 400nm-405 nm. When co-doped with A+ (A=Li, Na, K), the emission intensity of SrIn2O4 :Eu3+ is significantly enhanced, but its emission and excitation spectral profile is unchanged. With co-doping Sm3+ , not only is the emission intensity of SrIn2 O4 :Eu3+ enhanced, but also the absorption is broadened and strengthened in the range of 400 nm-405nm. The effect of Sm3+ -doped content on the emission intensity of SrIn2O4 :Eu3+ , Sm3+ is investigated, and the optimal Sm3+ content is 0.02 mol.    

16.  Luminescence characteristics of Eu2+ activated Ca2SiO4 Sr2SiO4 and Ba2SiO4 phosphorsfor white LEDs  
   王志军  杨志平  郭庆林  李盼来  傅广生《中国物理 B》,2009年第18卷第5期
   <正>This paper investigates the luminescence characteristics of Eu2+ activated Ca2SiO4,Sr2SiO4 and Ba2SiO4 phosphors. Two emission bands are assigned to the f-d transitions of Eu2+ ions doped into two different cation sites in host lattices,and show different emission colour variation caused by substituting M2+ cations for smaller cations.This behaviour is discussed in terms of two competing factors of the crystal field strength and covalence.These phosphors with maximum excitation of around 370 nm can be applied as a colour-tunable phosphor for light-emitting diodes(LEDs) based on ultraviolet chip/phosphor technology.    

17.  La2O2S∶Mn2+荧光粉的微波合成及其荧光特性  
   李其华  汪萍  曾立华  刘利民  廉世勋《无机化学学报》,2006年第22卷第2期
   Using La2(SO4)3 and the active carbon powder as reactants, La2O2S∶Mn2+ red phosphor was synthesized by microwave radiation method. The phosphor was characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), laser-diffraction size analyzer and fluorospectrophotometer. The XRD analysis showed that the phosphor was pure phase La2O2S. The phosphor of La2O2S∶Mn2+ showed hexagonal crystal structure with diverse shapes, such as spherical and rod, with average particle size of 10.22 μm. The emission and excitation spectra of the phosphor were determined by fluorospectrophotometer and the results showed that the excitation spectrum of the phosphor under 600 nm emission wavelength was excitation bands between 250 nm and 350 nm with a peak value of 303 nm. Then ,when exicited under UV 303 nm, the phosphor showed broad band emission of 550~700 nm with a peak at 607 nm. In addition, the optimal effects were obtained for the phosphor preparation when the concentration of the activator Mn2+ was xMn=0.01, the ratio of C and O (nC / nO) in the reactants was 0.6∶1, and the time of reaction was about 1 h. La2O2S∶Mn2+ has strong absorption of UV spectrum and can emit bright red light.    

18.  Long-Lasting Phosphorescence Properties of Pyrochlore La2Ti2O7:Pr^3+ Phosphor  
   褚明辉  蒋大鹏  赵成久  李斌《中国物理快报》,2010年第27卷第4期
   The La2Ti2O7:Pr^3+, which emits red color luminescence upon UV light excitation, is prepared by the conventional high-temperature solid-state method and its luminescent properties are systematically investigated. X-ray diffraction, photoluminescence, afterglow emission spectra and long-lasting phosphorescence (LLP) decay curves are used to characterize this phosphor. After irradiation by a 290-nm UV light for 3 rain, the Pr^3+-doped La2Ti2O7 phosphor emits intense red emitting afterglow from the ^1D2 →^ 3H4 transitions, and its afterglow can be seen with the naked eye in the dark clearly for more than 1 h after removal of the excitation source. The afterglow decay curve of the Pr^3+-doped La2Ti2O7 phosphor contains a fast decay component and another slow decay one. The possible mechanism of this red light emitting LLP phosphor is also discussed based on the experimental results.    

19.  溶剂热合成纳米球状La2O2S:Eu^3+荧光粉  
   邝金勇 刘应亮 张静娴 袁定胜《高等学校化学学报》,2005年第26卷第5期
   Nano-sphere-like Eu^3 activated lanthanum oxysulfide phosphor was first synthesized directly by solvothermal method. The phosphor was characterized by XRD, TEM and PL. Photoluminescence spectra indicate that this phosphor showed three typical transitions of Eu^3 (^5Do→^7F^1,^5D0→^7F2,^5D0→^7F4). In comparison with those prepared by high temperature solid state method, photoluminescence spectrum of Eu^3 (^5D0→^7F2)-doped nano-La2O2S:Eu^3 phosphor became broader. And the reaction mechanism was also mentioned in this paper.    

20.  Photoluminescence properties of Y0.75-xGdxAl0.10BO3:Eu0.103+,0.05R3+(R= Sc,Bi) (0.00 ≤ x ≤ 0.45)  
   李杰  王育华  董其铮  刘吉地《中国物理 B》,2010年第6期
   Y 0.75 -x Gd x Al 0.10 BO 3 :Eu0.10 3+, 0.05R 3+ (R=Sc, Bi) (0.00 ≤ x ≤ 0.45) powder samples are prepared by solid-state reaction and their luminescence properties are investigated. With the replacement of Y 3+ ions by Sc 3+ (or Bi 3+ ) and Gd 3+ ions in (Y,Al)BO 3 :Eu, the intensities of emission at 254 and 147 nm are remarkably improved, because Sc 3+ ions can absorb UV light and transfer the energy to Eu 3+ ions efficiently. Moreover, Gd 3+ and Bi 3+ ions act as an intermediate "bridge" between the sensitizer and the activator (Eu 3+ ) in energy transfer to produce light in the (Y, Gd)BO 3 :Bi 3+ , Eu 3+ system more effectively. After doping an appropriate concentration of Gd 3+ into Y 0.50 Gd 0.25 Al 0.10 BO 3 :Eu0.01 3+ , Bi0.05 3+ , the emission intensity reaches its maximum, which is nearly 110% compared with the red commercial phosphor (Y,Gd)BO 3 :Eu and better chromaticity coordinates (0.650, 0.350) are obtained.    

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