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1.
近年来由于等离子体平板显示 (PDP)技术的需要 ,对真空紫外 (VUV)光激发的荧光粉的研究成为发光材料领域中的一个新方向 [1~ 3] .由于技术和实验仪器等方面的原因 [4 ] ,以往人们对稀土发光材料VUV区的研究很少 ,缺乏对其光谱和能级的完整认识 .另外 ,稀土离子 Gd3+在荧光粉的能量传递中具有特殊作用 ,一些含 Gd3+的发光材料在 VUV区发光效率很高 ,例如 ,(Y,Gd) BO3∶ Eu在 VUV区的发光效率比 YBO3∶ Eu提高了 2 0 % ,比 Y2 O3∶ Eu提高了 1 .8倍 ,与其它红粉相比更具有实际应用价值 [4 ,5] .但目前对于 (Y,Gd) BO3∶ Eu的研…  相似文献   

2.
LaAl3(BO3)4的合成及其晶体结构的研究   总被引:1,自引:3,他引:1  
在研究LnAl3(BO3)(Ln=稀土元素,Y)的合成及发光特性过程中,发现镧铝硼酸盐LaAl3(BO3)4具有一种新的晶体结构。本文用助熔剂法合成了LnAl3(BO3)4(Ln=Gd,La)单晶样品,LaAl3(BO3)4为薄板状,而GdAl3(BO3)4为六方的棒状,用TREOR90程序对LaAl3(BO3)4粉末样品的X射线衍射数据进行了指标化,结果为:LaAl3(BO3)4属正交晶系,晶胞参数为a=0.93586(4)nm,b=0.79904(3)nm,c=0.40626(6)nm,V=0.34595nm^3,在1000℃空气环境下,用硝酸盐热分解法合成了单相LnAl3(BO3)4:E3 (Ln=Gd,La)荧光粉并研究了其发光特性,结果表明:LnAl3(BO3)4:Eu^3 (Ln=Gd,La)是非常有前途的等离子显示器用荧光粉。  相似文献   

3.
3-(3-吡啶基)丙烯酸(3-HPYA)配体与稀土金属离子钆(Gd)通过水热法合成了一种新的一维链状配位聚合物[Gd(3-HPYA)3(H2O)]n(1),其结构经IR,热重分析,元素分析和x-射衍单晶衍射仪表征.1属于三斜晶系,空间群P-1,晶胞参数为:a=0.61943(15)nm,b=1.27000(3)nm,c=1.563 40(4)nm,α=111.728(4)°,β=90.330(4)°,γ=95.202(4)°,Z=2.1通过分子间的氢键堆积为三维网状结构.对1的热稳定性进行了研究.  相似文献   

4.
1 INTRODUCTION At present the researches on more efficient solid-state laser materials become more important for the rapid development of diode-laser pumped solid-state laser. More researches have been devoted to the double borate compounds RX3(BO3)4 (R = Y, La, Gd and X = Y, Al, Sc), some of which exhibit good chemical and physical properties[1~10]. The rare earth and alkali-halide double borates M3Ln2(BO3)4 (M = Ca, Sr, Ba and Ln = LaLu and Y) were reported in literatures[11…  相似文献   

5.
1 INTRODUCTION In recent years, more and more attention has been paid to rare-earth borates due to their excellent pro- perties, such as YCa4O(BO3)3(YCOB)[1], YAl3(BO3)4 (YAB)[2] and La2CaB10O19[3] for nonlinear optical materials and self-frequency doubling materials as well as YBO3:Eu for red phosphor materials[4] and Li6M1-xCex(BO3)3 (M = Y, Gd) for neutron detec- tors[5]. In this work, we focus our research interest on LiY6O5(BO3)3 as hosts for VUV (vacuum ultraviolet) l…  相似文献   

6.
0引言在绿色和蓝色长余辉发光材料达到应用程度之后,耐候性红色长余辉发光材料成为人们研究的重点。Eu3 、Sm3 激活的硫氧化物[1 ̄3]、Eu2 铝锶复合硫氧化物[4]和Y2O3∶Eu3 [5]等耐热耐水性红色长余辉材料被相继发现。Pr3 离子掺杂的碱土金属钛酸盐(M TiO3∶Pr,M=M g,Ca,Sr,Ba)是一种新型的红色长余辉发光材料。这种发光材料在615nm附近有很好的单色性红光发射。碱土金属钛酸盐基质化学性能稳定,已开始应用于场发射显示器(FE D)[6,7]。碱土金属钛酸盐是A BO3型化合物,具有钙钛矿结构。B all[8]曾通过在CaTiO3中掺入不同量的Sr2 …  相似文献   

7.
Ca3Al2Ge3O12:Cr3+的光谱性质及晶场参数计算   总被引:1,自引:0,他引:1  
为了解Cr3 离子在钙铝锗酸盐Ca3Al2Ge3O12石榴石中的光谱性质,合成了Ca3Al2Ge3O12:Cr3 多晶材料;测量了其X射线衍射图,漫反射光谱,激发、发射光谱等;分析了Cr3 离子在钙铝锗酸盐中的发光特性;计算了其晶场强度(Dq/B),Stokes位移(ΔEs)及黄昆-里斯因子(S)等.在450nm激发下,Ca3Al2Ge3O12:Cr3 室温发射光谱主要由三个宽带及附加其上的弱R线构成,分别对应于Cr3 离子的4T1、4T2、2T2到4A2能级跃迁.低温时R线变得强而锐.通过计算,Dq/B=2.43,ΔEs=1884cm-1,S=5.21.表明在Ca3Al2Ge3O12中Cr3 离子处于较弱的晶场强度,电子-声子耦合较强,为发展可调谐激光材料提供重要线索.  相似文献   

8.
以三聚氰胺和硼酸为原料在水溶液中反应合成出了一种新的BCN化合物先驱体C3N6H6(H3BO3)2。XRD表征结果表明三聚氰胺和硼酸的最佳配比为1∶3(物质的量比)。用单晶X-射线衍射分析法测定了该化合物的晶体结构。该化合物属单斜晶系,空间群为P21/C,晶胞参数为a=0.3597(7)nm,b=2.0105(4)nm,c=1.4112(3)nm,α=90,°β=92.07(3),°γ=90,°V=1.0199(3)nm3,Z=4,D c=1.627g.cm-3,μ(MoKα)=0.144mm-1,F(000)=520。晶体结构经全矩阵最小二乘法修正,最终可靠因子R1=0.0519,wR2=0.1361。该化合物是由C3N6H6分子和H3BO3分子通过氢键加合组装形成的三维超分子结构化合物。  相似文献   

9.
报道了新型配合物(NH4)3[Dy(TTHA)]*5H2O(TTHA=三乙四胺六乙酸)的分子结构和晶体结构. 配合物晶体参数为 单斜晶系, P2(1)/c空间群, a=1.0353(3) nm, b=1.2746(4) nm, c=2.3141(7) nm, β=91.005(5)°, V=3.053(15 nm3), Z=4, M=795.10, Dc=1.730 g*cm-3, μ= 2.532 mm-1, F(000)=1620. 其R和Rw值分别为0.0332和0.0924(对5390个独立的衍射点), R和Rw值分别为0.0460和0.1012(对所有12395个衍射点). 配合物(NH4)3[Dy(TTHA)]*5H2O中的[Dy(TTHA)]3- 部分是一个九配位的非标准单帽四方反棱柱体结构. 十齿TTHA配体提供四个胺基氮原子和五个羧基氧原子与中心金属Dy(Ⅲ)离子配位. 为使[Dy(TTHA)]3-部分在体内具定向功能, 结构中未参与配位的自由羧酸基(-CH2COO-)可采用某些生物分子修饰.  相似文献   

10.
通过三(邻甲苯基)氢化锡与1-乙炔基环己醇和1-乙炔基环戊醇发生加成反应,得到两个加成物:(Z)-1-[2-(三-邻甲苯基锡基)乙烯基]环戊醇(1)和(Z)-1-[2-(三-邻甲苯基锡基)乙烯基]环己醇(2).通过元素分析、红外光谱和核磁共振氢谱等手段对其结构进行了表征.用X射线单晶衍射测定了加成物1和2的晶体结构.二者均为具有分子内O→Sn弱配位的扭曲四面体结构.1属于单斜晶系,P21/n空间群,晶胞参数:a=1.0496(2)nm,b=1.7658(4)nm,c=1.3193(3)nm,β=90.60(3)°,V=2.4451(8)nm3,Z=4,R=0.0317,wR=0.0820.2属于三斜晶系,空间群P1,晶胞参数:a=O.85592(17)nm,b=0.93016(19)nm,c=1.6368(3)nm;α=83.76(3)°,β=82.69(3)°,γ=78.05(3)°;V=12600(4)nm3,Z=2,R=0.0377,wR=O.1030.  相似文献   

11.
配合物EuxM1-x(TTA)3(H2O)2(M=La,Gd)光致发光特性   总被引:13,自引:0,他引:13  
合成了一系列组成为EuxM1-x(TTA)3(H2O)2(M=La,Gd)的固体配合物,利用红外光谱和荧光光谱研究了配合物结构和发光性质随Eu3+浓度的变化规律.红外光谱的结果表明,配合物的成份为Eu(TTA)3(H2O)2和M(TTA)3(H2O)2,没有新化合物生成.而荧光光谱的结果显示配合物的发光强度与Eu3+浓度不成线性关系,其中不发光的M(TTA)3组分对发光有增益作用.对其可能的发光机制进行了探讨.  相似文献   

12.
Spectral properties of Gd3+, Dy3+ and Eu3+ ions in SrGdAlO4 are reported in detail. A cooperative vibronic transition of Gd3+ and the emission from the higher 5DJ (J=1, 2, 3) levels of Eu3+ were observed. Energy transfer occurs from Gd3+ to Dy3+ and to Eu3+. The influence of Gd3+ and Dy3+ concentrations on the luminescence intensity is discussed.  相似文献   

13.
Eu(TTA)_3/MCM-41介孔复合体的溶胶凝胶法组装   总被引:2,自引:1,他引:1  
利用溶胶 凝胶法将稀土配合物Eu(TTA) 3 组装到MCM 41介孔分子筛的孔道中 ,并初步认定客体分子Eu(TTA) 3 是以加合物形式包裹于表面活性剂胶束中。该法制得的介孔复合体Eu(TTA) 3/MCM 41,用XRD、HRTEM技术证实具有短程有序的、规整的六方介孔结构和大小分布均匀的纳米晶粒。对其光致发光和荧光寿命的研究发现 :与乙醇溶液中相比 ,Eu3 的荧光寿命没有发生改变 ,但Stokes位移却明显增大 ;复合体中 ,能量是从主体MCM 41传递到客体Eu(TTA) 3 上。  相似文献   

14.
以尿素为燃烧剂,乙二醇为分散剂采用燃烧法制备了Gd3Ga5O12∶Eu3+纳米晶。利用X射线衍射、电镜和荧光光谱对前驱体和热处理后样品的结构、形貌和发光性能进行了表征。XRD结果表明:700℃热处理2 h即可获得立方结构Gd3Ga5O12∶Eu3+纳米晶。根据Scherrer公式估算经700℃和900℃热处理2 h获得的纳米晶的一次性粒径分别为28 nm和42 nm。发射光谱和激发光谱的结果表明:特征发射峰来自于5D0-7FJ跃迁,而来自于Eu3+的5D0→7F1的磁偶极跃迁发射最强;宽激发带主要来自于Eu-O电荷迁移带和Gd3Ga5O12基质吸收。发射强度和激发强度随热处理温度的提高而增强。  相似文献   

15.
The colloids of Eu(DBM)3 and ultrafine particles Eu(DBM)3 were perpared. The particle sizes determined by X-ray and by TEM measurements were in 7-30nm range. Their UV absorption and fluorescence spectra were compared with each other and with those of the solid sample. It was shown that the 5D1→7 F1,2 transition was observed in the colloids of Eu(DBM)3 at room temperature. The increase of the excited-state S1 and T1 energy, the peak positions of UV absorption shifted to shorter wavelength, the changes of the absoprtion coefficient with decreasing size were observed.  相似文献   

16.
<正>This paper reports the growth,X-ray diffraction and spectroscopy of Nd~(3+):Sr_3Gd_2(BO_3)_4 crystal.A Nd~(3+):Sr_3Gd_2(BO_3)_4 crystal with dimensions ofφ20×45 mm~3 has been grown by the Czochralski method.Nd~(3+):Sr_3Gd_2(BO_3)_4 crystal belongs to the orthorhombic system,space group Pnma(D_(2h))with a=0.7401,b=1.604 and c=0.8755 nm.The absorption and emission spectra of Nd~(3+):Sr_3Gd_2(BO_3)_4 were investigated.The absorption cross sectionσ_a is 3.11×10~(-20)cm~2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm.The luminescence lifetimeτ_f is 51.7 us.The emission cross sectionσ_e at 1064 nm wavelength is 1.09×10~(-19)cm~2.  相似文献   

17.
As an Hg-free lamp using phosphor,the Bi3+ and Eu3+ co-doped Y2O2S phosphors were prepared and their luminescence properties under vacuum uitraviolet(VUV) excitation were investigated.The VUV photolumineseent intensity of Y2O2S:Eu3+ was weak,however,considerably stronger red emission at 626 nm with good color purity was observed in Y2O2S:Eu3+,Bi3+ systems.Investigation on the photoluminescence reveals that the strong VUV luminescence of Y2O2S:Eu3+,Bi3+ at 147 nm is mainly because the Bi3+ acts as a medium and effectively performs the energy transfer process: Y3+-O2→Bi3+→Eu3+,while the intense emission band at 172 nm is attributed to the absorption of the characteristic 1So-1P1 transition of Bi3+ and the direct energy transfer from Bi3+ to Eu3+.The Y2O2S:Eu3+,Bi3+ shows excellent VUV optical properties compared with the commercial (Y,Gd)BO3:Eu3+.Thus,the Y2O2S:Eu3+,Bi3+ can be a potential red VUV-excited candidate applied in Hg-free lamps for backlight of liquid crystal display.  相似文献   

18.
Ca3La3(BO3)5中Eu3+的光致发光   总被引:2,自引:0,他引:2  
本文详细地研究了紫外光激发下,Ca_3La_3(BO_3)_5中Eu~(3+)的发光光谱和激发光谱与组成、结构的关系.发现Eu~(3+)在此基质中可能不止一个发光中心;Eu~(3+)自身浓度猝灭的机理为电四极-四极相互作用.  相似文献   

19.
As an Hg-free lamp using phosphor, the Bi3+ and Eu3+ co-doped Y2O2S phosphors were prepared and their luminescence properties under vacuum ultraviolet(VUV) excitation were investigated. The VUV photoluminescent intensity of Y2O2S:Eu3+ was weak, however, considerably stronger red emission at 626 nm with good color purity was observed in Y2O2S:Eu3+,Bi3+ systems. Investigation on the photoluminescence reveals that the strong VUV luminescence of Y2O2S:Eu3+,Bi3+ at 147 nm is mainly because the Bi3+ acts as a med...  相似文献   

20.
Luminescence accompanying an impact mechanical treatment of solid particles of the complex of Eu(fod)3 (fod is 1,1,1,2,2,3,3-heptafluoro-7,7-dimethyloctane-4,6-dione) with dispiro(adamantane-1,2-dioxetane) (1) was discovered and studied. The luminescence has a complex structure, and its spectrum belongs to the excited EuIII ions. The emission of light is observed only in a mechanical mixture of the Eu(fod)3 with dioxetane1 and in their cocrystallized form, but not in the case of the components taken separately. The mechanism by which the impacts cause the luminescence is considered. It was shown that the luminescence is not triboluminescence, but is chemiluminescence induced by the decomposition of compound1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1159–1162, May, 1996.  相似文献   

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