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Yb3+∕Er3+∕Tm3+ tri-doped phosphate glass ceramics were prepared by a high-temperature melting method and thermal treatment technology. Upconversion (UC) emissions of the Yb3+∕Er3+∕Tm3+ tri-doped phosphate glass ceramic samples were studied under 975 nm excitation. The glass ceramic samples can simultaneously generate blue, green, and red emissions. The multicolor emission obtained was tuned to white light by adjusting the Er3+ ion concentration. The emission color of the sample doped with 8 mol.% Er3+ ion is white to the naked eye, and CIE coordinates (x=0.316, y=0.354) of the sample are close to the standard equal energy white-light illumination (x=0.333, y=0.333). The material will be useful in developing the white-light-emitting diode. 相似文献
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Gd3+为敏化剂的掺Tb3+硅酸盐闪烁玻璃 总被引:2,自引:0,他引:2
实验制备了以Tb3+为激活剂、Gd3+为敏化剂的硅酸盐闪烁玻璃, 研究了Tb2O3和Gd2O3含量对玻璃密度和玻璃折射率, 以及对玻璃在紫外光激发和X射线激发条件下的光学光谱特性的影响. 通过研究Tb3+/Gd3+共掺闪烁玻璃的激发与发光特性、荧光寿命, 结合稀土离子能级结构, 分析了Gd3+→Tb3+离子之间的能量转移与传递机制. 结果表明:在紫外激发条件下, 大量引入Tb2O3和Gd2O3可提高Gd3+→Tb3+离子之间的能量传递效率, 有利于Tb3+离子的绿色发光; 但是在X射线激发条件下大量引入Tb3+离子, 由于缺陷数增加而弱化Tb3+离子荧光. 相似文献
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以菱镁矿风化石、工业Al2O3和SiO2微粉为原料,固相反应烧结合成制备堇青石.通过在反应物中分别加入不同含量的Eu2O3、Dy2O3和Er2O3,研究分析和对比了Eu3+、Dy3+和Er3+对堇青石晶相组成、晶粒大小、晶胞常数、结晶度及显微结构的影响.采用XRD和SEM表征试样中的晶相和显微结构,利用X'Pert Plus 软件对结晶相的晶胞参数和结晶度进行分析,采用半定量法对试样晶相组成进行计算,利用Scherrer公式计算堇青石的晶粒大小.结果表明:由于Eu2O3、Dy2O3和Er2O3的加入,通过固相反应烧结所得堇青石试样中出现了莫来石相,Eu3+、Dy3+和Er3+对Mg2+的置换作用改变了堇青石相晶格常数和晶胞体积.随着添加剂含量的增加,堇青石结构中液相量增加,相对结晶度降低,常温致密度提高,堇青石晶粒粒径减小.综合对比分析,Eu2O3对堇青石晶相转变的影响程度最弱,Er2O3对堇青石晶相转变的影响程度最强,对提高合成堇青石的烧结性和热震稳定性效果最好. 相似文献
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采用溶胶-凝胶法制备了纯TiO2和Eu3+/Sm3+共掺杂TiO2复合粉体,采用XRD,DRS和SEM等技术进行表征,以亚甲基蓝(methylene blue,MB)的光催化降解为目标反应,评价了其光催化活性,探讨了Eu3+/Sm3+共掺杂对TiO2粉体光催化的影响机制.结果表明,Eu3+/Sm3+共掺杂可以显著提高TiO2粉体光催化活性,Eu3+/Sm3+共掺杂在TiO2粉体中产生协同作用,可以抑制TiO2由锐钛矿相向金红石相转变,使TiO2的粒径减小.Eu3+/Sm3+共掺杂增大了TiO2粉体的晶格畸变,使TiO2粉体吸收带边蓝移.当Eu3+/Sm3+的掺杂量分别为0.05%和0.1%,TiO2光催化活性最高,光催化降解率达到84.8%. 相似文献
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将BiGaO3和BiInO3分别引入BiScO3-PbTiO3(BSPT)体系,并通过氧化物合成法制备了0.075BiGaO3-(0.925-x)BiScO3-xPbTiO3(SPTx, x=0.58~0.62)和0.075BiInO3-(0.925-x)BiScO3-xPbTiO3(BISPTx, x=0.61~0.65)压电陶瓷.X射线衍射分析表明,BiGaO3和BiInO3的替换掺杂均不影响BSPT体系的钙钛矿结构.随着PbTiO3含量的增加,SPTx和BISPTx陶瓷由三方钙钛矿结构逐渐变到四方结构,其三方-四方准同型相界分别位于x=0.60和x=0.62附近.在准同型相界附近,SPTx陶瓷的压电常数d33,机电耦合系数kp为分别为350pC/N和52.0%,而BISPTx的d33高达475pC/N,kp为52.3%.介电常数的温度特性测试表明,掺入Ga3+可以有效地提升BSPT体系的居里温度,其MPB组分(x=0.60)居里温度高达472℃,而掺入In3+对BSPT体系的居里温度影响则不明显. 相似文献
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Gd3+-Tb3+能量转移与Tb3+自敏化效应对重金属锗酸盐玻璃发光性能的影响 总被引:3,自引:0,他引:3
研究了一组Tb^3 掺杂重金属锗酸盐玻璃的发光特性。玻璃样品的X射线激发发射光谱结果显示,玻璃基质中由Gd^3 离子向发光中心Tb^3 的能量转移机制以及在一定浓度范围内Tb^3 之间的交叉弛豫过程对玻璃的发光性能有重要影响。前者表现在Gd^3 紫外发射光的减弱及Tb^3 绿发射光的增强,后者则显示Tb^3 在一定浓度范围内所特有的自敏化效应,使其蓝发射光减弱、绿发射光增强。第3种稀土离子La^3 的引入对发光中心Tb^3 离子具有分离效应,使Tb^3 之间的交叉弛豫概率降低,蓝发射光增强。 相似文献
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Pr3+摩尔浓度对CaTiO3:Pr3+红色长余辉材料的影响 总被引:7,自引:0,他引:7
制备了不同Pr^3 摩尔浓度下的CaTiOs:Pr^3 红色长余辉材料,测量了磷光体的的初始亮度、余辉曲线、激发光谱和发射光谱、热释光曲线。研究发现CaTiO3:Pr^3 合适的Pr^3 摩尔浓度为0.1%—0.2%,在该摩尔浓度下,材料具有较好初始亮度和余辉时间。 相似文献
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Cao Renping Liu Na Zhong Qinghu Tu Yafang Xu Yongchun Zhang Haining Luo Wei Chen Ting 《Journal of Materials Science: Materials in Electronics》2021,32(22):26620-26630
Journal of Materials Science: Materials in Electronics - In this work, Ca3MgSi2O8:Bi3+, Ca3MgSi2O8:xEu3+ (x?=?0, 2, 4, 6, 8, and 10 mol%), and Ca3MgSi2O8:6%Eu3+, yBi3+... 相似文献
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Qingling Kong Jinxian Wang Xiangting Dong Wensheng Yu Guixia Liu 《Journal of Materials Science》2014,49(7):2919-2931
LaOCl:Yb3+, Er3+ nanofibers and hollow nanofibers were prepared by electrospinning combined with a double-crucible chlorination technique using NH4Cl as chlorinating agent. X-ray powder diffraction analysis indicated that LaOCl:Yb3+, Er3+ nanostructures were tetragonal with space group P4/nmm. Scanning electron microscope analysis and histograms revealed that diameters of LaOCl:Yb3+, Er3+ nanofibers and hollow nanofibers, respectively, were 117.87 ± 15.48 and 141.09 ± 17.10 nm under the 95 % confidence level. Up-conversion (UC) emission spectra analysis manifested that LaOCl:Yb3+, Er3+ nanostructures exhibited strong green and red UC emission centering at 526, 548, and 671 nm, respectively, attributed to 2H11/2 → 4I15/2, 4S3/2 → 4I15/2, and 4F9/2 → 4Il5/2 transitions of Er3+ ions under the excitation of a 980-nm diode laser. It was found that the relative intensities of green and red emissions vary obviously with the addition of Yb3+ ions, and the optimized molar ratio of Yb3+ to Er3+ was 10:1 in the as-prepared nanofibers. Moreover, the near-infrared characteristic emissions of LaOCl:Yb3+, Er3+ nanostructures were achieved under the excitation of a 532-nm laser. CIE analysis demonstrated that color-tuned luminescence can be obtained by changing doping concentration of Yb3+ (and/or Er3+) ions and morphologies of nanomaterials, which could be applied in the fields of optical telecommunication and optoelectronic devices. The UC luminescent mechanism and the formation mechanisms of LaOCl:Yb3+, Er3+ nanofibers and hollow nanofibers were also proposed. 相似文献
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按照零场分裂(ZFS)的三阶微扰理论和叠加晶场模型,建立了ZFS参量D与CsCdF3:Cr3+晶格结构之间的定量关系;同时考虑了晶格畸变和Cd2+空位对零场分裂参量D的贡献,计算了CsCdF3:Cr3+晶体的零场分裂参量D,计算结果与实验符合甚好.证明了晶格畸变和Cd2+空位的存在;同时得到包围 Cr3+离子的 F-离子向中心 Cr3+离子分别移动X1=0.00291nm,X2=0.001nm,X3=0.0026nm.CsCdF3:Cr3+晶体基态的ZFS主要来自Cd2+空位,但晶格畸变的贡献是不能忽略的. 相似文献
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《Optical Materials》2014,36(12):2138-2145
Dy3+ and Tm3+ co-doped YAl3(BO3)4 (YAB) phosphors were prepared by solid-state reaction method at 1200 °C/3 h. The average crystallite size was determined as 52.09 nm from the X-ray diffraction measurements. Upon 352 and 359 nm near ultra violet excitation, the YAB:Dy3+–Tm3+ phosphors exhibit Dy3+:4F9/2 → 6HJ (J = 15/2, 13/2, 11/2) and Tm3+:1D2 → 3F4 transitions with different luminescence intensity. The photoluminescence emission and decay measurements revealed the energy transfer from Dy3+ to Tm3+ ions under 359 nm excitation only. The energy transfer between Dy3+ and Tm3+ takes place in Dy3+–Tm3+ clusters through exchange interaction mechanism. The Commission International de I’Eclairage chromaticity coordinates of YAB:Tm3+ phosphor (λex = 359 nm) were found very close to the European Broadcasting Union and National Television Standard Committee illuminants. The emission color of the studied phosphors could be tuned from blue-to-white as a function of excitation wavelength. The YAB:Dy3+–Tm3+ phosphors can be used as potential candidates in display technology. 相似文献
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Pr3+掺杂对SrAl2O4:Eu2+、Dy3+磷光体发光性能的影响 总被引:1,自引:0,他引:1
用燃烧法制备Pr~(3+)掺杂的SrAl_2O_4:Eu~(2+)、Dy~(3+)长余辉发光粉体,研究了Pr~(3+)掺杂对其发光性能的影响。结果表明,合成的单相SrAl_2O_4样品具有单斜晶系结构,荧光发射光谱是连续宽带谱,峰位于515 nm,激发光谱是峰值在320 nm和360 nm的连续宽带谱。掺杂Pr~(3+)对形成晶粒尺寸均匀的固溶体有一定的促进作用,使其余辉初始亮度为不掺杂时的3倍。 相似文献
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In3+Nb5+双取代钙钛矿型锂快离子导体Li3xLa0.67-xTiO3的研究 总被引:1,自引:0,他引:1
以Li3xLa0.67-xTiO3为母体,通过掺杂经高温固相反应制得了一系列新的锂快离子导体材料Li3xLa0.67-xInyTi1-2yNbyO3.利用X射线衍射分析和交流阻抗技术研究该系统的组成结构和电化学性能.结果表明体系合成温度降低,分解电压提高了;在x=0.10,y<0.050时,合成物为单一的钙钛矿固溶体,y≥0.050时,则存在In2O3杂相;该体系合成物在室温下有较高的电导率,可达5.81×10-4S/cm,活化能在20~30kJ/mol之间. 相似文献
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《Optical Materials》2013,35(12):2050-2054
Multicomponent telluride-tungstate glasses containing Nd3+ and Er3+ ions were studied experimentally at 77 and 293 K using spectroscopic methods. The Judd–Ofelt intensity parameters were derived from the absorption spectra and used to calculate the radiative lifetimes and branching ratios. The quantum efficiency η = 0.95 of the 4F3/2 level of Nd3+ ion is higher than the typical value of other tellurite-based glasses. For low concentration of Er3+ ions, the luminescence decay of the 4S3/2 and 4I11/2 levels is governed by radiative transitions and multiphonon relaxation involving the Te-O highest energy vibrations. 相似文献