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Pr3+and Yb3+co-doped phosphate glasses are prepared to study their optical properties.Excitation and emission spectra and decay curves are used to characterize their luminescence.We demonstrate that upon excitation of Pr3+ion with one high energy photon at 470 nm,two near-infrared(NIR)photons are emitted at 950-1100 nm(Yb3+:2F 5/2 →2F 7/2)through an efficient cooperative energy transfer(CET)from Pr3+to Yb3+.The maximum energy transfer efficiency(ETE)and the corresponding quantum efficiency approach up to 90.17%and 190.17%,respectively.The glass materials might find potential application for improving the efficiency of silicon-based solar cells. 相似文献
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Co2+,Zn2+双掺杂铌酸锂晶体的坩埚下降法生长及其光谱特性 总被引:1,自引:0,他引:1
在LiNbO3中掺入0.1%(摩尔分数.下同)的CoO与3%,6%的ZnO,采用坩埚下降法技术生长了双掺杂的Co^2+:Zn^2+:LiNbO3晶体。用X射线衍射与差热分析表征了获得的晶体。测定了晶体不同部位在350~2500nm波段的吸收光谱。研究表明:Co离子位于LiNbO3晶体的崎变的氧八面体中,呈现+2价,沿着生长方向Co^2+在晶体中的浓度逐渐减少。ZnO的掺杂有效地抑制了Co^2+离子在晶体中的掺入,使得Co^2+在晶体中浓度的分布变得均匀。同时发现:ZnO的掺入使得上部晶体的熔点升高。从化学组分的角度解释了产生熔点变化的原因。观测到了750nm波长的荧光发射带。[编者按] 相似文献
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微晶玻璃的制备与光谱特性 总被引:1,自引:0,他引:1
高温熔制摩尔组分为32CaO-12Y2O3-24Al2O3-31SiO2-1Yb2O3的玻璃, 制得的玻璃于950、1050、1100℃三个不同温度进行热处理, 用XRD分析热处理后样品的相变, 用TEM观察1050℃热处理后的样品, 并研究了1050℃热处理前后样品的光谱特性. 研究结果表明: 玻璃在1050℃热处理后, 在玻璃中产生单一YAG相微晶颗粒; 热处理前后样品光谱特性的变化表明热处理后掺杂的Yb 3+离子择优进入到YAG晶格位, 制备得到了透明Yb:YAG微晶玻璃. 相似文献
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用光刻、软刻和氧化硅球晶体模板制备表面微结构 总被引:1,自引:0,他引:1
表面微结构的制备对获得超疏水性表面和改善生物医学材料性能具有重要意义. 为了制备微米、亚微米和纳米级表面微结构, 本文采用光刻(photo-lithography)和软刻技术(soft lithography) 制备了微米尺寸长方体或圆柱体的阵列, 压印出变形长方体(塔状)或圆柱体(圆盘状)阵列的微结构表面; 采用单分散氧化硅球自集聚紧密堆积而成的胶体晶体为模板, 制备了亚微米/纳米 尺寸网状微结构的表面. 用光学和扫描电子显微镜表征了所获得的表面微结构. 相似文献
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将手性分子葡萄糖(glucose,C6H12O6)与灰黄霉素(griseofulvin,C17H17ClO6)掺入到溶胶-凝胶固体材料中,研究了复合材料的极化特性、吸收光谱与热稳定性.差热分析(DTA)结果表明掺杂于凝胶中的C6H12O6与C17H17ClO6分子在空气环境下,分别在210℃与350℃温度以下时,能够稳定存在.在红外光谱中,观测到由OH离子吸收引起的1.4 μm的吸收带.掺杂于固体介质中的手性分子保持了在溶液中的旋光性质.C6H12O6与C17H17ClO6分子在凝胶中的旋光率分别为-0.95°/cm与-1.45°/cm,技术所得的手征参数分别为1.55×10-7与2.37×10-7. 相似文献
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测量了不同掺杂浓度下掺Yb3+硼酸盐玻璃的吸收光谱、荧光光谱和上转换光谱.研究了Yb3+掺杂浓度对其发光强度、荧光寿命和上转换发光的影响及浓度猝灭机理.实验结果表明Yb3+离子掺杂浓度到1 atm%时,Yb3+离子的荧光强度开始下降,出现浓度猝灭效应,Yb3+硼酸盐玻璃的浓度猝灭主要是杂质稀土离子引起的.Yb3+掺杂硼酸盐玻璃中能量从Yb3+离子向杂质稀土离子的能量转移,使Yb3+产生浓度猝灭效应. 相似文献
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The transparent oxyfluoride glass ceramics containing Ba Gd F5 nanocrystals were prepared with a composition of 42 Si O2-12Na2O-16Al2O3-24 Ba F2-4Gd2O3-2Ce F3(mol.%) by thermal treatment technology. The typical DSC curve, X-ray diffraction(XRD) and transmission electron microscopy(TEM) patterns were measured. The transmission spectra and luminescent properties were investigated. The decay times of the Gd3+ ions at 312 nm excited with 275 nm for the Ce3+ ions doped glass and glass ceramics specimens and the energy transfer process between Gd3+ ions and Ce3+ ions were also studied. The XRD analysis and the TEM images confirmed the generation of the spherical Ba Gd F5 nanocrystals. Compared with the PG specimen, the intensity of the luminescence spectra of the glass ceramics specimens was apparently enhanced with the heat treatment temperature increasing, and a blue shift in the excitation spectra and the emission spectra of glass ceramics specimens was obviously observed. In the fluorescence decay curves of the Gd3+ ions, it could be obviously observed that the fluorescent intensity decays in the Ce3+ ions doped glass and glass ceramics specimens decreased rapidly with the increase of the heat treatment temperature. In addition, the energy transfer efficiency from Gd3+ions to Ce3+ ions was also calculated. 相似文献