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1.
Eu3+离子在微晶玻璃研究中的探针作用   总被引:3,自引:0,他引:3       下载免费PDF全文
制备出单掺Eu3+离子的氟氧化物玻璃陶瓷系列样品,利用Eu3+离子作为荧光探针,通过热处理前后Eu3+离子发射光谱中电偶极子跃迁与磁偶极子跃迁强度比值的变化表征在玻璃材料中微晶是否形成,分析了Eu3+离子荧光发射谱中电偶极子跃迁与晶体场对称性的关系,进一步表征了稀土离子所处微晶晶格场的变化.  相似文献   

2.
Er,Yb:YAG微晶玻璃发光特性的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
高温熔制Er3+,Yb3+离子掺杂CaO-Y2O3-Al2O3-SiO2系统玻璃,并进行微晶化处理,研究了微晶玻璃中Er3+离子的发光及上转换发光特性,分析了微晶玻璃上转换发光机理.结果表明:原始玻璃经热处理得到了Er,Yb:YAG微晶玻璃,微晶玻璃中Er3+离子在室温下4I13/24I15/2跃迁产生横盖1450—1650nm区间的超宽带荧光,荧光半高宽达180nm,这可能由于YAG微晶相中Er3+离子与玻璃相中残留Er3+离子的共同发光;Er3+与Yb3+离子局域基质声子能量的降低使微晶玻璃Er3+离子上转换发光强度与原始玻璃相比显著提高,绿光、红光上转换荧光强度比玻璃样品分别增强约7和3倍;微晶化后Er3+,Yb3+离子局域环境发生变化也导致微晶玻璃中Er3+离子绿光、红光上转换发光相对强度发生变化. 关键词: 铒 镱:钇铝石榴石 微晶玻璃 荧光光谱  相似文献   

3.
采用高温溶剂热法合成了下转换发光材料NaYF4∶Eu3+ 和NaYF4∶Eu3+,Tb3+ ,采用X射线衍射(XRD)、场发射扫描电镜(FESEM)、激发(PLE)谱和光致发光(PL)谱对材料的物相结构、形貌特征和发光性质进行了表征和研究,并分析了其发光原理。结果表明:所合成的NaYF4∶Eu3+ 和NaYF4∶Eu3+,Tb3+ 为纯六方相晶体,尺寸在100 nm左右;改变Eu3+ 和Tb3+ 的掺杂浓度后晶格结构没有发生明显变化,说明Eu3+ 和Tb3+ 取代的是Y3+的晶格位置;在394 nm光的激发下,检测到Eu3+5D07F15D07F2跃迁处的特征发射光,并且可见光强度随着Eu3+ 离子掺杂浓度的变化而变化。另外Tb3+ 离子浓度对NaYF4∶Eu3+ 晶体结构产生了一定的影响,说明掺杂Tb3+ 离子改变了Eu3+ 离子所处的配位环境,导致红色发光带增强,而这主要源于电偶极子跃迁的贡献。  相似文献   

4.
采用高温熔融法制备了一系列Ce3+/Sm3+共掺透明微晶玻璃,并研究了其发光特性。在微晶玻璃中Ce3+呈现出基于4f-5d跃迁的较强的宽带蓝光发射,通过调节Ce3+/Sm3+离子的掺杂浓度,Ce3+/Sm3+离子共掺微晶玻璃发光的色度逐渐发生变化,当CeO2/Sm2O3掺杂的量比为1:1时,制得的微晶玻璃发光色坐标为(0.315, 0.296)。通过光谱和荧光衰减曲线,研究了Ce3+离子到Sm3+离子的能量传递,在SAZKNGC0.6S0.6微晶玻璃中,Ce3+离子向Sm3+离子传递能量效率约为20%。结果表明,Ce3+/Sm3+共掺微晶玻璃是白光LED的一种潜在基质材料。  相似文献   

5.
采用熔体冷却法,通过控制玻璃基质组成及稀土离子添加量,制备了Tb、Eu单掺和Tb/Eu共掺的锌硼磷酸盐低熔点发光玻璃。测试了样品的红外光谱、吸收光谱、激发与发射光谱和荧光寿命,并计算CIE色坐标,研究了材料的微观结构及发光性能。结果表明:样品中部分Eu3+被还原为Eu2+,在380 nm波长激发下,Tb/Eu共掺发光玻璃同时出现Eu3+红光、Tb3+绿光和Eu2+蓝光的特征发射。增加基体中B2O3含量能强化玻璃网络结构,并改变Eu2+/Eu3+比例。发射光谱和荧光寿命测试表明,共掺的发光玻璃中存在Eu2+→Eu3+,Eu2+→Tb3+和Tb3+→Eu3+的能量传递。改变Tb、Eu的掺杂浓度能够有效改变发光玻璃的发光强度和颜色,最终得到色坐标为(0.318 7,0.286 1)、色温6 480 K的发光玻璃。  相似文献   

6.
孙家跃  曹纯  杜海燕 《物理学报》2011,60(12):127801-127801
采用水热法合成了不同粒径的NaLa(MoO4)2∶Eu3+微晶.通过调节乙二醇浓度和反应时间,研究了NaLa(MoO4)2∶Eu3+微晶的形貌演变过程,在水热条件下180 ℃反应16 h获得了均一梭子形NaLa(MoO4)2∶Eu3+微晶,其晶粒长度约为2.0 μm.荧光光谱分析表明,Eu3+取代了NaLa(MoO4)2中La3+的格位, Eu3+在613 nm处红光发射(5D07F2跃迁)的浓度猝灭机理是电偶极-电四极相互作用,并发生了Eu3+( 5D1 ) + Eu3+(7F0 )→ Eu3+( 5D0 ) + Eu3+(7F3) 交叉弛豫,由此导致浓度猝灭. 关键词: 钼酸盐 水热法 稀土离子 发光  相似文献   

7.
沈应龙  唐春梅  盛秋春  刘双  李文涛  王龙飞  陈丹平 《物理学报》2013,62(11):117803-117803
在还原气氛下, 采用高温熔融法制备了Eu2+/Ce3+共掺的高钆氧化物玻璃. 荧光性能测试显示, Ce3+能够有效地敏化Eu2+的发光, 使Eu2+的发光强度增强了2.3倍; 测试对比了Ce3+ 发光的荧光寿命随Eu2+的掺入前后的变化情况, 计算得出Ce3+→Eu2+ 的能量传递效率可达61.5%, 并进一步探讨了其能量传递机理. 研究表明: 在高钆氧化物玻璃中, 采用Eu2+ 和Ce3+ 共掺的方法可有效地增强Eu2+ 的发光性能和闪烁性能. 关键词: 发光玻璃 能量传递 荧光寿命  相似文献   

8.
研究了2.45 GHz微波灼烧(Ba,Sr)3MgSi2O8:Eu2+,Mn2+荧光粉的非热效应对Mn2+离子660 nm红光发射强度的影响。在相同的加热温度条件下,增加微波场的输出功率,微波非热效应导致Eu2+离子蓝光的跃迁概率增加,Eu2+通过(Ba,Sr)3MgSi2O8基质晶格把能量传递给Mn2+,进而使Mn2+的跃迁概率增加,导致红光发射增强。提出了一种微波场非热效应对能量传递影响的新观点,认为在微波加热过程中强微波磁场可能会对像Mn2+这样具有顺磁性的激活剂离子的能级结构和能量传递性质产生干扰作用。  相似文献   

9.
马晶  赵婉男  李艳红 《发光学报》2018,39(9):1213-1219
采用溶胶凝胶-燃烧法合成了系列不同掺杂浓度Y3+和Gd3+的LaBO3∶Eu3+发光粉,对其结构、形貌和发光性能进行了表征。XRD研究结果表明:发光粉的结构与基质掺杂离子的种类和掺杂浓度有关系。荧光光谱结果表明:适量比例Y3+和Gd3+离子掺杂将提高LaBO3∶Eu3+发光粉的发光强度。Y3+和Gd3+离子最佳掺杂摩尔分数分别为1.5%和12.5%。5D07F25D07F1跃迁发射的相对强度比值说明:掺杂改变LaBO3∶Eu3+中Eu3+局域环境的对称性。发光性能改变主要受晶体结构、掺杂离子电负性影响。Gd3+离子掺杂更有利于发光粉结构稳定性和发光性能的改善。  相似文献   

10.
利用水热法制备得到NaYbF4:0.01%Tm3+,20%Eu3+上转换材料,利用X射线衍射分析、扫描电子显微镜及光谱测试技术分别对其进行了结构、形貌以及光谱性质的表征。在980 nm近红外激光激发下,得到了Eu3+的可见到紫外范围的上转换荧光发射。分析表明:共掺杂NaYbF4纳米材料中Tm3+到Eu3+离子的能量传递对布居Eu3+离子的激发态能级,获得Eu3+的上转换发光起着至关重要的作用。另外,在实验中首次获得了Eu3+对应于3P07Fj (j=0,1,2)能级跃迁的上转换光发射。  相似文献   

11.
Optical properties of Eu3? ions in oxyfluoride glasses and glass ceramics doped with low concentration (0.1 mol%) have been analysed and compared with previous results for high concentrated samples (2.5 mol%). The Eu3? ions in the low dopant concentration glass ceramics are diluted into like crystalline environments with higher symmetry and lower coupled phonons energy than in the precursor glasses. Fluorescence line narrowing measurements indicate the presence of two main fluoride site distributions for the Eu3? ions in these low concentrated glass ceramics.  相似文献   

12.
Eu3+ ion doped chlorophosphate glass ceramics containing nanocrystals were successfully prepared, and their spectroscopic characterizations were done using absorption, excitation and emission spectra. For the crystallized samples, X-ray diffraction (XRD) and transmission electron microscopy (TEM) experiments evidenced the formation of CaCl2 nanocrystals. The absorption and emission spectra investigations indicate that a considerable amount of Eu3+ ions was trapped in CaCl2 nanocrystals, and therefore an efficient up- and down-frequency conversion was observed. The comparative spectroscopic studies of Eu3+ doped samples suggest that the investigated glass ceramics systems are potentially applicable as frequency-conversion photonics devices.  相似文献   

13.
应用激光光谱学技术,探讨了Tm3+离子掺杂透明氟氧化物玻璃陶瓷体系中声子调控对红色激光抽运荧光辐射性质的影响. 研究了基质结构和样品环境温度与电声子相互作用的联系以及声子变化对于荧光辐射产生的影响. 发现改变基质材料的SiO2含量能影响蓝色上转换荧光效率. 另外,依据温度与声子能量之间的联系,通过改变样品环境温度可明显调节低声子基质材料中掺杂离子激发态能级的布居速率,改变上转换效率. 关键词: 荧光辐射 声子 无辐射弛豫 荧光寿命  相似文献   

14.
二氧化锆纳米材料中Eu3+的发光特性   总被引:2,自引:0,他引:2       下载免费PDF全文
研究了掺1mol%Eu3+的二氧化锆纳米材料随退火温度变化的发光性质,得到退火温度为600和800℃的样品中Eu3+5D07F2发射在604nm处,这种现象不多见. 几种经不同退火温度处理的纳米材料样品在紫外光的照射下,稀土离子Eu3+5D07F2发射的发光逐 关键词: 二氧化锆 纳米材料 3+')" href="#">Eu3+ 发光  相似文献   

15.
Blue light-emitting glasses were successfully prepared by doping Eu2+ ions in the system Al2O3-SiO2. The Al2O3-SiO2 glasses doped with Eu3+ ions were synthesized using a sol-gel method, followed by heating in hydrogen gas atmosphere to reduce into the Eu2+ ions. The obtained glasses exhibited emission spectra with peak at ∼450 nm due to 4f65d→4f7 (8S7/2) transition, the intensities of which strongly changed depending on their glass composition and heating conditions. The emission quantum efficiency of 48% was achieved by heating the glass with the ratio of Al3+ to Eu3+ at about 6 at 1000 °C in hydrogen gas atmosphere. It was found that the Al2O3-SiO2 glasses were appropriate not only for homogeneously doping the Eu3+ ions in glass structure but also reducing to Eu2+ ions, resulting in enhanced blue light-emission properties.  相似文献   

16.
Rare-earth doped xerogels (Eu3+, Sm3+, Ho3+, Pr3+) were prepared by using the sol-gel method and their magneto-optical and optical properties have been studied. The Magnetic Circular Dichroism (MCD) spectra are quite similar to those recorded in the RE-doped fluorozirconate glasses; the fine structures shown by the MCD spectra are better resolved compared to the optical absorption spectra. The MCD technique has been correlated with optical measurements in order to investigate the site symmetry in the particular case of Eu3+-doped xerogel and oxyfluoride glasses. In the xerogel, coordination symmetry around the Eu3+ ions is close to D3h and is lower in the oxyfluoride glass.  相似文献   

17.
Zinc phosphate glasses doped with Gd2O3:Eu nanoparticles and Eu2O3 were prepared by conventional melt-quench method and characterized for their luminescence properties. Binary ZnO-P2O5 glass is characterized by an intrinsic defect centre emission around 324 nm. Strong energy transfer from these defect centres to Eu3+ ions has been observed when Eu2O3 is incorporated in ZnO-P2O5 glasses. Lack of energy transfer from these defect centres to Eu3+ in Gd2O3:Eu nanoparticles doped ZnO-P2O5 glass has been attributed to effective shielding of Eu3+ ions from the luminescence centre by Gd-O-P type of linkages, leading to an increased distance between the luminescent centre and Eu3+ ions. Both doped and undoped glasses have the same glass transition temperature, suggesting that the phosphate network is not significantly affected by the Gd2O3:Eu nanoparticles or Eu2O3 incorporation.  相似文献   

18.
研究了退火温度对ZrO2纳米材料中Eu3+离子发光性质的影响. 材料的结构、晶粒尺寸和形状以及晶格的排列分别由XRD,TEM表征. 结果表明:用共沉淀法制备的ZrO2纳米材料具有不随退火温度变化、稳定的四方结构;材料的晶粒尺寸随退火温度的提高而增大;晶格的排列由无序逐渐变为有序;发射光谱表明其主要发射在595 nm和604 nm处;在394 nm的紫外光辐照下得到了不同样品的604 nm荧光发射强度的变化不同. 这种现象与样品中O2-离子含量和样品表面的表面缺陷有关;另外,电荷迁移带随退火温度的变化而变化.  相似文献   

19.
采用高温熔融法和热处理工艺制作了含有GdF3纳米晶的氧氟微晶玻璃。在386 nm激发下,Dy3+掺杂氧氟微晶玻璃的发光强度明显增强,且蓝光对黄光的发光强度比逐渐增大,表明Dy3+已进入到GdF3纳米晶中。在980 nm激光器泵浦下,Er3+,Yb3+共掺氧氟微晶玻璃的上转换发光随着热处理温度的升高明显增强,Er3+的上转换发光出现明显的Stark分裂现象,这亦说明Er3+已进入到GdF3纳米晶相中。通过研究上转换发光强度与泵浦功率的关系,确定绿光上转换发光为双光子过程。  相似文献   

20.
Europium doped glass-ceramics containing BaF2 nano-crystals have been prepared by using the controlled crystallization of melt-quenched glasses. X-ray diffraction and transmission electron microscopy have confirmed the presence of cubic BaF2 nano-crystalline phase in glass matrix in the ceramized samples. Incorporation of rare earth ions into the formed crystalline phase having low phonon energy of 346 cm−1 has been demonstrated from the emission spectra of Eu3+ ions showing the transitions from upper excitation states 5DJ (J = 1, 2, and 3) to ground states for the glass-ceramics samples. The presence of divalent europium ions in glass and glass-ceramics samples is confirmed from the dominant blue emission corresponding to its 5d-4f transition under an excitation of 300 nm. Increase in the reduction of trivalent europium (Eu3+) ions to divalent (Eu2+) with the extent of ceramization is explained by charge compensation model based on substitution defect mechanisms. Further, the phenomenon of energy transfer from Eu2+ to Eu3+ ion by radiative trapping or re-absorption is evidenced which increases with the degree of ceramization. For the first time, the reduction of Eu3+ to Eu2+ under normal air atmospheric condition has been observed in a BaF2 containing oxyfluoride glass-ceramics system.  相似文献   

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