Sr_2MgSi_2O_7∶Eu,Nd体系中Eu~(2+)向Nd~(3+)的能量传递

通过高温固相法合成了Sr2MgSi2O7∶Eu2+,Nd3+发光材料,测试了样品的物相结构、可见和近红外激发和发射光谱、荧光寿命等,研究了Eu2+对Nd3+的近红外发光性能的影响及近红外发光相对强度变化的规律,考察了煅烧温度、煅烧时间对近红外发光性能的影响。结果表明,1200℃下煅烧的Sr2MgSi2O7∶0.02Eu2+,0.01Nd3+样品近红外发光强度最强,Eu2+对Nd3+的近红外发光敏化效果最好。证实了在Sr2MgSi2O7∶Nd3+,Eu2+体系中Eu2+通过无辐射传递的模式向Nd3+有效传递了能量。     

用于白光LED的荧光粉Sr3MgSi2O8:Eu2+的发光特性

使用高温固相法制备不同NH4Cl(作为助熔剂)加入量和不同Eu2+浓度的Sr3MgSi2O8:Eu2+,并研究其成相和发光性质.研究结果表明:NH4Cl加入量为24%时,样品为纯相,发光最强.Sr3MgSi2O8:Eu2+样品在近紫外区存在强激发带(250～400 nm),谱峰位于366 nm相应的发射谱带位于蓝光区(420～500nm),为一个不对称宽带,谱峰位于457 nm,该发射带由两个发射峰组成,其位置较接近,因此不能复合出白光,Sr3MgSi2O8:Eu2+仅适合作为紫外LED芯片激发的蓝光荧光粉.     

Eu2+、Er3+共掺杂Sr3MgSi3O10高亮度蓝色荧光粉的制备及性质研究

采用凝胶-燃烧法在活性炭弱还原气氛下成功合成了高亮度蓝色发光材料Sr3 MgSi3 O10:Eu2+,Er3+.用X射线粉末衍射仪、荧光分光光度计对样品的物相结构和发光性质进行了分析和表征.结果表明,所合成的Sr3 MgSi3O10:Eu2+,Er3+的晶体结构与Sr2 MgSi2 O7的相似,属四方晶系.样品激发光谱是位于250 nm～450 nm的宽带,最大激发峰位于357 nm处;发射光谱也是一宽带,最强的发射峰位于466 nm处,属于Eu2+典型的4f65d1→4f7跃迁,呈蓝光发射.根据光谱测定结果和Van Uitert经验公式,推断Eu2+进入Sr3 MgSi3 O10基质后占据八配位Sr的格位.研究发现,共掺杂Er3+能有效敏化Sr3 MgSi3 O10基质中Eu2+的发光,当Er3+的掺杂摩尔分数为0.04时,样品发光强度最大,约为单掺Eu2+样品发光强度的3.3倍.     

红色Sr1-2xNaXWO4:Eu3+x荧光体的制备与发光性能

采用传统高温固相法,以钨酸锶为基质材料,掺杂稀土Eu3+制备了可被紫色光有效激发的红色荧光粉Sr1-2xNaxWO4:Eu3+x.通过测定与分析样品Sr1-2xNaxWO4:Eu3+x的激发和发射光谱,发现激发光谱在395nm处吸收值最大,发射光谱的发射主峰位于613nm处,属于Eu3+的5 D0→7F2特征跃迁.不同的Eu3+掺杂浓度下样品发光强度不同,当x =0.07时发光强度最佳.电荷补偿剂Na+对样品发光强度的影响很大,主要原因是Na+的加入会影响基质的晶体结构,当Na+的含量与Eu3+含量相同时样品发光强度最好,Na+含量增加到一定程度后基质结晶不完善,荧光体的发光强度急剧下降.     

Investigation on luminescence properties of Ln^3＋ doped Sr3EuMgSi2O8 （Ln=Dy, Er, Ho）

The luminescent properties of Sr2.97MgSi2O8:Eu2+0.01 phosphors were investigated with different Ln3+0.02(Ln3+:Dy3+,Er3+,Ho3+) co-dopants. The co-dopants had no influence on both the structure of the lattice and the position of the emission peak. However, the afterglow properties of samples were enhanced with different co-dopants. The afterglow duration of the Dy3+ co-doped sample was longer than that of the others. Furthermore, the co-doping samples had stronger thermoluminescence (TL) intensity and therefore longer afterglow duration. At last, the self-reduction of Eu3+→Eu2+ was observed in an silicate compound of Sr3-xMgSi2O8:xEu phosphor in air condition. This is the first time to show a blue long afterglow phosphor synthesized avoiding reducing atmosphere.     

溶胶-凝胶法制备La2Ce2O7:Eu3+及其发光性能

采用溶胶-凝胶法（Sol-gel）合成La₂Ce₂O₇:Eu3+系列红色荧光粉,并研究煅烧温度、Eu3+掺杂浓度以及不同种类电荷补偿剂对样品发光性能的影响.通过XRD、SEM、荧光光谱对样品的晶体结构、形貌以及发光性能进行测量和表征.结果表明:实验所得样品主晶相为La₂Ce₂O₇,属于萤石结构. Eu3+及电荷补偿剂的掺杂没有改变其晶体结构.合成的样品在467 nm蓝光激发下发出612 nm的红光.样品的发光强度随煅烧温度以及Eu3+掺杂浓度的提高先增强后减弱,样品的较优的煅烧温度为1 100 ℃,Eu3+较优的掺杂浓度为10 %（摩尔百分比）.掺入电荷补偿剂可以有效增强样品的发光强度,其中掺入Li+后发光增强的效果最显著.      

复合熔盐法合成Y2O3.Eu3+红色荧光粉

以草酸钇铕(Y2(C2O4)3:Eu3+)为前驱体,采用复合熔盐(NaCl+S+Na2CO3)协助焙烧法合成Y2O3:E.u3+红色荧光粉.利用XRD、SEM、光谱分析等测试和分析荧光粉粒径、颗粒形貌以及发光性能.主要考察复合熔盐配比、用量以及焙烧温度和时间对Y2O3:Eu3+荧光粉发光性能的影响.结果表明,NaCl在...     

Eu3+掺杂Sr2CeO4荧光体的制备、发光性能及能量传递

采用柠檬酸-凝胶法成功地制备了Eu3+掺杂的Sr2CeO4荧光体.用X射线粉末衍射、拉曼光谱、紫外可见吸收光谱和荧光光谱等分析手段研究了荧光体的结构、光致发光性能及能量传递.结果表明,Sr2CeO4∶ Eu荧光体的激发光谱由两部分组成一个宽的激发带和属于Eu3+的f - f跃迁的锐线谱(峰位是395nm、466nm、532nm),它的发射光谱中除了出现常见的发射峰如585nm(5D0→7F1) 、616nm(5D0→7F2)、655nm(5D0→7F3)和704nm(5D0→7F4)外,还包含有来自较高能级激发态5D1的跃迁的发射,即509nm(5D1→7F0)、534nm(5D1→7F1)、554nm(5D1→7F2).这些发射峰在其它基质材料中难以观察到.发射主峰位于616nm附近,没有出现5D0→7F0的跃迁发射,这表明Eu3+在Sr2CeO4基质中处于无反演中心或偏离反演中心的格位上.Sr2CeO4∶Eu荧光体中存在着从基质Sr2CeO4到Eu3+的能量传递.     

SrAl2O4∶Eu2+,Dy3+磷光粉低成本制备工艺及发光性能研究

以工业铝酸钠溶液制备的氢氧化铝为铝基原料,采用高温固相反应法合成了SrAl2O4∶Eu2+,Dy3+磷光粉,考察了稀土掺杂量、烧结温度及硼酸加入量对其发光性能、激发光谱及发射光谱的影响,并通过XRD谱及余辉衰减曲线对最佳工艺条件下制备的样品进行表征。结果表明,当稀土掺杂量x(Eu)=3%、x(Dy)=3%,烧结温度为1 300℃,烧结时间为4h,硼酸加入量w(H3BO3)=9%时,所制备磷光粉样品仍保持SrAl2O4的晶体结构,其发光性能最好,发光强度最大,主激发波长在360nm左右,主发射波长在510nm左右;余辉为黄绿色,衰减时间长。     

掺杂 Eu3+ 的 Na24P2Mo22O83 的合成及其发光特性

采用固相反应法合成了掺杂Eu3 的新型杂多酸盐Na2 4 P2 Mo2 2 O83 荧光体 ,并通过元素分析、红外光谱、X射线粉末衍射对其组成及结构进行了表征 ,新型杂多酸盐Na2 4 P2 Mo2 2 O83 属正交晶系 ,晶胞参数a =1 4774nm ,b =1 1896nm ,c=1 10 42nm ,属D2 4 -P2 12 12 1(No.19)空间群。测定了其激发光谱和发射光谱 ,探讨了掺杂Eu3 离子的Na2 4 P2 Mo2 2 O83 的发光特性。     

Phase structure and temperature dependent luminescence properties of Sr2LiSiO4F: Eu2+ and Sr2MgSi2O7: Eu2+ phosphors

Green-emitting Sr2LiSiO4F:Eu2+ and blue-emitting Sr2MgSi2O7:Eu2+ phosphors were synthesized by the conventional high temperature solid-state route,respectively.Their structures and photoluminescenee properties were comparatively investigated.It was found that the mixture phases of Sr2MgSi2O7 and SrF2 were obtained when a part of Sr2+ in Sr2LiSiO4F was replaced by some amount of Mg2+ in order to design the possible SrMgLiSiO4F:Eu2+ phosphor.Based on the photoluminescence analysis,Sr2LiSiO4F:Eu2+ phosphor exhibited a green broad emission band of main peak at 513 nm under the excitation of 365 nm,while the Sr2MgSi2O7:Eu2+ and SrMgLiSiO4F:Eu2+ phosphor showed blue emission centered at 467 nm.The temperature dependent photoluminescence properties and room temperature decay time for the three kinds of phosphors were also discussed in this paper.     

蓝色发光材料Sr_2MgSi_2O_7∶Eu~(2+),Dy~(3+)的微波合成及性能

采用微波辐射法合成了Sr2MgSi2O7∶Eu2+,Dy3+粉末,研究了微波辐射功率和加热时间对制备Sr2Mg-Si2O7∶Eu2+,Dy3+的影响,确定了微波法合成Sr2MgSi2O7∶Eu2+,Dy3+的最佳条件,并用x射线衍射(XRD)、荧光光谱等测试手段对其进行了表征。XRD结果表明,合成的Sr2MgSi2O7∶Eu2+,Dy3+属于四方晶系。荧光光谱测试表明,用lem=467nm作为监控波长,在200nm~450nm之间有宽的激发光谱,峰值位于398nm。用lex=398nm激发样品,其发射光谱为一宽带,峰值位于467nm。Sr2MgSi2O7∶Eu2+,Dy3+的荧光强度和余辉性能随辐射功率和时间的不同而发生变化,其中以辐射功率720W,反应时间25min时荧光强度最强,余辉时间可达8h。     

Synthesis of Long Afterglow Photoluminescent Materials Sr_2MgSi_2O_7∶Eu~(2 ), Dy~(3 ) by Sol-Gel Method

Withtheprogressofsocialcivilizationanddevel opmentofmodernscienceandtechnology ,thedemandforluminescentmaterialskeepsincreasingduetoitsgreatsocialandeconomicbenefits .Therefore ,prepa rationofluminescentmaterialswasregardedbypeopleveryearly .Asanembellish…     

溶胶-凝胶法制备Sr2MgSi2O7:Eu发光材料及其性能研究

采用凝胶-凝胶法制备了Sr1.98Eu0.02MgSi2O7发光材料.XRD的结果表明,所制备得到的发光材料主要由镁黄长石型结构的Sr2MgSi2O7组成;扫描电镜的结果表明,在实验的烧成温度下,在烧结过程中出现了明显的液相.荧光分析结果表明,该材料的主要激发峰位于353nm处,而主要的发射峰则位于468nm处,是典型的Eu2+的4f65d1→4f7的跃迁引起的.     

Synthesis and Luminescence Properties of Ba2 MgSi2 O7 :Eu2+ under UV Excitation

Eu2 activated pyrosilicate phosphor were prepared under a reducing atmosphere by solid-state reaction.The crystal structure of Ba2 MgSi2 O7: Eu2 was analyzed by XRD method.The excitation spectrum of Ba2MgSi2 O7; Eu2 is composed of two broad bands centered at about 310 nm and 395 nm respectively.In the emission spectra, the peak wavelength is at about 507 nm under 380 nm UV excitation.It was found that the introduction of Zn2 into Ba2MgSi2O7: Eu2 Can effectively increase its emission intensity without changing the position of emission peak.And the Eu2 and Ce3 codoped pyrosilicate phosphor is the efficient bluish green phosphor under the excitation of long UV light and its emission intensity is stronger than Eu2 doped pyrosilicate phosphor.     

Luminescence properties of composite material Sr2MgSi2O7:Eu2+,Dy3+/light conversion agent with multilayer structure

In order to improve the red luminescent properties,Sr₂ MgSi₂ O₇:Eu²⁺,Dy³⁺was selected as a blue persistent luminescent donor phosphor,while light conversion agent was utilized to tune the persistent luminescent spectra from blue to red.Composite red luminescent material Sr₂ MgSi₂ O₇:Eu²⁺,Dy³⁺/light conversion agent(SMED/LCA) was fabricated with light conversion agent and Sr₂ M...