Eu^(3+)激活的Li_2Gd_4(MoO_4)_7钼酸盐红色荧光体及其发光性质  

Red Li_2Gd_4(MoO_4)_7:Eu^(3+) Molybdate Phosphors and Their Luminescent Properties

作　　者：韩建伟[1] 林林[2] 童玉清[1] 羊富强 曹林[4] 刘行仁[5] 

机构地区：[1]深圳职业技术学院工业中心,广东深圳518055 [2]福建师范大学物理与光电信息科技学院,福建福州350007 [3]中国检验检疫科学院检测技术与装备所,北京100123 [4]北京科技大学电镜实验室,北京100088 [5]中国科学院长春光机与物理所,吉林长春130033

出　　处：《稀土》2012年第3期50-54,共5页Chinese Rare Earths

基　　金：深圳职业技术学院自然科学研究项目(2209K3170038)

摘　　要：由高温固相反应首次合成Li2(Gd1-xEux)4(MoO4)7(0<x≤1.0)红色荧光体并研究其晶体结构及发光性质。经检测,发现材料结构属于四方晶系白钨矿。Eu3+的激发光谱主要是由Eu3+的较高4f能级跃迁激发谱及次要的Mo6+和Eu3+的电荷转移带CTB组成。其中最强的激发(吸收)谱线分别为465nm(7F0→5D2)及395nm(7F0→5L6)。其发射色纯度很高的红光,发射峰为614nm和611nm。讨论在许多Eu3+激活的钼/钨酸盐荧光体中产生高浓度猝灭的原因。碱金属离子(如Li+,Na+等)和位于阳离子格位上的空位Φ在Eu3+浓度猝灭过程中扮演重要角色。对Eu3+-Eu3+之间的无辐射能量传递过程起阻塞作用,而且使Eu3+-Eu3+离子间的距离增加。在Li2(Gd1-xEux)4(MoO4)7(0<x≤1.0)中,Eu3+激活剂浓度x可高达0.5mol以上,Li2(Gd1-xEux)4(MoO4)7(0<x≤1.0)也是一种高效的红色荧光体。这类Eu3+激活的钼酸盐可望用作白光LED的红色荧光体。Eu3＋-activated Li2（Gd1-xEux）4（MoO4）7（LGMEu,0〈x≤1.0） red phosphors were synthesized by solid-state reaction.The crystal structure and photoluminescent properties of the phosphors were investigated for the first time.The XRD data of LGM host and LGMEu phosphors confirmed that the samples are of single phase with the tetragonal scheelite structure.The excitation and emission spectra of LGMEu samples indicate that the red phosphors can be effectively excited by near ultraviolet（395nm,7F0→5L6） and blue（465nm,7F0→5D2） lights and emitted red light with the peaks of 614nm and 611nm with high color purity.A weaker signal of the charge transfer band（CTB） in UV region of 270~350nm was observed.The importance of Eu3＋ concentration quenching in LGM：Eu phosphors was discussed.The alkali metal ions and vacancies Φ located at the sites of cation have played an important role in the process of Eu3＋ concentrature quenching.It can be explained by the blocking effects in the process of nonradiative energy transfer between Eu3＋-Eu3＋ and to increase the distance between Eu3＋-Eu3＋ ions.The optimum Eu3＋ concentration for Li2Gd4（MoO4）7 system is 50mol%,and Li2Eu4（MoO4）7 is an efficient red phosphor.These results suggest that Li2Gd4（MoO4）7：Eu could be a potential red phosphor for light-emitting diode.

关 键 词：钼酸盐 Eu3+ 发光 红色荧光体 浓度猝灭 

分 类 号：O482.31[理学—固体物理]