摘要
采用高温固相法制备了两种新型的红色荧光粉KMGd1-x(MoO4)3∶xEu^3+(M=Ca、Sr),并研究了它们的结构、形貌、浓度与温度猝灭效应及封装后LED灯珠的发光特性.结果表明,KCaGd1-x(MoO4)3∶xEu^3+始终保持四方白钨矿结构,而KSrGd1-x(MoO4)3∶x Eu^3+的晶体结构则随会着Eu^3+离子掺杂浓度的增大而发生变化.两种荧光粉在394与465nm处均具有较强的吸收,刚好与商用InGaN半导体芯片发射波长相匹配.在394nm激发下,两种荧光粉的主发射峰均位于616nm处,Eu^3+离子的最佳掺杂浓度分别为80%(M=Ca)和90%(M=Sr).基于横向穿越机制分析了荧光粉的热猝灭效应,热激活能分别为0.246eV(M=Ca)和0.250eV(M=Sr).两种荧光粉的荧光衰减曲线均呈单指数变化,且荧光寿命受Eu^3+浓度影响很小.
Two kinds of new red phosphors KMGd(MoO4) 3∶Eu^3+(M=Ca,Sr) were synthesized by high-temperature solid reaction method and their structure,morphology,concentration and thermal quenching effects,as well as the photoluminescent performance of LED fabricated with them were investigated.The results showed that the KCaGd1-x (MoO4) 3∶x Eu^3+ with all Eu^3+ concentrations belonged to tetragonal symmetry with scheelite structure,while the structure of KSrGd 1-x (MoO4) 3∶x Eu^3+ changed with the increment of Eu^3+ concentration.Both of the phosphors exhibited two intensive absorption bands at 394 and 465 nm,which were consistent with the emission wavelength of commercial InGaN chip.Under the excitation of 394 nm,both of the phosphors showed a dominant emission peak at 616 nm,and the optimum concentrations of Eu^3+ ions were 80mol%(M=Ca) and 90mol%(M=Sr) respectively.On the basis of crossover mechanism,the concentration quenching effect was analyzed and the activation energies were 0.246 eV (M=Ca) and 0.250 eV (M=Sr) respectively.The luminescent decay curves of both phosphors exhibited a single exponential behavior and the lifetime was hardly effected by the Eu^3+ concentrations.
作者
宋明君
台夕市
张娜娜
王林同
SONG Mingjun;TAI Xishi;ZHANG Nana;WANG Lintong(School of Chemistry & Chemical Engineering,Weifang University,Weifang 261061,China)
出处
《功能材料》
EI
CAS
CSCD
北大核心
2019年第6期6109-6115,共7页
Journal of Functional Materials
基金
山东省自然科学基金资助项目(ZR2016BQ40,ZR2018QEM003,ZR2017BEE038)
关键词
钼酸盐
红色荧光粉
浓度猝灭
激活能
molybdate
red phosphors
concentration quenching
activation energy
