Ca_4Y_6Si_6O_(25)∶Eu^(2+)绿色荧光粉的发光特性  

Luminescence Property of Ca_4Y_6Si_6O_(25)∶Eu^(2+) Green Phosphor

作　　者：杨志平[1] 闻建伟[2] 刘玉峰[1] 李立虎[1] 杨艳民[1] 周东站[1] 马淑媛[1] 于红伟[2] 

机构地区：[1]河北大学物理科学与技术学院,河北保定071002 [2]河北大学电子信息工程学院,河北保定071002

出　　处：《发光学报》2011年第1期7-11,共5页Chinese Journal of Luminescence

基　　金：国家自然科学基金(50902042);河北省自然科学基金(F2009000217)资助项目

摘　　要：采用高温固相法合成了Ca4Y6Si6O25:Eu2+绿色荧光材料。通过X射线衍射分析得知,Ca4Y6Si6O25属于六方晶系,具有P63/m(176)空间点群结构。测定了Eu2+的激发光谱和发射光谱。Ca4Y6Si6O25:Eu2+的激发光谱为350～450nm的宽带谱,这与近紫外光LED芯片相匹配。发射光谱是峰值为527nm的不对称宽带发射,这是因为Eu2+占据了晶格中Ca2+的位置,并产生了两种不同的发光中心。研究了Eu2+的含量对Ca4(1-x)Y6Si6O25:4xEu2+发光性能的影响,随着Eu2+浓度的增大,材料的发光强度先增强后减弱,Eu2+的最佳掺杂摩尔分数为20%(x=0.05)。根据Dexter理论得出,浓度猝灭机理为电四极-电四极相互作用。Ca4Y6Si6O25∶Eu2＋ green phosphor was prepared by high temperature solid-state reaction.The XRD speetrum indicates that Ca4Y6Si6O25 has a hexagonal crystal structure with a space group of P63/m（176）.The excitation and emission spectra of Ca4Y6Si6O25∶Eu2＋ were measured when the mole fraction of Eu2＋ was 20%.Its excitation spectrum is a broad band,from 350 nm to 450 nm,which matches with near ultraviolet LED chip.The emission spectrum of Ca4Y6Si6O25∶Eu2＋ exhibits an asymmetry broad band with the peak center at 527 nm,and it is because that Eu2＋ takes the place of Ca2＋ and forms two different luminescence centers.The effect of Eu2＋ concentration on Ca4（1-x）Y6Si6O25∶4xEu2＋ intensity was also investigated.With the increase of Eu2＋ concentration,the luminescence intensity of the green phosphor get to maximum and then decrease.The optimal mole fraction of Eu2＋ is 20%（x=0.05）.According to Dexter theory,concentration quenching can be attributed to quadrupole-quadrupole interaction

关 键 词：发光 荧光粉 Ca4Y6Si6O25∶Eu2+ 白光LED 

分 类 号：O482.31[理学—固体物理]