Eu^(2+)在磷酸镧中的发光及Ce^(3+)→Eu^(2+)的能量传递  

Luminescence of Eu^(2+) and Energy Transfer from Ce^(3+)to Eu^(2+) in Lanthanum Phosphate

作　　者：朱汇[1] 熊光楠[1] 

机构地区：[1]天津理工学院材料物理研究所,天津300191

出　　处：《发光学报》2003年第3期234-238,共5页Chinese Journal of Luminescence

基　　金：天津市自然科学基金资助项目(01360191);天津市"材料物理与化学"重点学科资助项目

摘　　要：采用高温固相反应合成了LaPO4∶Eu2+和LaPO4∶Ce3+,Eu2+样品,报道了Eu2+在LaPO4中的发光性质和Ce3+→Eu2+的能量传递现象。文中探讨了Ce3+→Eu2+的能量传递机理,根据Dexter电多极相互作用的理论证明其为偶极子 偶极子相互作用的共振能量传递。A new luminescence material——LaPO4 doped with Eu2+ and Ce3+ was prepared by high temperature solid state reaction. And the optical properties of Eu2+activated and Ce3+,Eu2+ coactivated lanthanum phosphates were investigated by using photoluminescence(PL) measurements.Emission spectrum of LaPO4∶Eu2+ recorded at room temperature with 324nm excitation shows a broad emission band centered at 423nm. And it is possible to determine the distribution of this broad emission band in the spectrum associated with transition from the 4f5d level of Eu2+ ion.The excitation spectrum of Eu2+activated lanthanum phosphate recorded at room temperature monitoring 423nm emission exhibits absorption in UV region (220～400nm) assigned to the 4f→5d transition of Eu2+ ion.Lanthanum phosphate doped with Ce3+ was also prepared by high temperature solid state reaction. The room temperature photoluminescence spectra of LaPO4∶Ce3+ show the broad emission and excitation band of Ce3+ ion ,around 342nm and 284nm,respectively.From these spectra above, it's possible to deduce that energy transfer between the Eu2+ and Ce3+ ion will probably happen because of the well overlapping between Ce3+ emission and Eu2+ excitation. And it's well proved in the excitation spectrum of LaPO4 coactivated by Eu2+ and Ce3+ at room temperature, monitoring Eu2+ emission. This spectrum shows a strong absorption band of Ce3+, ranging over 220～340nm, in addition to original f→d transition of Eu2+(220～400nm). That is to say there happens a sensitization of Eu2+ by the presence of Ce3+ ion. The Eu2+ emission intensity of LaPO4∶Ce3+001, Eu2+001 is 56 times higher than that of the corresponding phosphor activated by Eu2+ only.A series of LaPO�

关 键 词：EU^2+ 铕离子 磷酸镧 发光 CE^3+ 能量传递 铈离子 偶极子-偶极子相互作用 

分 类 号：O614.331[理学—无机化学] O482.31[理学—化学]