摘要
高温固相法合成了Ce3+掺杂的Y3Al5O12(YAG)样品,研究了样品的结构、光致发光和热释发光性质.X射线衍射分析结果表明合成样品为YAG纯相,稀土离子的少量掺杂不改变基质YAG的结构.荧光光谱测试表明在高温空气气氛下Y2.95Al5O12∶Ce40.+05制备过程中存在Ce4+的自还原现象,一部分Ce4+被自还原为Ce3+,导致531nm黄光宽带发射.弱还原气氛下制备的Y2.95Al5O12∶Ce30.+05在紫外光照射后具有黄色长余辉,余辉时间长达35min.热释光测试表明在Ce3+掺杂的YAG样品中存在热释发光,在弱还原气氛下制备的样品Y2.95Al5O12∶Ce30.+05的热释光随温度变化曲线上有112℃和256℃两个明显的热释光峰;而在空气气氛下制备的样品Y2.95Al5O12∶Ce40.+05的热释光随温度变化曲线上只有128℃一个明显的热释光峰.通过对比研究,热释发光主要来源于YAG基质中缺陷能级所陷俘的Ce3+.
Cerium-doped yttrium aluminium garnet （Y3Al5O12,YAG） samples were synthesized by the conventional solid state reaction method. The structure,photoluminescence and thermoluminescence properties were studied. The prepared samples are identified as pure garnet structure by the XRD results. The doping of a small amount of cerium ions has no influence on the structure of the host. Fluorescence spectra show that in the process of the preparation of Y2.95 Al5O12∶Ce04 .＋05 there is self reduction of Ce4 ＋ when calcined in air,Which makes Y2.95 Al5O12∶Ce04 .＋05 emit yellow light peaking at 531 nm when excited by blue light,because a part of Ce4 ＋ have been reduced into Ce3 ＋ . Y2.95Al5O12∶ Ce03 .＋05 prepared in weak reducing atmosphere has long yellow afterglow lasting for 35 minutes after it is excited by ultraviolet light. Thermoluminescence measurements show that YAG samples doped with Ce3 ＋ can emit light at higher temperature. There are two obvious thermoluminescence peaks located at 112 ℃ and 256 ℃ in the thermoluminescence curve of Y2.95Al5O12∶ Ce03 .＋05 prepared in weak reducing atmosphore while there is only one located at 128 ℃ in the thermoluminescence curve of Y2.95Al5O12∶ Ce40 .＋05 prepared in air. A conclusion that the thermoluminescence of YAG∶ Ce3 ＋ originates mainly from the Ce3 ＋ trapped by defect energy level can be made out by comparing the cases of doped samples and the un-doped ones.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2011年第1期182-187,共6页
Acta Physica Sinica
基金
国家自然科学基金(批准号:20871033,21071034)资助的课题~~
关键词
长余辉
高温热释光
缺陷
long afterglow
thermoluminescence at higher temperature
defect
