摘要
采用溶液燃烧法在600℃成功合成了(BaxMg)2/(x+1)Al10O17∶Eu2+(0.6≤x≤1.2)蓝色荧光粉,着重研究了基质阳离子Ba/Mg比值的变化对其晶体结构及发光特性的影响。结果表明,合成的产物为纯相,且随Ba/Mg比值的增加,样品的晶格参量逐渐增加;当Ba/Mg比增加时,发射光谱的强度明显增强,至Ba/Mg为0.9时达到最大值,然后随Ba/Mg比继续增大,发射光谱的强度反而下降;Ba/Mg比值减少,导致基质的晶场增强和电子云膨胀效应的发生,致使Eu2+发射主峰向长波方向移动。Eu2+的掺杂浓度对样品的发光性能有显著的影响,随Eu2+浓度增大,发光中心增多,Eu2+离子间相互作用增强,能量传递加快,发光强度逐渐增大,并达到一个最大值。此后,随Eu2+的浓度进一步增加,Eu2+之间的能量传递速率将超过发射速率,呈现浓度猝灭特性。
Abstract： The （BaxMg）2/（x＋1）Al10O17∶Eu^2＋（0.6≤x≤1.2） （BAM） phosphors with different Ba/Mg ratio were successfully prepared by solution combustion method at 600℃. The influence of Ba/Mg ratio on the crystal structure and luminescent properties of the obtained samples were mainly investigated. The results show that the samples are of single phase, and the lattice parameters increase with the Ba/Mg ratio. Moreover, the intensity of the fluorescence of the resulting phosphors increases obviously with the Ba/Mg ratio, and the maximum emission intensity is reached at Ba/Mg ： 0. 9 . However , as Ba/Mg ratio was higher than 0. 9, the intensity of the fluorescence is reduced reversely. Furthermore, with the decrease of the Ba/Mg ratio, the emission peak of the phosphors shifts to the longer wavelength due to the crystal field enhancement and electron cloud expansion. Moreover, the luminescent property of BAM phosphor is considerably influenced by Eu^2＋ concentration. In an appropriate Eu^2＋ doping concentration range, the intensity of the fluorescence of BAM increase obviously with Eu^2＋ doping concentration and reaches a maximum, owing to more luminescent centers and faster energy transfer between Eu^2＋ ions. However, as the Eu^2＋ doping concentration is higher than a critical value, the intensity of the fluorescence is reduced reversely, due to the concentration quenching as the energy transfer rate between Eu^2＋ ions exceeds the emission rate.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2007年第1期111-115,共5页
Acta Optica Sinica
基金
国家自然科学基金(50276023
50574042)资助课题
