Ce3+,Mn2+激活氟磷酸钙的发光中心及其相互作用

研究了Ce3+,Mn2+激活的氟磷酸钙(FAP:Ce3+,Mn2+)的发光光谱、激发光谱、漫反射光谱、发光衰减以及顺磁共振谱,首次发现了FAP:Ce3+,Mn2+中Ce3+可以形成两种发光中心;同时也发现在该材料中Mn3+的发光中心与普通卤粉相似,即存在MnⅠ和MnⅡ两种中心;研究表明,由Ce3+中心向Mn2+中心的能量传递具有相当高的效率,传递机制属偶极子-偶极子相互作用;在Ce3+→Mn2+能量传递过程中,MnⅠ中心优先被Ce3+中心敏化。

LUMINESCENCE CENTER IN Ce-Mn ACTIVATED CALCIUM FLUOROPHOSPHATE AND THE INTERACTION BETWEEN THE CENTERS

In this paper, the selective excitation emission spectra, excitation spectra,luminescence decay,diffuse reflection spectra and EPR spectra of Ce-Mn activated calcium fluorophosphate are measured and analysed,two sort of Ce luminescence centers are first discovered and their situation are suggested, the energy transfer from Ce centers to Mn centers is studied.Two series of Ce3+ emission spectra have been observed by means of selective excitation. One is double peak structure with the main emission peak at 332nm when the sample is excited at 254nm, the other is also double peaks structure with the main peak at 332nm when the sample is excited at 337nm. It is affirmed by analysing these spectra that the double peaks structure originate from the 5d-2F7/2 and 5d-2F5/2 transitions of Ce respectively. And the two series structure come from two kinds of luminescence centers(labslled Ce Ⅰ and Ce Ⅱ). Comparing the excitation spectra of Ce Ⅰ and Ce Ⅱ with the absorption spectra of FAP:Ce, it can be found that of Ce formed Ce Ⅰ centers.