980nm激发下Er^(3+)/Yb^(3+)共掺杂ZrO_2-Al_2O_3粉末的上转换发光特性

The upconversion luminescent of Er^(3+)/Yb^(3+) co-doped ZrO_2-Al_2O_3 powders

通过固相反应法制备了Er3+/Yb3+共掺杂ZrO2-Al2O3粉末的样品,并对样品在980nm激光激发下的上转换发光特性进行了研究.从发射光谱可以发现,在可见光范围内有3个强的发光带,一个位于654nm附近的红光带和两个分别位于545nm、525nm附近的绿光带,分别对应于Er3+离子的以下辐射跃迁:4F9/2→4I15/2、4S3/2→4I15/2、2H11/2→4I15/2.其中又以Er3+离子的4F9/2→4I15/2跃迁产生的红色荧光辐射最强.对其上转换发光机制进行了分析,发现这三个发光过程都是双光子过程.对样品粉末进行了XRD检测,发现ZrO2主要以立方相为主,并且计算得到了这种立方结构的晶格常数.Al2O3固溶于ZrO2中,Al3+嵌入ZrO2后产生氧空位,导致ZrO2晶体的对称性降低,这种结构变化更有利于提高上转换效率,即上转换发光强度增强.

Samples of Er^3＋/Yb^3＋ co-doped ZrO2-A1203 powders were prepared by solid-state reaction. The upconversion luminescence spectrum excited by 980 nm laser light suggests that there exit three main emission bands： one red emission band centered at 654 nm and two green emission bands centered at 545 and 525nm, corresponding to Er^3＋ ions transitions of ^4F9/2→^4I15/2、^4S3/2→^4I15/2 and ^2H11/2→^4I15/2, respectively. The emission band centered at 654 nm is much stronger than the other two. The upconversion mechanisms are discussed and it is found that both red emission and green emissions are two-photon processes. It can be seen from the XRD spectra that zirconia （ZrO2 ） mainly exists as a cubic phase, while Al^3＋ is implanted into the ZrO2 lattice, producing the ZrO1.87. The solid solution towers the site symmetry of the lattices in ZrO2 crystals, which promotes the upconversion efficiency.