980 nm激发下Er3+/Yb3+共掺杂ZrO2-Al2O3粉末的上转换发光特性

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：⁴F_9/2→⁴I_15/2、⁴S_3/2→⁴I_15/2、 ²H_11/2→⁴I_15/2.其中又以Er³⁺离子的⁴F_9/2→⁴I_15/2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. 关键词： 3+/Yb³⁺')" href="#">Er³⁺/Yb³⁺ 上转换 2-Al₂O₃')" href="#">ZrO₂-Al₂O₃ 荧光 稀土

The upconversion luminescent of Er3+/Yb3+ co-doped ZrO2-Al2O3 powders

Samples of Er³⁺/Yb³⁺ co-doped ZrO₂-Al₂O₃ 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 Er³⁺ ions transitions of ⁴F_9/2→⁴I_15/2, ⁴S_3/2→⁴I_15/2 and ²H_11/2→⁴I_15/2, 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 Al³⁺ is implanted into the ZrO₂ lattice, producing the ZrO_1.87. The solid solution towers the site symmetry of the lattices in ZrO₂ crystals, which promotes the upconversion efficiency.