采用共沉淀法制备了一系列Al2O3含量由低到高的ZrO2-Al2O3固溶体, 并研究了固溶体的晶相结构以及稀土Er3+在固溶体中的上转换发光增强机制。 XRD结果表明固溶体为四方晶相ZrO2结构, Al2O3的最高固溶度约为20 mol%。 上转换发光光谱分析表明, Er3+掺杂ZrO2室温下具有绿色上转换荧光发射, 通过共掺杂Yb3+和Mo6+离子, 使得Er3+掺杂ZrO2的绿色上转换发光强度增强了约20倍, 获得了明亮的黄绿色上转换发光。 基质ZrO2通过与Al2O3固溶形成复合氧化物, 由于产生的大量氧空位缺陷的能级与Er3+的4F7/2能级高度相接近, 增强了Yb3+-MoO2-4基团(2F7/2, 3T2)能级向Er3+的4F7/2能级的能量传递。 通过形成固溶体复合氧化物基质材料, 使得Er3+的绿色上转换发光在获得20倍增强的基础上又提高了8倍。 绿色与红色上转换发光比例的变化也提高了材料的色纯度, 上转换发光由黄绿色变为纯绿色。

A series of ZrO2-Al2O3 composites with various compositions were synthesized by co-precipitation method, and the upconversion emission properties of the Er-Yb-Mo co-doped ZrO2-Al2O3 composites were investigated in the present paper. The green UC emission in the Er-Yb-Mo co-doped ZrO2 is an order of magnitude stronger than that of the Er3+ single doped sample. When Al2O3 mixed in ZrO2 crystalline lattice with the most solid solubility, the crystalline ZrO2-Al2O3 solid solutions is tetragonal ZrO2. The UC emission is enhanced 8 times in the ZrO2-Al2O3 solid solutions, which is due to the oxygen vacancies generated in the solid solutions, increasing the energy transfer from Yb3+-MoO2-4 to Er3+.