中文摘要：

采用共沉淀法合成油性β-NaY F4：Tb3＋,Yb3＋@β-NaY F4纳米颗粒,通过盐酸酸洗改性处理获得水性β-NaY F4：Tb3＋Yb3＋@β-NaY F4纳米核壳结构。表征了油性/水性纳米颗粒的形貌和量子剪裁近红外荧光发射性能。结果表明：制备的油性/水性β-NaY F3＋3＋4：Tb3＋,Yb纳米颗粒呈球状,油性/水性β-NaY F4：Tb3＋,Yb@β-NaY F4纳米颗粒呈棒状;但水性纳米颗粒的尺寸均小于油性的;水性纳米颗粒在水溶液中具有良好的分散性。水性β-NaY F4：Tb3＋,Yb3＋@β-NaY F4纳米颗粒溶液相比于相同溶液浓度和稀土掺杂浓度的油性β-NaY F4：Tb3＋,Yb3＋@β-NaY F4和水性β-NaY F4：Tb3＋,Yb3＋纳米颗粒溶液,其量子剪裁荧光分别增强了1.6倍和3.4倍。这是由于β-NaY F4隔离层的存在,改性既去除了油酸,又不会在发光中心附近产生缺陷,从而得到了较强的量子剪裁荧光。

英文摘要：

The oleate-capped β-NaYF4：Tb3＋,yb3＋ and β-NaYF4：Tb3＋,yb3＋@β-NaYF4 nanoparticles were prepared by a co-precipitation method. The ligand-free β-NaYFa：Tb3＋,yb3＋and β-NaYF4：Tb3＋,yb3＋@β-NaYF4 water-soluble core-shell nanoparticles were obtained via hydrochloric acid modification. The morphology and near-infrared quantum-cutting fluorescence properties were analyzed. The results show that the prepared oleate-capped/ligand-free β-NaYFa：Tb3＋,yb3＋ and β-NaYFa：Tb3＋,yb3＋@β-NaYF4 nanoparticles are ball-like and rod-like, respectively, and the size of ligand-free nanoparticles is smaller than that of the oleate-capped nanoparticles. The ligand-free nanoparticles can be well dispersed in water. The quantum cutting fluorescence of the ligand-free β-NaYF4：Tb3＋,yb3＋@β-NaYF4 core-shell nanoparticles solution is 1.6 times and 3.4 times greater than that of the oleate-capped β-NaYFa：Tba＋,yb3＋@β-NaYF4 and the ligand-free β-NaYF4：Tba＋,Yb3＋ nanoparticles solution at the same solution concentration and rare-earth doping amount, respectively. The enhancement of quantum-cutting luminescence is due to the presence of beta-NaYF4 shell, the modification removes the oleate ligand and prevents the generation of defects nearby the luminescence centers.