NaYF_4:Yb,Er上转换荧光纳米颗粒的合成及表面修饰

Synthesis and Surface Modification of NaYF_4:Yb,Er Upconversion Fluorescent Nanoparticles

以稀土硬脂酸盐为前驱体,利用热分解法在液体石蜡-油酸体系中合成出具有较高发光强度的NaYF4∶Yb,Er上转换荧光纳米颗粒.通过透射电子显微镜(TEM)、X射线衍射(XRD)、红外光谱(FT-IR)以及荧光光谱对纳米颗粒进行了表征,推断出该合成反应的机理为固-液两相反应.详细探讨了反应时间、温度以及溶剂组成对纳米颗粒荧光性能的影响.通过Lemieux-von Rudloff试剂将包覆有油酸分子的纳米颗粒表面羧基化修饰,使纳米颗粒具有良好的水溶性.

NaYF4 ： Yb, Er upconversion nanoparticles with strong fluorescent intensity were synthesized in the liquid paraffin-oleic acid system via a thermolysis method, with the rare earth stearate used as precursor. The as-prepared nanoparticles were characterized by TEM, XRD, FT- IR and luminescence spectroscopy. It was inferred that the mechanism of the synthesis is of a solid-liquid two-phase reaction. The effects of reaction time, temperature and solvent composition on the fluorescent performance of the nanoparticles were discussed in detail. As a result, the oleic acid-coated hydrophobic nanoparticles became highly hydrophilic after their surfaces were modified with carboxylic groups by use of the Lemieux-von Rudloff reagent.