荧光纳米材料YPO4∶Sm3+@YPO4@聚乙二醇的构筑及其荧光性能

为了改善稀土磷酸盐的疏水性和荧光性能，利用水热和微波的方法构筑了双层荧光纳米材料YPO₄∶Sm³⁺@YPO₄@PEG (PEG为聚乙二醇)。首先通过调控YPO₄∶Sm³⁺与YPO₄的物质的量之比制备不同壳厚的核壳结构纳米发光材料YPO₄∶Sm³⁺@YPO₄，优选能够增强主体荧光性能的最佳物质的量之比。然后选用PEG进行包覆，得到YPO₄∶Sm³⁺@YPO₄@PEG。利用X射线衍射、扫描电子显微镜、透射电子显微镜、傅里叶变换红外光谱和荧光光谱对产物的结构、形貌和荧光性能进行了表征。结果表明：包覆前后的纳米荧光粉都具有单一的四方晶系(YPO₄)结构，呈纳米球型，半径60~100 nm，包覆层的厚度10~20 nm。双层核壳结构的YPO₄∶Sm³⁺@YPO₄@PEG的荧光强度比纳米荧光粉YPO₄∶Sm³⁺增强了6倍多。可见该双层荧光纳米材料不仅具有亲水性和生物相容性，也增强了YPO₄∶Sm³⁺的荧光强度。

Fluorescent Nanomaterial YPO4: Sm3+@YPO4@Polyethylene Glycol: Construction and Fluorescent Properties

In this work, a double-layered fluorescent nanomaterial YPO₄:Sm³⁺@YPO₄@PEG (PEG=polyethylene glycol) was constructed by using hydrothermal and microwave methods, to improve the hydrophobicity and fluorescence properties of rare-earth phosphates. Firstly, the core-shell nano-luminescent material YPO₄:Sm³⁺@YPO₄ was prepared by adjusting the molar ratio of YPO₄:Sm³⁺ and YPO₄ to prepare the core-shell structure with various ratios of core diameter and shell thickness, and the optimal molar ratio was obtained. YPO₄:Sm³⁺@YPO₄@PEG was prepared with PEG as the coating. The structure, morphology, and fluorescence properties of the product were characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope, Fourier transform infrared spectra, and fluorescence spectra. Finally, the results show that the produced nano-phosphor is a singlephase material with a tetragonal unit cell (YPO₄). The product is not affected by the coating; the particles of the material had spherical morphology with a diameter of 60-100 nm, and the thickness of the coating layer was about 10-20 nm. The fluorescence intensity of YPO₄:Sm³⁺@YPO₄@PEG with the double-layered core-shell structure was more than six times stronger than that of nano-phosphor YPO₄:Sm³⁺ without the core-shell structure. In conclusion, the double-layered fluorescent nanomaterial has hydrophilicity and biocompatibility, menanwhile enhanced fluorescence intensity of YPO₄:Sm³⁺.