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采用聚乙烯吡咯烷酮(PVP)辅助水热法合成了GdF3∶Eu3+和NaGdF4∶Eu3+发光粉。利用X射线衍射(XRD)、扫描电子显微镜和荧光光谱对样品的结构、形貌和发光性能进行了研究。XRD分析表明:GdF3晶相到NaGdF4晶相的转换可以通过改变初始溶液pH值、PVP加入量和NaF与稀土离子(Gd3+和Eu3+)摩尔配比等合成条件实现。NaGdF4∶Eu3+发光粉的形貌受合成条件的影响。荧光光谱研究表明:GdF3∶Eu3+发光粉主发射峰位于593nm处,来自于Eu3+的5 D0→7 F1磁偶极跃迁;NaGdF4∶Eu3+发光粉主发射峰位于616nm,来自于Eu3+的5 D0→7 F2电偶极跃迁。2个样品中Gd3+与Eu3+离子之间存在较好的能量传递,而NaGdF4晶格更有利于2种离子的能量传递。
GdF3:Eu3 + and NaGdF4:Eu3 + luminescent powders were synthesized by hydrothermal method with polyvinylpyrrolidone (PVP). The structure, morphology and luminescent properties of the samples were investigated by X-ray diffraction (XRD), scanning electron microscopy and fluorescence spectroscopy. XRD analysis showed that the conversion of GdF3 phase to NaGdF4 phase can be achieved by changing the pH value of the initial solution, adding PVP and molar ratio of NaF to rare earth ions (Gd3 + and Eu3 +). The morphology of NaGdF4: Eu3 + luminescent powder is affected by the synthesis conditions. Fluorescence spectra showed that the main emission peak of GdF3:Eu3 + luminescent powder was at 593 nm, which was from the 5 D0 → 7 F1 magnetic dipole transition of Eu3 +. The main emission peak of NaGdF4:Eu3 + luminescent powder was at 616 nm, from 5 D0 → 7 F2 electric dipole transition. There is a good energy transfer between Gd3 + and Eu3 + ions in two samples, while the lattice of NaGdF4 is more conducive to the energy transfer of the two ions.