GdPO_(4)·nH_(2)O∶Eu^(3+)发光粉的水热合成及发光性能研究

Hydrothermal synthesis and luminescence properties of GdPO_(4)·nH_(2)O∶Eu^(3+)phosphors

采用水热法制备系列GdPO_(4)·nH_(2)O∶Eu^(3+)发光粉,通过X射线衍射(XRD)、扫描电子显微镜(SEM)、荧光光谱等分析方法对样品的结构、形貌和发光性能进行表征。研究了初始溶液pH、水热反应温度和反应时间等对发光粉的结构和发光性能的影响。XRD和SEM分析结果表明,合成的样品均为六方结构的GdPO_(4)·nH_(2)O,发光粉均为棒状形貌。pH对GdPO_(4)·H_(2)O∶Eu^(3+)的结构和形貌有一定影响。激发光谱研究结果表明,激发带主要来自于Eu-O的电荷迁移带,发射光谱的主发射峰来自于~5D_0→^(7)F_(1)磁偶极跃迁。不同pH条件下合成的样品,由于Eu^(3+)离子周围局域环境的不同而导致电荷迁移带和发射峰相对强度有所不同。水热反应温度和时间也影响Eu^(3+)离子的周围局域环境。

A series of GdPO_(4)·nH_(2)O∶Eu^(3+)phosphors were prepared by hydrothermal method.The structure,morphology and luminescence properties of the samples were characterized by X-ray diffraction,scanning electron microscopy and fluorescence spectroscopy.The effects of pH values of initial solution,hydrothermal reaction temperature and reaction time on the structure and luminescence properties of phosphors were studied.The results of XRD and SEM indicated that the synthesized samples were all hexagonal structured GdPO_(4)·nH_(2)O and the phosphors were all rod-shaped.The pH value of initial solution had a certain effect on the structure and morphology of GdPO_(4)·nH_(2)O∶Eu^(3+).The excitation spectra showed that excitation band originated from change transfer band of Eu-O,and the main emission peak was from 5D0→^(7)F_(1) magnetic dipole transition.The change transfer bands and relatively luminescence intensity patterns of emission were different for the samples synthesized under different initial pH conditions due to the different local environment around Eu^(3+)ions.The temperature and time of hydrothermal reaction also affected the local environment around Eu^(3+)ions.