不同分散剂对制备YAG:Ce^(3+)荧光粉结构和性能的影响

Effect of Different Dispersant on Structure and Properties in YAG:Ce^(3+) Phosphor Synthesized

分别用乙二醇和聚乙二醇作为分散剂,采用络合凝胶法合成YAG∶Ce3+荧光粉.利用X射线衍射仪、扫描电子显微镜、荧光分光光度计对合成的荧光粉进行分析.XRD图谱显示所有的荧光粉均为立方相.采用Scherrer公式分别计算以乙二醇和聚乙二醇为分散剂制备的荧光粉的平均粒径:27.1 nm和25.0 nm.发射光谱的发射峰为530 nm处的一个宽带发射峰,对应的是Ce3+离子5d→4 f跃迁;激发光谱有2个激发峰,分别位于345 nm和470 nm,对应的是Ce3+离子2F5/2→5d和2F7/2→5d的跃迁.光谱研究结果表明:采用乙二醇制备的样品的发光相对强度大于用聚乙二醇制备的样品的发光相对强度.

YAG： Ce^3＋ phosphors have been synthesized by using a complex sol-gel method, in which ethylene glycol or polyethylene glycol was used as dispersant. YAG： Ce^3＋ phosphors were studied by Xray diffraction, scanning electron microscopy and fluorescence spectrophotometer. The results of XRD showed that all of the samples were in the pure cubic phase. By applying the Scherrer formula and calculating, the average crystallite size of the phosphors was 27.1 nm and 25.0 nm when ethylene glycol and polyethylene glycol was used as a dispersant, respectively. The broad emission peak was located at 530 nm attributed to 5d→4f transition of Ce^3＋ ions. The excitation spectra had two excited peaks at 345 nm and 473 nm attributed to 2F5/2→5d transition and 2F7/2→5d transition of Ce^3＋ ions. It was shown from the spectra that the intensities of luminescence of the sample prepared by using ethylene glycol as a dispersant was stronger than that of polyethylene glycol as a dispersant.