以Y2O3-Al2O3-SiO2-Li2O-K2O-Na2O玻璃作为Ce,Pr掺杂基质玻璃,制备出白光LED用Ce:YAG和Ce,Pr:YAG微晶玻璃.使用X射线衍射仪、场发射扫描电子显微镜、荧光光度计对微晶玻璃的晶相、微观形貌、光谱性能及荧光寿命进行了研究.结果表明:掺杂铈或铈镨共掺杂的基质玻璃在1400℃热处理得到YAG纯相;Ce:YAG和Ce,Pr:YAG微晶玻璃在466 nm有特征激发峰;在蓝光芯片激发下,Ce:YAG微晶玻璃在480～700 nm产生有效发射,发射光谱中心波长531 nm,铈镨共掺微晶玻璃在609 nm有窄的发射峰,能提高LEDs的显色性.浓度掺杂实验表明镨的较佳掺杂浓度是Ce:Pr为5:6.Ce:YAG和Ce,Pr:YAG微晶玻璃的荧光衰减曲线表明:Ce:YAG微晶玻璃荧光寿命比Ce,Pr:YAG微晶玻璃长.%Using Y2O3-Al2O3-SiO2-Li2O-K2O-Na2O as Ce-doping or Ce, Pr co-doping glass matrix, Ce:YAG and Ce, Pr:YAG glass ceramic for White-LED (WLED) was prepared by heat treatment of the glass matrix. The formation of YAG crystal phase, morphology, luminescence properties and lifetime were examined by X-ray diffraction (XRD), Field-emission scanning electron microscopy. (FE-SEM) and photoluminescence spectroscopy. XRD analysis indicates that pure YAG phase is formed by heat treating at 1 400 ℃. Characteristic excitation peak located at 466 nm is observed in the excitation spectra of the Ce:YAG or Ce, Pr:YAG glass ceramic. A broad emission band from 480~700 nm, centered at 531 nm is produced with blue light excitation. A narrow emission peak is located at 609 nm in Ce, Pr:YAG glass ceramic, which may improve the color rendering index (CRI)of WLED. Different Pr-codoping experiments show that the maximum is achieved with samples doped with the 5=6 (redraft) ratio. Decay curves for the fluorescence of Ce:YAG glass-ceramic test show that the lifetime of the Ce:YAG glass ceramic is longer than that of the Ce, Pr:YAG glass ceramic.
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