采用高温熔融法制备了一种新型的Ce3 +/Tb3+共掺BaYF5微晶玻璃.测试了微晶玻璃的X射线衍射图(XRD)谱、激发光普和发射光谱.研究发现:660℃热处理2h后的玻璃基质中析出BaYF5纳米晶相,根据XRD结果用Scherrer公式计算得到晶粒大小约为27 nm；在近紫外光(338 nm)激发下,观察到BaYF5微晶玻璃宽带蓝光(425 nm)发光对应Ce3的5d→2F5/2和5d→2F7/2能级跃迁,蓝光(487 nm)、绿光(541 nm)、橙光(582 nm)和红光(620 nm)发光对应于Tb3+的5D4→7FJ(J=6,5,4,3)能级跃迁.通过调节Ce3+和Tb3+的掺杂浓度,得到色坐标为(0.287,0.336)的白光发光微晶玻璃,并系统分析了Ce3+和Tb3+离子的发光机理和能量传递过程.研究结果表明:Ce3 +/Tb3+共掺的BaYF5微晶玻璃是制作白光LED的一种潜在基质材料.%A new Ce3 +/Tb3 + co-doped BaYF5 glass ceramic was prepared by high temperature melting. The X-ray diffraction spectra, excitation spectra and emission spectra were measured. The results indicate the BaYF5 nanocrystalline phase exists in the glass matrix. Based on the Scherrer equation, the average size about 27 nm of BaYF5 nanocrystalline was calculated. The intense blue emission band (425 nm) assigned to 5d→2F5/2 and 5d→2F7/2 transitions of Ce3 + and blue emission(487 nm) , green emission (542 nm) , orange emission (582 nm) and red emission (620 nm) assigned to 5D4→7FJ(J =6,5,4,3) transitions of Tb 3 + ions, respectively, were observed at room temperature under 338 nm excitation in the glass ceramics. By adjusting the doped concentration of Ce3 + and Tb3 + , the chromaticity coordinate of the glass ceramic is measured to be (0. 287, 0. 336). The energy transfer between Ce 3 + and Tb 3 + was analysised systematically. The results indicate that Ce3 + / Tb3 + co-doped BaYF5 glass ceramics is a potential matrix material for white LED.
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