机械力化学-喷雾干燥法制备球形YAG：Ce粉体及其发光特性

Photoluminescence properties of spherical YAG:Ce powders via mechanochemical-spray-drying method

采用机械力化学-喷雾干燥技术制备球形YAG:Ce粉体。通过XRD、SEM和荧光光谱等分析方法,研究焙烧温度、混悬液浓度、Ce3+掺杂量对粉体的形貌、粒度及发光性能的影响。结果表明,YAG:Ce前驱体为球形,粒径分布在2～10μm之间,经1300℃焙烧处理,形貌由毛团状转变为米团状。焙烧温度超过900℃时,形成YAG单相,并随着温度升高晶粒尺寸增大。随着混悬液浓度的增加,粉体尺寸明显增大,相应的发光性能先增大后减小,当浓度达到0.2mol/L时,发光性能最佳,是由于其不同的光学性能造成的。随着Ce3+掺杂量x增加,粉体的发光强度先增大后减小,当x=0.06时,达到最大值,粉体的发射光波长先红移后蓝移;当x=0.1时,红移达最大值。由于电多极的相互作用,产生Ce3+浓度淬灭效应,其能量传递的临界距离Rc≈1.9nm。

In this paper, spherical YAG ： Ce powders were prepared by mechanochemistry spray drying method. The influences of ealcinating temperature, suspension concentration and （＇e： -doped amount on the morpholo- gy, particle size and luminescence property of as-prepared YAG ： Ce powder were investigated by means of XRD, SEM and spectra of fluorescence. The results show the precursors are spherical with the particle size of 2-101,m, which are calcinated at 1300C, and will be transmogrified from hair-ball shape to rice-ball shape. When the calcinating temperature is above 900C, the single YAG phase occurs and the grain size increases with increasing the temperature. The particle size of powders increases, the corresponding luminescence property first increases and then decreases with tile increase of suspension concentration, and 0.2mol/I. was the optimum concentration, due to tile different optical properties of powders. The luminescence intensity of powders first increase and then decreases with increasing the Cea-doped amount （.r）, and the optimum.r was 0.06. The emission wavelength of powders first red-shifts, then blue-shifts with increasing the Cea＋-doped amount, and the maximum red-shift appears whenx was0.1. （）wing to the interaction of electricmultipole, Ce：＊ concentra- tion quenching effect was produced, and the critical distance （R,） was about 1.9nm.