摘要
采用水热法制备了白色长余辉微纳米发光材料Y2O2S∶x Dy3+,Mg2+,Ti4+(x=0.5%,1.0%,1.5%,2.0%,2.5%),利用X射线粉末衍射(XRD)、扫描电镜(SEM)、激发和发射光谱、色度坐标、余辉曲线和热释光谱对样品进行表征。结果表明:煅烧后,样品的形貌为颗粒状,其粒径在150~250 nm之间;在359 nm的紫外光激发下,样品在488 nm和579 nm处有两个很强的发射峰,它们分别对应于Dy3+的蓝色跃迁(4F9/2→6H15/2)和黄色跃迁(4F9/2→6H13/2),适当比例的黄光和蓝光混合可以产生白光;当Dy3+浓度为2.0%(摩尔分数)时,样品的余辉性能最佳,用254 nm的低压汞灯照射10 min后,余辉时间可达到3600 s(≥1 mcd/m2)以上,与同样温度下高温固相法或溶胶凝胶法所制备样品的相比,其余辉性能得到了很大改善。
White-luminescent materials with long afterglow Y_2O_2S：Dy^3＋,Mg^2＋,Ti^4＋ （x = 0.5% , 1. 0% ,1.5%, 2. 0%, 2. 5% ）were synthesized at low temperature via the hydrothermal method. The samples were characterized by the powder X-ray diffraction （XRD）, scanning electron microscopy （SEM）, photoluminescence（ PL）, afterglow decay curves and the thermoluminescence（TL） curves. The results show that the morphology of samples are granular and the diameter of particles are about 150-250 nm. Under 359 nm UV excitation, there are two sharp emission peaks at 488 nm and 579 nm which corresponded to the transitions from ^4F_9/2 to ^6H_15/2 level and ^4F_9/2 to ^6H_13/2 level of Dy^3＋ , respectively, according to the suitable control of the blue and yellow intensity ratio, the white-light can be obtained; when the concentration of Dy^3＋ reached 2.0% , the sample show the optimal initial luminance and afterglow time, the decay time could last for over 3600 s （≥ 1 mcd/m^2 ） after irradiation with 254 nm UV （Ultraviolet） radiation for 10 min. The luminescent performance of the sample is better than which obtained by the solid state or sol-gel method at the same temperature.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2015年第2期354-360,共7页
Journal of Synthetic Crystals
基金
国家自然科学基金(51072128)
山西省科技攻关项目(20110321040-01)
山西省自然科学基金(2014011017-3)
