采用微乳液法制备了BaYF5Eu2+纳米微粒，并利用X射线衍射（XRD）、扫描电子显微镜（SEM）和光致发光光谱等手段进行了表征。XRD数据与标准卡片PDF # 46-39很好吻合,利用谢乐公式计算所制备产物平均粒径在20 nm左右。SEM图谱显示所制备的纳米粒子为球形，且形貌规则，粒径分布比较均匀。BaYF5Eu2+的发射光谱中存在一个300~410 nm的发射带，发射光谱最强峰为330 nm，对应于Eu2+的4f65d→4f7发射，与传统高温固相法所制多晶材料最强发射峰378 nm相比蓝移了48 nm；其激发光谱最强峰位于263 nm，与传统高温固相法所制多晶材料最强激发峰322 nm相比蓝移了59 nm。

Eu2+-doped BaYF5 nanoparticles are prepared via microemulsion method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence spectroscopy are used to characterize the samples. The results of XRD are in agreement with the PDF # 46-39 of BaYF5, and the average size is about 20 nm estimated by Scherrer formula. The SEM images show that the nanoparticles are spheric morphology, while the shape is regular and the particle size is homogeneous. The emission band of BaYF5Eu2+ nanoparticles locate in the range of 300~410 nm. The predominant peak corresponding to the 4f65d→4f7 transition of Eu2+ locates at 330 nm, which exhibites a blue shift of 48 nm compared with that of the polycrystalline materials prepared by traditional solid-state reaction that centers at 378 nm. The main excitation peak locates at 263 nm, which shows a blue shift of 59 nm compared with that of the polycrystalline materials that centers at 322 nm.