冷白光荧光粉ZnWO_4∶Sm^(3+)的制备及发光性质

Preparation and Luminescence Properties of Cold White Light-emitting Phosphors ZnWO_4∶Sm^(3+)

采用水热法经过煅烧热处理成功制备了ZnWO4∶Sm3+白色荧光粉。通过X射线粉末衍射仪,扫描电子显微镜及荧光分光光度计对样品的物相结构、形貌粒度及发光性能进行了分析和表征。结果表明:在pH值为6和7下,所合成的Zn WO4∶Sm3+晶体结构与Zn WO4相似,为单斜晶系结构,样品颗粒为类球形,颗粒尺寸范围为100~220nm。Sm3+的摩尔掺杂量为0.5%时,发射峰强度达到最大值;继续增加Sm3+浓度,其发射峰强度反而减弱,出现了浓度猝灭效应。在254 nm波长激发下,ZnWO4∶Sm3+的色坐标集中在冷白光区。

ZnWO4∶ Sm3＋ white phosphors were prepared via hydrothermal process with further heat treatment. The phase structure,morphology and luminescent properties of the samples were characterized by X-ray diffraction（ XRD）,scanning electron microscope（ SEM） and fluorescence spectrophotometer,respectively. The results indicate that the crystal structure of as-synthesized ZnWO4∶ Sm3 ＋is similar to the pure monoclinic Zn WO4 under the p H value of 6 and 7. These samples are approximately spherical particles with the particles size from 100 to 220 nm. When the concentration of Sm3 ＋is 0. 5%,the intensity of emission peak reaches the maximum. The concentration quenching occurs when Sm3 ＋concentration is beyond 0. 5%. Under 254 nm excitation,the chromaticity coordinates are located in cold white light zone.