目前使用的白光LEDs荧光粉, 主要是适于蓝光GaN芯片激发的黄、 绿、 红色稀土荧光粉。 黄、 绿光荧光粉技术已经相对完善, 而发光良好、 性能稳定的红色荧光粉比较少。 因此, 需要开发新型的蓝光激发型红色荧光粉。 相对于传统的高温固相法制备荧光粉体, 本文利用水热法在较低温度160　℃成功制备出了发光性能良好的单分散球形钨酸钙红色发光材料CaWO4∶Sm3+和CaWO4∶Eu3+。 通过X射线粉末衍射仪(XRD)、 场发射扫描电镜(FE-SEM) 、 荧光光谱仪(PL)等表征手段, 研究了所制备材料的晶体结构、 表面形貌以及光学特性。 讨论掺杂稀土离子浓度、 反应时间等条件的改变对样品形貌以及发光性能的影响。 结果显示, 掺杂浓度不仅影响材料的形貌, 还影响其发光强度。 当Sm3+和Eu3+掺杂量分别为6%和4%时, CaWO4∶Sm3+和CaWO4∶Eu3+材料的发光性能最优。 研究结果表明, Sm3+和Eu3+掺杂的CaWO4材料可以作为荧光灯和蓝光芯片LED用荧光粉的备选材料。

The white LEDs phosphor used currently mainly are blue GaN chip which excites yellow, green, and red earth phosphor. The technology of yellow and green phosphor has been mature, while red phosphor with stable performance is relatively rare. Therefore, a new type of red phosphor excited by blue light needs to be developed. In this paper, compared with the traditional high temperature solid-phase synthesis method, a series of efficient spherical monodisperse calcium tungstate red luminescent materials CaWO4∶Sm3+ and CaWO4∶Eu3+ with high luminescent performance were synthesized with hydrothermal method at lower temperatures 160 ℃. The crystal structure, surface topography and optical characteristics of the prepared samples were measured with X-ray powder diffraction (XRD), field emission scanning electron microscope (FE-SEM), and fluorescence spectroscopy (PL). The effect of the doping concentration, reaction time and other conditions on the morphology and fluorescence properties of the samples had been studied. The results show that doping concentration affects not only the morphology of the prodcucts, but also the fluorescence intensity of light-emitting phosphor.CaWO4:Sm3+ and CaWO4∶Eu3+ present the most efficient light-emitting performance when the doping concentration of the Sm3+ and Eu3+ are 6% and 4%, respectively. According to the results above, CaWO4∶Sm3+ and CaWO4∶Eu3+ can be used as a phosphor materials of fluorescent lamp and blue chip LED.