新型超细蓝色荧光粉Sr_2MgSi_3O_9: Eu~(2+)的合成及发光性质

采用凝胶-燃烧法在活性炭弱还原气氛下成功合成了新型蓝色发光材料Sr_2MgSi_3O_9∶ Eu~(2+).用X射线粉末衍射仪(XRD)、扫描电镜(SEM)、荧光分光光度计等对样品的物相结构、微观形貌及发光性质进行了分析和表征.结果表明:Sr_(2-x)MgSi_3O_9∶ Eu_x~(2+)系列样品的衍射峰数据与Sr_2MgSi_2O_7的JCPDS卡片(卡号:75-1736)衍射峰数据基本一致,属四方晶系.其一次颗粒近似球形,粒径在100 nm左右.激发光谱分布在250～450 nm的波长范围,主激发峰位于424 nm处,次激发峰位于400 nm处,可以被InGaN管芯产生的紫外辐射有效激发.发射光谱也为一宽带,最大发射峰位于470 nm附近,是典型的Eu~(2+)的4f 5d-4f跃迁导致的.Sr_2MgSi_3O_9∶ Eu~(2+)是一种很有前途用于白光LED的蓝色荧光粉.

Synthesis and Luminescent Properties of Novel Ultra-fine Bule Emitting Phosphors Sr2MgSi3O9: Eu2+

Novel bule emitting phosphors Sr_2MgSi_3O_9∶Eu~(2+) was synthesized by gel-combustion method in weak reductive environment.The phase structure, microstructure and luminescent properties of the as-synthesized phosphors were investigated by XRD, SEM and fluorescence spectrophotometer. The results showed that Sr_2MgSi_3O_9∶Eu~(2+) phosphors possess the similar tetragonal crystal structure as that of Sr_2MgSi_2O_7 . The initial particles of the phosphors are nearly spherical in shape, and the grain size is about 100 nm in diameter. The excitation spectrum of Sr_2MgSi_3O_9∶Eu~(2+) is a broad band in the range of 250-450 nm,the main peak is at 424 nm and the secondary peak is at 400 nm, which can be excited efficiently by UVLED chip whose emission peak locates at 360-400 nm. The emission spectrum is also a broad band, the emission peak is at about 470 nm. It's ascribed to Eu~(2+) typical transition from 4f 5d to 4f.Sr_2MgSi_3O_9∶Eu~(2+) shows good prospect for blue phosphors of white LED.