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

Synthesis and Luminescent Properties of Novel Ultra-fine Bule Emitting Phosphors Sr_2MgSi_3O_9∶Eu^(2+)

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Sr2MgSi3O9∶Eu2+。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:Sr2-xMgSi3O9∶Eu2x+系列样品的衍射峰数据与Sr2MgSi2O7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100nm左右。激发光谱分布在250～450nm的波长范围,主激发峰位于424nm处,次激发峰位于400nm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470nm附近,是典型的Eu2+的4f5d-4f跃迁导致的。Sr2MgSi3O9∶Eu2+是一种很有前途用于白光LED的蓝色荧光粉。

Novel bule emitting phosphors Sr2MgSi3O9∶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 Sr2MgSi3O9∶Eu^2＋ phosphors possess the similar tetragonal crystal structure as that of Sr2MgSi2O7. 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 Sr2MgSi3O9∶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 Eu2＋ typical transition from 4f 5d to 4f. Sr2MgSi3O9∶ Eu^2＋ shows good prospect for blue phosphors of white LED.