摘要
采用凝胶-燃烧法,在活性炭弱还原气氛下合成了新型荧光粉Sr3-xMgSi3O10∶Tb3x+,通过热分析仪、红外光谱、X射线粉末衍射、X射线能量色散谱仪及荧光分光光度计等对产物的形成过程、结构、组成及发光性质进行了分析和表征。结果表明:干凝胶起火燃烧得前驱物,经900℃还原热处理即可得目标产物,其晶体结构与Sr2MgSi2O7相似,同属四方晶系。Sr3-xMgSi3O10∶Tb3x+的激发光谱为一位于200～300nm的宽带,主激发峰在249nm左右;发射光谱由491nm,544nm,586nm,624nm等一系列窄带发射峰组成,归属于Tb3+的5D4到7FJ(J=6,5,4,3)的跃迁。主发射峰位于544nm,对应于Tb3+的5D4→7F5的能级跃迁,导致一种黄绿光发射。研究发现:还原温度及Tb3+掺杂浓度对发光强度有着重要的影响,并对浓度猝灭机制进行了探讨。
Novel rare earth luminescent materials Sr3-xMgSi3O10∶ Tb3x ＋were synthesized by gel-combustion method in activated carbon weak reductive environment. The formation process,phase structure,composition and luminescent properties of the as-synthesized phosphors were investigated by TG-DTA,infrared spectroscopy,X-ray powder diffraction,Energy Dispersive Spectrometer and Fluorescence spectrophotometer. The results show that Sr3-xMgSi3O10∶ Tb3＋ phosphors possess the similar tetragonal crystal structure with Sr2MgSi2O7. The excitation spectrum of Sr3-xMgSi3O10∶ Tb3x ＋has a broad band from 200 nm to 300 nm,and the main peak is at 249 nm. The emission spectrum is composed of a series of peaks,located respectively at 491 nm,544 nm,586 nm,624 nm. These emission peaks are ascribed to Tb3＋ transition from 5D4 to 7FJ（ J =6,5,4,3）. The main emission peak is at 544 nm due to the transition of 5D4→7F5,which results in a yellow-green emitting. In addition,it is found that the reductive temperature and the concentration of doped Tb3＋ have great effects on the luminescent intensity of the sample,and the mechanism of concentration quenching was discussed.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2010年第4期906-911,共6页
Journal of Synthetic Crystals
基金
国家自然科学基金资助项目(No.20675023)
