无机溶胶凝胶法合成Sr2MgSi2O7:Eu2+,Dy3+蓝色发光材料

以价格低廉的水玻璃代替TEOS(正硅酸乙酯)作为硅源,分别在丁二酸铵、柠檬酸三铵辅助下,通过离子交换-溶胶凝胶法合成Sr2MgSi2O7:Eu2+,Dy3+蓝色发光材料。用DTA、XRD、荧光光谱等手段对材料进行分析和表征。结果表明:在丁二酸铵或柠檬酸三铵调节下,前驱体干凝胶煅烧到1100℃转变为高纯度的Sr2MgSi2O7相,其产物疏松,颗粒小,不需研磨或稍加研磨便得细粉;激发光谱在250～450 nm之间都存在一个强度较高的激发带,以柠檬酸三铵辅助得到的Sr2MgSi2O7:Eu2+,Dy3+蓝色发光材料发光性能较好,发射峰位于467 nm附近,余辉时间长。此外对溶胶凝胶的形成机理等进行讨论。

Synthesis of blue long-lasting phosphorescent material Sr2MgSi2O7 ：Eu2＋, Dy3＋ by a inorganic sol-gel method

Blue long-lasting phosphorescent materials with high brightness,Sr2MgSi2O7:Eu2+,Dy3+,were prepared by a inorganic sol-gel method using the sodium silicate(Na2SiO3) as the silicon source to replace the high price TEOS.In which the tribasic ammonium citrate and succinate ammonium as a catalyzer controlled the polymerization of sol by adjusting pH value of the system,respectively.The products were characterized by DTA,XRD and fluorescence spectra.The results indicate that both the materials of Sr2MgSi2O7:Eu2+,Dy3+under the assistance of tribasic ammonium citrate or succinate ammonium possess pure phase,tetragonal crystal structure when the xerogel precursor is calcined at 1100 ℃.It is easy to grind the materials into superfine powder.The materials have photoluminescence and long afterglow luminescent behavior.There is higher intensity excitation band at 250-450 nm on its excitation spectrum and the emission peak on its emission spectrum is at 467 nm or so.The luminescent properties of the materials assisted by tribasic ammonium citrate are better than that assisted by succinate ammonium.In addition,the formation mechanism of the colloidal silica sol and gel is discussed.