反相微乳液法制备EDTA-Tb掺杂SiO_2粒子及其荧光特性

Synthesis And Fluorescence Properties of Terbium(Ⅲ) Chelate-Doped Fluorescent Silica Particles By Reverse Microemulsion Method

用反相微乳法制备了EDTA-Tb掺杂的SiO2荧光粒子。XRD、IR分析表明所得粒子为非晶态,EDTA中的羰基以双齿配位的形式与Tb^3＋配位,荧光粒子中存在Si-OH缺陷。荧光光谱分析表明,在277-396nm之间有一宽而强的Tb^3＋离子的激发谱带,240nm处的最强激发峰是由配体EDTA吸收能量,并将能量传递给Tb^3＋使之发出特征荧光所引起,在240nm光激发下,发射波长位于486nm（5D4-7F6）、544nm（5D4-7F5）、582nm（5D4-7F4）、620nm（5D4-7F3）,掺杂的EDTA-Tb与SiO2摩尔比在1：120-1：15之间时,随着EDTA-Tb的掺杂量的增加SiO2粒子在发射波长为486nm、544nm、582nm、620nm时的最大发射光强度均呈指数增长。

Terbium（Ⅲ） Chelate-Doped Fluorescent Silica particles were synthesized by reverse microemulsion method.XRD and Infrared spectrum analysis shows that the particles were noncrystalline.The coordination forms of carbonyl with Tb^3＋ is double coordination.Fluorescence spectroscopy analysis shows that between 277 and 396 nm,there is a strong and wide-band excitation,the strongest excitation occurred at 240 nm,it was caused by EDTA absorbing energy and the energy was transferred to Tb^3＋ to make it issue features fluorescent. With the 240 nm of light excitation, the emission wavelength appeared at 486 nm（ 5 D4 _-7 F6 ） , 544 nm （ 5 D4 - 7 F5 ） , 582 nm （ 5 D4-7F4） and 620 nm （SD4 -7F3）. Furthermore, when the molar ratio of EDTA -Tb and SiO2 was between 1：120and 1：15, the fluorescence intensity will increase with the concentration of terbium, and the growth is exponential growth.