EDTA络合溶胶-凝胶法制备Y_2O_2S:Eu^(3+),Mg^(2+),Ti^(4+)红色长余辉材料

Synthesis of Red Long Lasting Phosphors Y_2O_2S:Eu^(3+),Mg^(2+),Ti^(4+) by EDTA Complexing Sol-gel Method

采用EDTA(乙二胺四乙酸)络合溶胶-凝胶法制备了Y2O2S:Eu3+,Mg2+,Ti4+粉体。采用X射线衍射仪、扫描电子显微镜和荧光分光光度计对不同温度合成的样品性能进行测试与表征。结果表明:当硫化温度低于1 000℃时,样品为Y2O3与Y2O2S的混合相;当温度在1 050～1 100℃时,样品为纯相的Y2O2S;当温度升高到1 150℃时,再次出现Y2O3的相。硫化温度在950～1 100℃时,产物的粒径为50～300 nm。用波长为330 nm的紫外光激发样品时,626 nm处的发射对应于Eu3+的5D0-7F2跃迁。硫化温度为1 100℃时,样品的余辉时间最佳,为95 min(≥1 mcd/m2)。相比于以乙酰丙酮为络合剂的溶胶-凝胶法,EDTA络合溶胶-凝胶法制备的样品的发光性能具有较大提高。

The red long-lasting phosphor Y2O2S：Eu3＋,Mg2＋,Ti4＋ was synthesized by sol-gel meth- od using EDTA as complexing agent. XRD, SEM and spectra fluorophotometer technique were used to investigate the performance of samples synthesized at different temperatures. When the sulfuretted temperature is below 1 000 ℃, the product is a mixture of Y2O3 and Y2O2S. The pure phase of Y2O2S is obtained when the temperature is 1 050 - 1 100 ~C. When the temperature rises to 1 150 ℃, the phase of Y2O3 appears again. When the temperature is 950 - 1 100 ℃, the size of particle is about 50 ~ 300 nm. From the spetrum, the main emission peak lies at 626 nm under the 330 nm excitation, which is ascribed to the transition of Eu3＋ from 5D0 to 7F2. The optimal afterglow time of the sample is 95 min （≥ 1 mcd/m2） when the sulfurization temperature was 1 100 ℃. Compared with sol-gel method using acetyl acetone as complexing agent, the afterglow properties of samples synthesized by sol-gel method using EDTA as complexing agent have been greatly improved.