溶胶-凝胶工艺制备SrTiO_3:Pr,Ce红色荧光粉及其发光性能研究

Synthesis of Ce^(3+) and Pr^(3+)-Codoped SrTiO_3 and Its Luminescence Properties by Sol-Gel Route

通过溶胶-凝胶法结合热处理工艺合成了SrTiO3:Pr3+红色荧光粉,研究了共掺Ce离子及其浓度变化对荧光粉发光强度的影响规律。采用X-射线衍射分析(XRD),傅里叶变换红外光谱(FT-IR)和荧光光谱仪(PL)等测试手段对前驱体及热处理样品的相形成过程、物相组成及样品的发光性能进行了测试与表征。荧光光谱测试发现,热处理样品在615 nm处存在一个强的红色发光峰,可归属于Pr3+的1D2→3H4跃迁:而激发谱则由一个主峰位于348 nm处的宽带激发带和一系列强度较弱的窄峰构成,分别归属于Pr3+的4f-5d带间跃迁和4f-4f(3H4-3PJ,J=0,1,2和3H4→1D2)跃迁过程。对掺杂不同浓度Ce离子制备的共掺SrTiO3:Pr3+,Ce荧光体发光性能的研究结果表明,随着掺杂Ce浓度的增加,荧光体发光强度依次下降,对该现象的相关作用机制进行了讨论。

SrTiO3：Pr3＋ with Ce3＋ addition were prepared by sol-gel route and followed by post-annealing process. The gel and its annealed products were characterized by XRD and FT-IR measurements. The luminescence property of the final phosphor products was studied by photoluminescence （PL） and diffraction reflectance spectra. The results of PL spectra at room temperatures show that the intensity of red emission peak at 617 nm, which could be ascribed to the 1D2→3H4 transition of Pr3＋ ion, decreases with the increase of doped Ce molar at low doping level, and remains at a relative steady level with high doping level above 0.10. The mechanism of decreased red emission efficiency by Ce addition was discussed.