2018年9期电子期刊

采用高温固相法在1 150℃下经二次煅烧合成了双钙钛矿型的红色荧光粉Sr₂ZnTeO₆∶xEu³⁺（x=0.05-0.40），并进行了相组成、发光性质和热稳定性的研究。结果表明，所合成的Sr₂ZnTeO₆与Sr₂ZnWO₆具有相同的结构，掺杂离子的加入没有改变相结构。样品的激发光谱由电荷迁移带和Eu³⁺离子的特征激发峰组成，主激发峰位于464 nm（⁷F₀→⁵L₆）。样品的发射光谱位于614 nm（⁵D₀→⁷F₂）。Sr₂ZnTeO₆∶xEu³⁺荧光粉的发光强度随着Eu³⁺离子的掺杂，先增大后减小，在x≥0.25时，发生浓度猝灭现象。通过变温荧光发现它具有非常好的热稳定性。由于荧光粉的最佳激发位于464 nm，因而可以用于蓝光激发下的白光LED的红色荧光粉。

Synthesis and Luminescence Properties of Red-emitting Sr2ZnTeO6: Eu3+ Phosphors

A series of novel double perovskite tellurate red-emitting phosphors Sr₂ZnTeO₆:xEu³⁺(x=0.05-0.40) were successfully synthesized by a high-temperature solid-state reaction method at 1 150℃. The phase structure, photoluminescence properties and thermal stability of the phosphor were investigated in detail. The phosphor shows dominant emission peak at 614 nm belonging to the ⁵D₀→⁷F₂ electric dipole transition under 464 nm excitation. The luminescence intensity keeps increasing with increasing the content of Eu³⁺ to 25%, and the critical transfer distance of Eu³⁺ was calculated to be 1.2 nm. The quenching temperature for Sr₂ZnTeO₆:0.25Eu³⁺ was estimated to be above 500 K. This spectral feature reveals high color purity and excellent chromaticity coordinate characteristics. Therefore, Eu³⁺-doped Sr₂ZnTeO₆ phosphors are potential red phosphors for blue chip-based white light-emitting diode and display devices.