Department of Electrical Engineering, National University of Tainan, Tainan City, Taiwan.
Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung, Taiwan.
Luminescence. 2021 Feb;36(1):20-27. doi: 10.1002/bio.3910. Epub 2020 Jul 15.
In this study, Eu-doped Li (Ba Sr )SiO powders (x = 0, 0.2, 0.4, and 0.6) were synthesized at 850°C in a reduction atmosphere (5% H + 95% N ) for a duration of 1 h using a solid-state reaction method. The reduction atmosphere was infused as the synthesis temperature reached 850°C, and was removed as the temperature dropped to 800-500°C. Li (Ba Sr )SiO (or Li BaSiO ), (Ba,Sr) SiO (or BaSiO ), and Li SiO phases co-existed in the synthesized Eu-doped Li (Ba Sr )SiO powders. A new finding was that the reduction atmosphere removing (RAR) temperature of the Li (Ba Sr )SiO phosphors had a large effect on their photoluminescence excitation (PLE) and PL properties. Except for the 800°C-RAR-treated Li BaSiO phosphor, PLE spectra of all other Li (Ba Sr )SiO phosphors had one broad emission band with two emission peaks centred at ~242 and ~283 nm; these PL spectra had one broad emission band with one emission peak centred at 502-514 nm. We showed that the 800°C-RAR-treated Li BaSiO phosphor emitted a red light and all other Li (Ba Sr )SiO phosphors emitted a green light. Reasons for these results are discussed thoroughly.
在这项研究中，Eu 掺杂的 Li（Ba Sr ）SiO 粉末（x = 0,0.2,0.4 和 0.6）在 850°C 的还原气氛（5%H + 95%N ）中通过固态反应法合成 1 小时。当合成温度达到 850°C 时，注入还原气氛，当温度降至 800-500°C 时，去除还原气氛。在合成的 Eu 掺杂的 Li（Ba Sr ）SiO 粉末中，共存 Li（Ba Sr ）SiO（或 Li BaSiO ）、（Ba,Sr）SiO（或 BaSiO ）和 LiSiO 相。一个新的发现是，Li（Ba Sr ）SiO 荧光粉的还原气氛去除（RAR）温度对其光致发光激发（PLE）和 PL 性质有很大影响。除了 800°C-RAR 处理的 Li BaSiO 荧光粉外，所有其他 Li（Ba Sr ）SiO 荧光粉的 PLE 光谱都有一个宽发射带，两个发射峰中心位于242nm 和283nm；这些 PL 光谱有一个宽发射带，一个发射峰中心位于 502-514nm。我们表明，800°C-RAR 处理的 Li BaSiO 荧光粉发射红光，而所有其他 Li（Ba Sr ）SiO 荧光粉发射绿光。讨论了这些结果的原因。
