Photoluminescence of Tb-doped MgAl-LDHs depending on phase transition caused by annealing

• 作 者: 陈玉凤 鲍垚 余志鹏 杨广超 王肖庆
• 机 构: College of Chemistry Nanchang University,
• 出 处: Journal of Rare Earths
• 发表日期: 2016年01期
• 关键词: annealing surroundings hexagonal layered attributed emissions cubic transformed

This paper presented the photoluminescence of Tb-doped Mg-Al layered double hydroxides(Tb-doped Mg Al-LDHs) depending on phase transition caused by annealing. Tb-doped Mg Al-LDHs structure transformed from hexagonal LDHs, cubic Mg O to spinel Mg Al2O4 phase as temperature varied from 200 to 1000 °C. Emission and excitation spectra of Tb-doped Mg Al-LDHs obviously changed with phase transformation. The emissions of Tb3+ ions attributed to 5D4→7FJ transitions(J=3, 4, 5, 6) were observed in the emission spectra of all the Tb-doped samples. The ratio of(5D4→7F5)/(5D4→7F6) emission intensity, which was sensitive to surroundings of Tb3+ ion, markedly enhanced with temperature rising to 600 from 400 °C. Over 600 °C, the ratio of(5D4→7F5)/(5D4→7F6) intensity tended to decreasing up to 1000 °C. The change concerning the ratio of the(5D4→7F5)/(5D4→7F6) emission intensity might be due to various surroundings of Tb3+ induced by phase transformation.

This paper presents the photoluminescence of Tb-doped Mg-Al layered double hydroxides (Tb-doped Mg Al-LDHs) depending on phase transition caused by annealing. Tb-doped Mg Al-LDHs structure transformed from hexagonal LDHs, cubic Mg O to spinel Mg emissions from Tb 3 + ions attributed to 5D4 → 7FJ transitions (J = 3, 4, 5 The ratio of (5D4 → 7F5) / (5D4 → 7F6) emission intensity, which was sensitive to the surroundings of Tb3 + ion, markedly enhanced with temperature rising to 600 from 400 ° C. Over 600 ° C, the ratio of (5D4 → 7F5) / (5D4 → 7F6) intensity tended to decreasing up to 1000 ° C. The change concerning the ratio of the (5D4 → 7F5) / (5D4 → 7F6) emission intensity might be due to various surroundings of Tb3 + induced by phase transformation.