期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
Photoluminescence of Tb-doped MgAl-LDHs depending on phase transition caused by annealing 被引量:1
1
作者 陈玉凤 鲍垚 +2 位作者 余志鹏 杨广超 王肖庆 《Journal of Rare Earths》 SCIE EI CAS CSCD 2016年第1期36-44,共9页
This paper presented the photoluminescence of Tb-doped Mg-A1 layered double hydroxides (Tb-doped MgAI-LDHs) depending on phase transition caused by annealing. Tb-doped MgA1-LDHs structure transformed from hexagonal ... This paper presented the photoluminescence of Tb-doped Mg-A1 layered double hydroxides (Tb-doped MgAI-LDHs) depending on phase transition caused by annealing. Tb-doped MgA1-LDHs structure transformed from hexagonal LDHs, cubic MgO to spinel MgA1204 phase as temperature varied from 200 to 1000 ℃. Emission and excitation spectra of Tb-doped MgAI-LDHs obviously changed with phase transformation. The emissions of Tb3+ ions attributed to 5D4→TFJ transitions (J=3, 4, 5, 6) were observed in the emission spectra of all the Tb-doped samples. The ratio of (SD4→7F5)/(SD4→7F6) emission intensity, which was sensitive to surroundings of Tb3+ ion, markedly enhanced with temperature rising to 600 from 400 ℃. Over 600 ℃, the ratio of (SD4→TF5)/ (SD4→TF6) intensity tended to decreasing up to 1000 ℃. The change concerning the ratio of the (SD4→7F5)/(SD4→TF6) emission intensity might be due to various surroundings of Tb3+ induced by phase transformation. 展开更多
关键词 mgai-ldh Tb-doped phase transition PHOTOLUMINESCENCE ANNEALING rare earths
原文传递
MgAl-LDH强化Bi单质等离子体光催化性能的机制 被引量:2
2
作者 吕晓书 曹嘉真 +3 位作者 李欣蔚 曹继武 张贤明 董帆 《科学通报》 EI CAS CSCD 北大核心 2018年第25期2620-2630,共11页
通过液相超声辅助组装的方式将铋纳米球(Bi-NPs)均匀负载于层状氢氧化镁铝(MgAl-LDH)纳米片上,成功合成Bi@MgAl-LDH复合光催化剂.该催化剂在光照射下,可通过Bi单质等离子体效应连续高效氧化空气中ppb(十亿体积气体中所含污染物体积)浓... 通过液相超声辅助组装的方式将铋纳米球(Bi-NPs)均匀负载于层状氢氧化镁铝(MgAl-LDH)纳米片上,成功合成Bi@MgAl-LDH复合光催化剂.该催化剂在光照射下,可通过Bi单质等离子体效应连续高效氧化空气中ppb(十亿体积气体中所含污染物体积)浓度量级的NO(去除效率可稳定在56%).采用X射线衍射仪(XRD)、电子扫描显微镜(SEM)和紫外可见漫反射光谱(UV-visDRS)等手段对催化剂物相、形貌、化学组成和光学性质进行了表征分析,结合电子顺磁共振(ESR)氧化自由基捕获实验并采用原位红外光谱技术对光催化氧化NO过程进行动态监测发现,虽然MgAl-LDH作为载体没有与Bi球形成异质结结构,但其表面富含丰富的氢氧根离子,能与Bi球上光激发产生的空穴快速结合,形成·OH自由基;而光生空穴的快速消耗又能降低其与光生电子的复合,增强光电分离,促进超氧自由基形成,通过这两方面的协同作用增强了Bi球对NO的光催化氧化效果.更重要的是,LDH具有独特的水分子记忆效应,在光催化过程中被消耗的氢氧根离子可通过吸附空气中水分而不断补充,促使催化活性的稳定高效.本文的研究结果为Bi单质基等离子体直接光催化降解气相污染物性能强化提供了新的策略,同时对光催化反应机制的研究提出了新的思路. 展开更多
关键词 Bi单质 表面等离子体效应 MgAl-ldh 光催化 原位红外光谱
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部