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Updated: Jul 23, 2025

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Low-energy Cathodoluminescence for OxyNitride Phosphors
Published on: November 15, 2016
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在BaFBr:Eu2+储存中,发光特性和X射线诱导的缺陷
Lakshmi Narasimhan Sangeetha1, Arunachalam Lakshmanan1, Vairan Sivakumar2
1Department of Physics, Saveetha Engineering College, Thandalam, India.
概括
合成BaFBr:Eu2+X射线储存,使用化消除了氧污染,显著增强光发光 (PL) 和光刺激发光 (PSL) 以改善X射线检测. /比对PSL至关重要的陷地点产生影响.
科学领域:
- 材料科学 材料科学 材料科学
- 发光的光度是非常的低.
- 固态化学 固态化学
背景情况:
- 与双价欧 (BaFBr:Eu2+) 合的化是用于X射线存储的有希望的材料.
- 优化合成对于增强光发光 (PL) 和光刺激发光 (PSL) 特性至关重要.
研究的目的:
- 研究BaFBr:Eu2+的三种不同合成方法.
- 为了比较F/Br和Eu度对PL和PSL敏感性的影响.
- 为了阐明 BaFBr:Eu2+ 中的光刺激发光机制.
主要方法:
- 固态扩散合成 (食谱I) 和两种以化为基础的合成 (食谱II和III) 在850°C的还原大气中.
- 光发光 (PL) 和光刺激发光 (PSL) 的测量.
- 进行X射线衍射 (XRD),场辐射扫描电子显微镜 (FESEM),能量分散X射线光谱 (EDAX) 和热发光 (TL) 研究.
主要成果:
- 固态扩散导致由于氧污染导致PL/PSL强度较低.
- 化方法消除了氧气,显著提高了PSL的效率.
- 增加的F/Br摩尔比率影响了的间歇性和空位度,分别作为关键孔和电子陷.
- F ((Br-) 的中心被确定为PSL过程中至关重要的.
结论:
- 基于化的合成优于生产高灵敏度的BaFBr:Eu2+X射线储存.
- 氧气污染显著降低了PSL的性能.
- /比和由此产生的缺陷结构 (-中心) 是控制PSL机制和效率的关键因素.
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