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Updated: Jul 5, 2025
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Low-energy Cathodoluminescence for OxyNitride Phosphors
Published on: November 15, 2016
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2+和欧3+对强白石中发光的共效应
Ivan V Nikiforov1, Dmitry A Spassky2,3, Nataliya R Krutyak2,3
1Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia.
Molecules (Basel, Switzerland)
|January 11, 2024
概括
合成了含有和欧的新型基于的酸盐. 研究人员观察到欧的异常减少,并分析了其光发光特性,发现会灭欧排放.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
- 固态化学 固态化学
背景情况:
- 酸因其独特的结构和发光特性而受到研究.
- 斯特伦白石,一种β-三酸的多态,作为一个有前途的宿主格子.
- 用稀土元素 (如欧) 进行兴奋剂可以诱导发光,而过渡金属 (如) 可以作为火剂或联合激活剂.
研究的目的:
- 合成和描述一系列新的基于酸的酸盐,特别是酸9-xMnxEu(PO4) 7.7.
- 研究结构阶段和空气中Eu3+异常减少为Eu2+的情况.
- 研究这些材料的光发光特性,包括Mn2+度对Eu3+发光的影响以及Eu2+发射的温度依赖性.
主要方法:
- 在空气中高温固态合成.
- 用X射线衍射 (XRD) 来进行相位识别和结构分析.
- 光发光 (PL) 谱学用于研究Eu2+和Eu3+的辐射.
- 电子自旋共振 (ESR) 谱学以确认Eu2+的存在.
主要成果:
- 一系列新的Sr9-xMnxEu(PO4)7化合物已成功合成,其结构为白洛克 (β-Ca3(PO4) 2).
- 在空气中观察到Eu3+部分降低到Eu2+,这得到了PL和ESR的证实.
- 光发光光谱显示了在370nm激发下来自Eu2+ (4f5d-4f) 和Eu3+ (4f-4f) 的排放.
- 由于火,Mn2+度的增加导致395nm的Eu3+排放强度下降.
- 研究了Eu2+光发光的温度依赖性.
结论:
- 合成的Sr9-xMnxEu(PO4)7化合物表现出一种强的白色洛克结构.
- 存在Mn2+会影响Eu3+降解为Eu2+并灭Eu3+的发光.
- 这些材料显示出需要可调节发光的应用的潜力,而Eu2+的排放取决于温度.
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