在添加的CrX3 (X = Cl, Br, I) 范德瓦尔斯化合物中发光和共振
Thom J Snoeren1, Kimo Pressler1, Kyle T Kluherz1,2
1Department of Chemistry, University of Washington, Seattle, Washington 98195, United States.
Journal of the American Chemical Society
|July 31, 2023
概括
将2D范德瓦尔斯铁磁体CrX3与Yb3+合,将宽光发光转化为尖的Yb3+发光. CrI3:Yb3+显示出独特的低能排放和短衰变,由于高协同性.
科学领域:
- 材料科学
- 固态物理
- 光谱学
背景情况:
- 有层的2D范德瓦尔斯铁磁体 (CrX3,X=Cl,Br,I) 呈现宽带的d-d光发光 (PL).
- 像Ytterbium (Yb3+) 这样的光学杂质可以通过发光来改变材料特性.
研究的目的:
- 为了研究用Yb3+合的CrX3 (X=Cl, Br, I) 的结构和光谱特性.
- 了解Yb3+对CrX3材料光发光的影响.
主要方法:
- CrX3:Yb3+化合物的合成和结构特征.
- 扩展的X射线吸收细结构 (EXAFS) 的测量.
- 低温 (4K) 光发光 (PL) 光谱学
- 角度重叠模型 (AOM) 的计算.
主要成果:
- Yb3+ 离子在 CrX3 格子中占据替代八面体位,其 Yb-X 键的长度略大于 Cr-X.
- 在Cr3+d-d和连接物到金属电荷转移 (LMCT) 波段的光刺激有效地使Yb3+f-f发射敏感.
- CrCl3:Yb3+和CrBr3:Yb3+具有典型的Yb3+排放和较长的衰变时间 (0.5-1.0毫秒).
- CrI3:Yb3+ 呈现出异常的低能Yb3+ 发射和较短的衰变时间 (8 μs),这归因于高协同效应.
结论:
- 在CrX3中,Yb3+兴奋剂有效地将宽带d-dPL转化为利的Yb3+f-f发射.
- 在CrI3:Yb3+中,Yb3+的电子结构受到强烈的协同效应的影响,从而产生独特的光谱性质.
- 这些发现突显了Yb3+化CrX3在光电子应用中的潜力.
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