揭示了Cs2AgBiBr6 (纳米) 晶体中的宿主-Yb3+能量转移:Yb3+ (纳米) 晶体中的能量转移
Jur W de Wit1, Lars L Sonneveld1, Andries Meijerink1
1Debye Institute for Nanomaterials Science, Utrecht University, Utrecht 3584 CC, The Netherlands.
Chemistry of materials : a publication of the American Chemical Society
|April 1, 2024
概括
这项研究调查了Ytterbium (Yb3+) 在无Cs2AgBiBr6双矿中使用的兴奋剂. 研究人员发现,Yb3+通过独特的电荷捕获机制使近红外辐射成为可能,而不是宿主能量传输.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 固态物理 固态物理
背景情况:
- Cs2AgBiBr6双矿是一种无替代品,可以与可调节的光学特性进行合物矿.
- 用兰坦化离子进行兴奋剂,例如Ytterbium (Yb3+),提供了一种修改排放颜色的途径.
- 之前,Cs2中的Yb3+排放的能量转移机制尚不清楚.
研究的目的:
- 阐明Cs2AgBiBr6纳米和微晶体中的Yb3+的发光和敏感化机制.
- 要了解Yb3+结合如何影响Cs2AgBiBr6主机的光学特性.
- 为了确定近红外 (NIR) 辐射的途径,在Yb3+-doped Cs2AgBiBr6.
主要方法:
- 合成Yb3+-化Cs2AgBiBr6的纳米和微晶体.
- 摄影发光光谱学 (温度依赖和时间分辨率) 在未使用和Yb-doped样本上.
- 分析排放光谱以确定宿主和辅助剂的贡献.
主要成果:
- Yb3+ 兴奋剂引入了特征性的~1000nm NIR线辐射,而不会显著改变宿主的红色辐射.
- 能量转移到Yb3+并不会通过Cs2AgBiBr6宿主的红色发射状态发生.
- 观察到一种与红色发射状态相比的放松过程与Yb3+上的电荷载体捕获.
结论:
- 在光激发的电荷载体被困在Yb3+上后,NIR发射源于Yb3+ 4f-4f过渡.
- 这种捕获形成了一个电荷转移状态,与Yb3+兴奋状态相放松,导致NIR发射.
- 这些发现澄清了敏感化机制,为使用无矿的新型光电子应用铺平了道路.
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