具有电荷转移状态特征的2D矿单晶的双排放波段
Bogdan Dryzhakov1,2, Benjamin J Lawrie3,4, Jakob Zosa Celio1
1Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States.
ACS nano
|June 27, 2023
概括
这项研究揭示了PEA2PbI4矿中引入的间隙状态如何使绿色和红色光辐射之间的切换成为可能. 这些状态创建双电子框架,允许选择性紫外线和红外线光访问可调节的光发光.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 光电学是指光电子产品.
背景情况:
- 混合化二维矿表现出宽带发射,这是科学文献中争论的现象.
- 了解这种排放的来源对于开发先进的光电子设备至关重要.
研究的目的:
- 为了研究带隙状态的PEA2PbI4矿中带隙状态下的和带隙以上的发射和吸收.
- 为了阐明光发光 (PL) 从窄带绿色转换为宽带红色发射背后的机制.
主要方法:
- PEA2PbI4的单晶生长与受控的间隙状态.
- 电子能量依赖的阴极发光光谱学.
- 激发 - 排放功率斜率分析.
- 上转换的短暂吸收 (TA) 光谱.
- 探头暂时吸收光谱学.
- 极化和磁场效应测量.
主要成果:
- 差距状态创建共存的内在和异构的电子框架,分别通过紫外线和红外线可访问.
- 宽带红色PL源自大量的异构结构框架,通过阴极光发光深度分析得到证实.
- 红色PL (655nm) 的IR上转激发是异构结构框架内的多光子过程,表明非线性光学响应.
- 暂时的吸收显示了从上转换的间隙状态的快速放松 (<4 ps).
结论:
- 该研究阐明了二维矿的双重排放机制,将其与不同的电子框架和间隙状态联系起来.
- 这些发现证实了异构结构框架与电荷转移状态的结晶学对齐,由极化红色PL和磁场效应证明.
- 这项工作提供了对控制矿光辐射的洞察力,用于可调节光电子产品的潜在应用.
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