光生成的I2如何诱导混合化 Perowskites中的I-丰富相位形成
Yang Zhou1, Simone C W van Laar2, Daniele Meggiolaro3
1Center for Nano Science and Technology@Polimi, Istituto Italiano di Tecnologia, via Rubattino 81, Milano, 20134, Italy.
Advanced materials (Deerfield Beach, Fla.)
|September 18, 2023
概括
照明导致混合化 Perowskites (LMHPs) 的丰富相形成,通过产生I2. 这破坏了带隙的稳定性,但了解缺陷密度和化物结合强度为稳定的光电子设备提供了设计规则.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 光电学是指光电子产品.
背景情况:
- 混合化 Perowskites (LMHPs) 提供可调节的带隙,对于光电子设备至关重要.
- 照明诱导的丰富酸相的形成使LMHP中的带隙不稳定,阻碍了它们的应用.
- 了解这一阶段不稳定的背后机制对于LMHP发展至关重要.
研究的目的:
- 阐明照明在LMHP中促进丰富相位形成的机制.
- 确定控制LMHP中带隙不稳定的关键因素.
- 建立用于光电子应用的稳定LMHP的设计原则.
主要方法:
- 研究了光生成 (I2) 在相位转换中的作用.
- 分析了涉及I2和化物离子 (Br-) 形成三化物离子的反应途径.
- 与原生缺陷密度和化物结合强度相关的相位稳定性.
主要成果:
- 光生成的I2,由电荷载体被困在间隙处,驱动形成富含的相.
- I2 与 Br- 的反应形成 I2Br- ,其中化离子进一步与格子 Br-.交换.
- 该过程的有效性取决于矿的晶体结构稳定性,特别是缺陷密度和Br-结合强度.
结论:
- 在LMHP中,带隙不稳定性是由I2生产 (与缺陷密度相关) 和Br-结合强度决定的.
- 这项研究提供了对LMHP降解途径的基本见解.
- 提供化学成分的设计规则,以提高光电子设备的LMHP稳定性和性能.
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