Kinetics and energetics of metal halide perovskite conversion reactions at the nanoscale
Kinetics and energetics of metal halide perovskite conversion reactions at the nanoscale
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DOI：
10.1038/s43246-022-00239-1
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发表时间：
2022-04-20
影响因子：
7.8
通讯作者：
Dar, M. Ibrahim
中科院分区：
文献类型：
--
作者：
Arora, Neha;Greco, Alessandro;Dar, M. Ibrahim
金属卤化物到钙钛矿相转化是合成用于光电应用的高质量钙钛矿半导体的简便方法。在这里，这些反应在纳米尺度下通过原位X射线散射进行了研究，揭示了反应动力学，结构和组成之间的联系。理解金属卤化物钙钛矿形成的动力学和能量学，特别是从纳米尺度的结构角度来看，对于钙钛矿器件的发展非常重要。特别是，需要了解钙钛矿转化反应发生的机制及其动力学。在这里，我们研究的结构演变的前体和钙钛矿相使用原位同步辐射X射线散射。这种方法减轻了与照明和基于电子束的技术相关的问题，并允许得出关于这些反应的动力学的结论。我们发现，动力学和晶粒取向强烈依赖于卤化铅框架和A-阳离子的性质，MAPbI（3）的动力学最快，其次是FAPbI（3），MAPbBr（3）最慢。分子动力学模拟和密度泛函理论计算进一步揭示了这些反应是扩散控制的，跳跃时间为5-400 s，证实了实验结果。
Metal halide to perovskite phase conversion is a facile approach for synthesizing high-quality perovskite semiconductors for optoelectronic applications. Here, these reactions are investigated at the nanoscale via in-situ x-ray scattering, revealing links between reaction kinetics, structure and composition.Understanding the kinetics and energetics of metal halide perovskite formation, particularly from the structural point of view at the nanoscale, is important for the advancement of perovskite devices. In particular, insight is needed regarding the mechanisms by which perovskite conversion reactions occur, and their kinetics. Here, we examine the structural evolution of precursor and perovskite phases using in situ synchrotron x-ray scattering. This approach mitigates issues associated with illumination and electron beam-based techniques and allows conclusions to be drawn regarding the kinetics of these reactions. We find that kinetics and grain orientation strongly depend on both the lead halide framework and the nature of the A-cation, with fastest kinetics for MAPbI(3), followed by FAPbI(3), and slowest for MAPbBr(3). Molecular dynamics simulations and density functional theory calculations further reveal that these reactions are diffusion-controlled with a hopping time of 5-400 s, corroborating experimental findings.