We report on in situ observations of nucleation, growth, and aggregation of hybrid organic–inorganic perovskites by liquid-cell transmission electron microscopy. Direct crystallization of hybrid CH₃NH₃PbI₃ nanoparticles is achieved through an electron beam-assisted solvent evaporation approach. Time-lapse liquid-cell TEM imaging of the nanoparticles reveals a growth trend which is not entirely consistent with the classical Lifshitz–Slyozov–Wagner growth model. Significantly complex dynamical behaviors are observed during the coalescence process of CH₃NH₃PbI₃ nanoparticles. We propose that the chemical instability inherent in the hybrid perovskite iodides should be considered to understand this phenomenon in addition to the oriented attachment mechanism. This study provides a useful reference for understanding the intriguing chemical and physical properties of hybrid organic–inorganic perovskites.

中文翻译：

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液体细胞透射电镜观察杂化钙钛矿纳米粒子的异常生长和聚结动力学

我们报告了通过液体细胞透射电子显微镜观察到的混合有机-无机钙钛矿的成核，生长和聚集的原位观察结果。杂化CH ₃ NH ₃ PbI ₃纳米粒子的直接结晶是通过电子束辅助溶剂蒸发方法实现的。纳米粒子的时移液体细胞TEM成像显示出增长趋势，这与经典的Lifshitz-Slyozov-Wagner生长模型并不完全一致。在CH ₃ NH ₃ PbI ₃的聚结过程中观察到非常复杂的动力学行为纳米粒子。我们建议，除了定向附着机制外，还应考虑杂化钙钛矿碘化物固有的化学不稳定性，以了解这种现象。该研究为理解有机-无机杂化钙钛矿的有趣的化学和物理性质提供了有用的参考。