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Updated: Aug 3, 2025

Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
Thermally driven phase transition of halide perovskites revealed by big data-powered in situ electron microscopy
Xin Luo1, Weiyan Liu1, Zeyu Wang1
1School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China.
Abstract:
Halide perovskites are promising light-absorbing materials for high-efficiency solar cells, while the crystalline phase of halide perovskites may influence the device's efficiency and stability. In this work, we investigated the thermally driven phase transition of perovskite (CsPbIxBr3-x), which was confirmed by electron diffraction and high-resolution transmission electron microscopy results. CsPbIxBr3-x transitioned from δ phase to α phase when heated, and the γ phase was obtained when the sample was cooled down. The γ phase was stable as long as it was isolated from humidity and air. A template matching-based data analysis method enabled visualization of the thermally driven phase evolution of perovskite during heating. We also proposed a possible atomic movement in the process of phase transition based on our in situ heating experimental data. The results presented here may improve our understanding of the thermally driven phase transition of perovskite as well as provide a protocol for big-data analysis of in situ experiments.
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