Research on the Effects of Strain Control on the Energy Bands of Metal Halide Perovskites

金属卤化物钙钛矿(MHPs)是一类具有优异光电性能的新型半导体材料，在光电器件方面取得了显著的成功。但由于钙钛矿本征结构不稳定，有机组分挥发性强，易发生离子迁移与相分离，缺陷态诱导降解等性质限制了其实际应用。近年来，应变工程被发现可有效改善钙钛矿材料的光电性质和器件性能，为钙钛矿材料器件性能的优化提供了新的研究视角，本文综述了应变的来源、表征技术、应变对卤化物钙钛矿能带的影响以及控制应变的各种策略。我们相信，这一综述将进一步促进研究人员对应变效应的更深入理解，并加强对应变工程的研究活动，以进一步提高性能，特别是器件的稳定性，从而实现商业化。Metal halide perovskites (MHPs) are a new class of semiconductor materials with excellent optoelectronic properties and have achieved remarkable success in optoelectronic devices. However, the practical application of perovskites is limited due to the instability of their intrinsic structure, the strong volatility of organic components, the propensity for ion migration and phase separation, and degradation induced by defect states. In recent years, it has been found that strain engineering can effectively improve the optoelectronic properties and device performance of perovskite materials, providing a new research perspective for the optimization of perovskite device performance. This review summarizes the sources of strain, characterization techniques, the impact of strain on the energy bands of halide perovskites, and various strategies to control strain. We believe that this review will further promote researchers’ deeper understanding of strain effects and strengthen their research activities in strain engineering to improve performance, particularly the stability of devices, for commercialization.