ABSTRACT As an indispensable part of inorganic lead halide perovskite (LHP) nanocrystals (NCs), red-emitting cesium lead iodide (CsPbI3) NCs with suitable band gap have attracted more and more attention in recent years. Researches have showed that bulk CsPbI3 with cubic phase cannot maintain its structure and will transform into the orthorhombic phase or even non-perovskite structure without the high-temperature condition. Interestingly, cubic phase CsPbI3 (α-CsPbI3) in nanoscales with some special modifications were found to stabilize the cubic phase possibly even under room temperature. However, its poor stability has been a nightmare in a long time and limits the optical properties and its application severely. Upholding the idea of solving these problems, many efforts have been devoted to improving its stability and optical performance. In this review, the factors of instability from different sides are described briefly at the beginning, then we summarize some works which are committed to ameliorating the poor stability of CsPbI3 NCs and divide them into several parts. In the end, some unresolved challenges and possible research opportunities are proposed.

中文翻译：

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提高碘化铯铅钙钛矿纳米晶体的稳定性：最新进展、挑战和机遇

摘要 作为无机卤化铅钙钛矿（LHP）纳米晶体（NCs）的重要组成部分，具有合适带隙的红色铯碘化铅（CsPbI3）NCs近年来受到越来越多的关注。研究表明，立方相的块状CsPbI3不能保持其结构，在没有高温条件的情况下会转变为正交相甚至非钙钛矿结构。有趣的是，发现具有一些特殊修饰的纳米级立方相 CsPbI3（α-CsPbI3）即使在室温下也可能稳定立方相。然而，其稳定性差长期以来一直是一个噩梦，严重限制了其光学性能及其应用。秉持解决这些问题的思路，一直致力于提高其稳定性和光学性能。在这篇综述中，首先简要描述了不同方面的不稳定因素，然后我们总结了一些致力于改善 CsPbI3 NCs 稳定性差的工作，并将它们分为几个部分。最后，提出了一些尚未解决的挑战和可能的研究机会。