Metal halide perovskites (MHPs) are promising materials for a range of optoelectronic applications owing to their unique structures and optical properties. The photoluminescence (PL) property of MHPs is crucial for their applications. All‐inorganic MHPs such as CsPbBr₃, CsPb₂Br₅ and Cs₄PbBr₆, have been widely investigated due to their high PL quantum yield (QY). However, the PL mechanisms of these perovskites still remain controversial and lack a unifying explanation. In this review, we have summarized the recent efforts to reveal the emission process of all‐inorganic cesium lead bromide perovskites nanocrystals (NCs) by utilizing single particle spectroscopy. The recent research advances on the understanding of exciton nature in CsPbBr₃ and PL emission originating from intrinsic point defects or impurity CsPbBr₃ phase in CsPb₂Br₅ and Cs₄PbBr₆ are summarized. Understanding the relationship between the structure and associated PL property of MHPs paves the way for their potential applications.

中文翻译：

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单粒子光谱揭示全无机溴化铯铅钙钛矿的光致发光机理

金属卤化物钙钛矿（MHP）由于其独特的结构和光学特性，是用于各种光电应用的有前途的材料。MHP的光致发光（PL）特性对其应用至关重要。全无机MHP，例如CsPbBr ₃，CsPb ₂ Br ₅和Cs ₄ PbBr ₆由于其高PL量子产率（QY），已被广泛研究。然而，这些钙钛矿的PL机理仍然存在争议，并且缺乏统一的解释。在这篇综述中，我们总结了最近通过利用单粒子光谱法揭示全无机溴化铯铯铅钙钛矿纳米晶体（NCs）的发射过程的努力。CsPbBr ₃和CsPb ₂ Br ₅和Cs ₄ PbBr _6的本征点缺陷或杂质CsPbBr ₃相引起的PL发射的最新研究取得了进展。总结。理解MHP的结构与相关PL特性之间的关系为它们的潜在应用铺平了道路。