We report a facile method to realize the selective synthesis of Cs_xPb_yBr_z-based perovskites, including CsPbBr₃, Cs₄PbBr₆ and CsPb₂Br₅. The use of an appropriate amount of N,N-dimethylformamide (DMF) solvent is experimentally determined to play a critical role in the controlled formation of various perovskite products. With continuously increasing DMF concentration, first CsPbBr₃ nanocrystals with tunable size can be achieved, and then the production of Cs₄PbBr₆ and CsPb₂Br₅ perovskite analogues is successively realized. Our findings present a novel path for the controlled synthesis of other perovskite analogues for specific applications.

中文翻译：

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Cs _x Pb _y Br _z基钙钛矿可控合成的简便方法

我们报告了一种简便的方法来实现Cs _x Pb _y Br _z基钙钛矿的选择性合成，包括CsPbBr ₃，Cs ₄ PbBr ₆和CsPb ₂ Br ₅。实验确定使用适量的N，N-二甲基甲酰胺（DMF）溶剂在各种钙钛矿产品的受控形成中起关键作用。随着DMF浓度的不断增加，首先可以获得尺寸可调的CsPbBr ₃纳米晶体，然后生产Cs ₄ PbBr ₆和CsPb ₂ Br相继实现了_5个钙钛矿类似物。我们的发现为针对特定应用的其他钙钛矿类似物的受控合成提供了一条新途径。