Facile Method for the Controllable Synthesis of Cs x Pb y Br z -Based Perovskites

We report a facile method to realize the selective synthesis of Cs x Pb y Br z -based perovskites, including CsPbBr 3, Cs 4 PbBr 6 and CsPb 2 Br 5 . 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 CsPbBr 3 nanocrystals with tunable size can be achieved, and then the production of Cs 4 PbBr 6 and CsPb 2 Br 5 perovskite analogues is successively realized. Our findings present a novel path for the controlled synthesis of other perovskite analogues for specific applications.