All-Solid-State Mechanochemical Synthesis and Post-Synthetic Transformation of Inorganic Perovskite-type Halides.

All-inorganic and hybrid perovskite type halides are generally synthesized by solution-based methods, with the help of long chain organic capping ligands, complex organometallic precursors, and high boiling organic solvents. Herein, a room temperature, solvent-free, general, and scalable all-solid-state mechanochemical synthesis is demonstrated for different inorganic perovskite type halides, with versatile structural connectivity in three (3D), two (2D), and zero (0D) dimensions. 3D CsPbBr3 , 2D CsPb2 Br5 , 0D Cs4 PbBr6 , 3D CsPbCl3 , 2D CsPb2 Cl5 , 0D Cs4 PbCl6 , 3D CsPbI3 , and 3D RbPbI3 have all been synthesized by this method. The all-solid-state synthesis is materialized through an inorganic retrosynthetic approach, which directs the decision on the solid-state precursors (e.g., CsX and PbX2 (X=Cl/Br/I) with desired stoichiometric ratios. Moreover, post-synthetic structural transformations from 3D to 2D and 0D perovskite halides were performed by the same mechanochemical synthetic approach at room temperature.