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

Abstract

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.