Unraveling the mechanochemical synthesis and luminescence in Mn ^II -based two-dimensional hybrid perovskite (C ₄ H ₉ NH ₃ ) ₂ PbCl ₄

The mechanochemical route is a facile and fast way and has received much attention for developing versatile advanced functional materials. Herein, we reported a mechanochemical synthesis for incorporating divalent manganese ions (Mn ^II ) into a two-dimensional (2D) hybrid perovskite (C ₄ H ₉ NH ₃ ) ₂ PbCl ₄ . The mild external stimuli originating from the grinding at room temperature enabled the formation of MnII-doped 2D hybrid perovskites, and rapidly changed the luminescence characteristics. The photoluminescence analyses show that the violet and orange emissions are attributed to (C ₄ H ₉ NH ₃ ) ₂ Pb _1–x Mn _x Cl ₄ band-edge emission and the T ₁ → ⁶ A ₁ transition of Mn ²⁺ resulting from an efficient energy transfer process, respectively. Site preference and distribution of the doped Mn ²⁺ cations on the locations of Pb ²⁺ were analyzed. The formation energy calculated by the density functional theory (DFT) indicates that the Mn ²⁺ ions can rapidly enter the crystal lattice due to the unique 2D crystal structure of the hybrid perovskite. Such a case of mechanochemical synthesis for the 2D hybrid perovskite motivates many novel emerging materials and the related applications.