Universal Strategy of 3D and 2D Hybrid Perovskites Single Crystal Growth via In Situ Solvent Conversion

A novel strategy of hybrid halide perovskite single crystal growth based on a new type of “fugitive” solvent system is proposed. To demonstrate the universality of the developed approach, we have grown a set of high-quality single crystals of 3D hybrid perovskites APbX3 (A = MA+, FA+; X = Br–, I–) with pure and mixed compositions, layered 2D perovskites (BA)2(A)n – 1PbnI3n + 1 (n = 1–4), and iodobismuthates A3Bi2I9. The crystallization was governed by gradual chemical conversion of the initial mixed solvent to a nonsolvent and thus gave yields up to 90%. The growth proceeded within a few hours at moderate temperatures and required no heating/cooling or low-pressure evaporation steps, antisolvents, or any toxic solvents, which makes the whole process uniquely facile and eco-friendly. The high quality of the grown single crystals was confirmed by absorption and photoluminescence spectroscopy, revealing unexpectedly high charge carrier lifetime for 2D perovskites.