Formation of iminium ions during the processing of metal halide perovskites

Abstract

Ammonium ions are a key component of many organic–inorganic metal halide materials. We show that the hexagonal perovskite (Me₂NH₂)PbI₃ is rapidly transformed to iminium-based perovskites (Me₂CNMeR)PbI₃ (R = Me, Et), simply by stirring the material in the respective ketone at room temperature, triggering clear changes in the materials’ photophysical properties.