Phonon Involved Photoluminescence of Mn 2+ Ions Doped CsPbCl 3 Micro‐Size Perovskite Assembled Crystals

Abstract Mn 2+ ions doped CsPbCl 3 perovskite nanocrystals (NCs) exhibit superiority of spin‐associated optical and electrical properties. However, precisely controlling the doping concentration, doping location, and the mono‐distribution of Mn 2+ ions in the large‐micro‐size CsPbCl 3 perovskite host is a formidable challenge. Here, the micro size CsPbCl 3 perovskite crystals (MCs) are reported with uniform Mn 2+ ions doping by self‐assembly of Mn 2+ ions doped CsPbCl 3 perovskite NCs. The electron–phonon coupling strength is enhanced in the perovskite self‐assembled CsPbCl 3 MCs, which remarkably accelerates the PL decay of Mn 2+ ions in room temperature. Furthermore, the phonon‐involved PL emission splits to two peaks at low temperature of 80 K, due to the phonon emission and absorption‐induced energy exchange for exciton recombination in Mn 2+ ions. These findings not only demonstrate a novel material system but also introduce a new theoretical framework for phonon‐modulated PL manipulation in Mn 2+ ‐doped perovskite materials.