Efficient Circularly Polarized Luminescence from Mn‐Br Hybrid Perovskite Assembled by Achiral Architectures

Circularly polarized luminescence (CPL)‐active materials have attracted considerable attention due to their potential applications in various advanced technological fields. CPL activity typically requires compounds that crystallize in noncentrosymmetric chiral space groups. Achieving noncentrosymmetric crystal structures using achiral molecular architectures is highly appealing but remains a significant challenge. Herein, we present a strategy for designing and synthesizing high‐performance CPL materials via crystallization‐driven self‐assembly using achiral architectures. We successfully obtained Mn2+‐based halide enantiomeric hybrids (P‐1 and M‐1), self‐assembled from [MnBr4]2‐ anions and rotational symmetric [Pr‐dabco]2+ cations (Pr‐dabco2+ = 1‐Propyl‐1,4‐diazabicyclo‐[2.2.2]octan‐1‐ium), crystallizing in the chiral space group P212121. The single crystals of 1 exhibit exceptionally high CPL performance, with a luminescence dissymmetry factor |glum| and photoluminescence quantum yield (PLQY) up to 4.8×10‐2 and 86.8%, respectively, thus a record‐high figure of merit (FM) of 4.2×10‐2 among reported Mn2+‐based CPL materials. Furthermore, P/M‐1 based UV‐LED devices demonstrated outstanding light‐emitting performance, including high color‐purity, excellent stability, remarkable luminous brightness (74,591.94 cd m‐2), and a high electroluminescence dissymmetry factor (glum) value of 3.6×10‐2. This study offers a robust strategy for the design and development of high‐performance CPL materials utilizing achiral molecular architectures.