Amplifying the Circularly Polarized Luminescence of CsPbBr 3 Nanocrystals by Chiral Metal–Organic Frameworks: In‐Situ Growth, Chiral Assemble, and Chirality Transfer

Abstract Halide perovskites have risen as promising circularly polarized luminescent (CPL) materials for applications in 3D displays, optical anti‐counterfeiting, and information storage. And yet, achieving highly anisotropic CPL emission from achiral halide perovskites remains fraught with challenges. Herein, the helical channels of chiral MOFs (L/D‐MOFs) are utilized as chiral templates for the in‐situ growth of CsPbBr 3 perovskite nanocrystals (NCs), generating CPL‐active CsPbBr 3 @L/D‐MOFs materials with high luminescence dissymmetry factors (|g lum |, 8.39×10 −3 ) and high photoluminescence quantum yields (QY, 78%). Synchrotron‐radiation‐based X‐ray absorption spectroscopy clearly verifies that the embedded CsPbBr 3 NCs inherit the helicity of L/D‐MOFs through strong Cd─Br coordination bonds, thereby facilitating chirality transfer from L/D‐MOFs to CsPbBr 3 NCs. Additionally, the efficient Förster resonance energy transfer (FRET) from chiral L/D‐MOFs to CsPbBr 3 NCs further amplifies the CPL signal of CsPbBr 3 NCs. Benefiting from the excellent CPL properties and tunable emission, the CsPbX 3 @L/D‐MOFs demonstrate great potential in CPL‐LEDs. This work proposes a viable strategy for the rational design of high‐performance CPL‐active perovskite materials and offers profound insights into the chirality transfer mechanism.