Domain-Confined Perovskite in Lanthanide MOFs for Multiresponse CPL Switches and Information Encryption

Circularly polarized luminescence (CPL) switches have received considerable attention for their potential applications in next-generation information technologies. Nevertheless, the development of solid-state multiresponse CPL switches remains a challenge. Herein, the chiral coassembled material MAPbX₃@L/d-Phe-LnMOF was synthesized by self-assembly using lanthanide metal-organic frameworks (MOFs) as the host and perovskite quantum dots (QDs) as the guest, using the host-guest space-confined strategy (Ln = Eu³⁺, Tb³⁺, MA = CH₃NH₃⁺, X = Cl^-, Br^-, I^-, l-Phe = l-phenylalanine). The nonchiral MAPbX₃ inherits the chirality of the MOFs through the host-guest ligand bond (Pb-O and Eu-Br). MAPbX₃@L/d-Phe-LnMOF exhibits long-term photoluminescence quantum yield (PLQY ∼ 11%) and enhanced fluorescence lifetime, good thermal stability of CPL in air, and photoswitching properties under different UV irradiation. Based on the two chiral emission centers and their different properties, reversible switching of CPL was realized under chemical substances (H₂O/MABr solution). This study provides a new method for the preparation of solid-state CPL composites and expands new applications for CPL-based optical switches.