Core–Shell Confined Perovskite Quantum Dots for Enhanced Circularly Polarized Luminescence and Stability

Intrinsically chiral active optical materials are currently a subject of intense research. While chiral ligand modification is an effective strategy for imparting chirality to perovskite quantum dots (PQDs), it faces challenges related to a limited luminescence dissymmetry factor and stability. Herein, this work reports a one-pot synthesis of R-/S-CsPbBr₃@SiO₂ PQDs. The chiral characteristics of R-/S-CsPbBr₃@SiO₂ PQDs originate from the surface anchoring of R-/S-2-phenylglycinol (R-/S-Phe), which triggers chiral lattice distortion of the [PbBr₆]⁴⁻ octahedra and strong electronic coupling. Notably, the silica shell acts not just as a protective barrier but as a spatial confinement matrix that facilitates a higher density of chiral ligand loading, thereby amplifying the dissymmetry factor (glum = -1.14 × 10⁻²) by nearly an order of magnitude compared to bare counterparts. The encapsulated PQDs simultaneously achieve a high photoluminescence quantum yield of 84 ± 1%, exceptional water stability, and intense circularly polarized luminescence. This work offers a strategy for enhancing the chiroptical signals in multifunctional chiral metal halides.