Hydrogen-Bond Reinforced Chiral Indium-Based Hybrid Metal Halides for Circularly Polarized Luminescence

Circularly polarized luminescence (CPL) materials are highly attractive for next-generation photonic and information technologies, yet achieving both a large luminescence dissymmetry factor (g lum ) and near-unity photoluminescence quantum yield (PLQY) remains challenging in lead-free chiral metal halides. Here, we report a pair of zero-dimensional chiral indium-based chloride enantiomers, (R/S-AQ) 2 In 1– x Sb x Cl 7 (AQ = 3-aminoquinuclidine), enabled by Sb 3+ -doping. A dense interfacial N–H···Cl hydrogen-bond network strengthens organic–inorganic coupling and is likely to facilitate chiral transfer, while Sb 3+ incorporation activates highly efficient broadband self-trapped exciton emission. As a result, the enantiomers exhibit near-unity PLQY (up to 99.32%) together with mirror-image CPL signals with |g lum | ≈ 2.0 × 10 –2 . A CP-LED based on a commercial 280 nm UV chip shows stable device emission under electrical driving while retaining circular polarization. Our work demonstrates an effective strategy for co-optimizing efficiency and polarization in chiral metal halides toward practical CPL devices.