Dimensional control of chiral perovskites for high-performance circularly polarized light detection via ligand engineering

• Synthesis of novel chiral ligands with controlled substitution positions. • Intramolecular interactions impact the nano structures of chiral perovskites . • Variations in dimensionality and chiroptical properties of chiral perovskites . • Enhanced chiroptical properties via transformation from 2D to 1D chiral perovskites. • Optimum circularly polarized light discrimination up to anisotropy factor of 1.25. Chiral hybrid organic–inorganic perovskites (HOIPs), embedded with chiral organic cations, have emerged as promising materials for optoelectronic devices due to their unique circularly polarized light (CPL) discrimination properties. However, the function of chiral organic ligands, which are the origin of chirality and simultaneously the structural building block in HOIPs, has not been thoroughly explored beyond commercially available amines. Here, we synthesized three phenyl-based chiral organic cations with different substitution positions ( ortho , meta and para ) of chlorine atom, which influenced hydrogen bonding geometries within the HOIP’s inorganic framework. Notably, controlling molecular interactions resulted in a change in dimensionality and an enhancement in the chiroptical properties of perovskite crystals, exhibiting the exceptional anisotropy factors of up to 1.25 in a self-powered real-time sensing mode. These results give insights into the control of structure–property relationship via ligand molecular engineering and demonstrate high potential of chiral HOIPs for use in real-time CPL detectors.