Achiral Cation-Induced Chirality Tuning in Cycloalkyl Chiral Cation-Based Quasi-1D and 2D Perovskites

Hybrid organic–inorganic perovskites have garnered significant attention in optoelectronics due to their exceptional optical and electrical properties. Among them, low-dimensional chiral perovskites represent a promising class of optoelectronic materials. However, most existing studies focus on chiral organic cations with aromatic structures. In this work, we utilize the cycloalkyl chiral cation (R)-(−)-1-cyclohexylethylammonium (R-CHEA⁺) as a chiral spacer and incorporate achiral alkyl and aryl cations to systematically investigate the impact of molecular rigidity on structural and chiroptical properties of chiral lead iodide perovskites. Structural characterization reveals that the structural rigidity of chiral cations is crucial for efficient chirality transfer across the organic–inorganic interface and for the structural transition from quasi-1D to 2D perovskites. Our findings suggest a strategy to enhance rigidity in chiral cations, improving chirality transfer efficiency. This study provides insights into the mechanism of chirality transfer in chiral perovskites, offering a promising path for future advancements in chiroptoelectronics.