Chiral 3D Perovskite Formation Induced by Chiral Templates

Chiral 3D perovskites pose challenges compared to lower-dimensional variants due to limited chiral organic cation options. Here, we present a universal and controlled method for synthesizing chiral 3D lead halide perovskites using organic amines or alcohols as chiral templates. Introducing these templates to PbCl₂ in N,N-dimethylformamide (DMF) under acidic conditions induces the crystallization of R/S [DMA]PbCl₃ (DMA = dimethylamine). The resulting structure aligns with the templates used, stemming from the helical Pb₂Cl₉^5- chain as verified by single-crystal X-ray diffraction. Furthermore, the chiral perovskite exhibits absorption and circular dichroism (CD) signals in the high-energy band, enabling the circularly polarized light (CPL) detection in the UV spectrum. A CPL detector constructed by this chiral perovskite demonstrates excellent performance, boasting an anisotropy factor for photocurrent (g_Iph) of 0.296. Our work not only introduces a novel and controllable method for crafting chiral perovskites but also opens new avenues for circularly polarized light detection.