Unprecedented Chiral Three‐dimensional Hybrid Organic‐Inorganic Perovskitoids

Abstract Chiral three‐dimensional hybrid organic–inorganic perovskites (3D HOIPs) would show unique chiroptoelectronic performance due to the combination of chirality and 3D structure. However, the synthesis of 3D chiral HOIPs remains a significant challenge. Herein, we constructed a pair of unprecedented 3D chiral halide perovskitoids ( R / S ‐BPEA)EA 6 Pb 4 Cl 15 ( 1‐R/S ) ( R / S ‐BPEA=(R/S)‐1‐4‐Bromophenylethylammonium, EA=ethylammonium), in which the large chiral cations can be contained in the big “hollow” inorganic frameworks induced by mixing cations. Notably, 3D 1‐R/S shows natural chiroptical activity, as evidenced by its significant mirror circular dichroism spectra and the ability to distinguish circularly polarized light. Moreover, based on the unique 3D structure, 1‐S presents sensitive X‐ray detection performance with a low detection limit of 398 nGy air s −1 , which is 14 times lower than the regular medical diagnosis of 5.5 μGy air s −1 . In this work, 3D chiral halide perovskitoids provide a new route to develop chiral material in spintronics and optoelectronics.