Supramolecular Rotor Assembly for the Design of a Hybrid Ferroelectric‐Antiferromagnetic Multiferroic Semiconductor

Ferroelectric (FE)‐antiferromagnetic (AFM) multiferroic materials have sparked growing interest due to their huge possibilities in energy‐saving, photoelectric devices, nonvolatile storage, and switches. However, realizing FE‐AFM properties in a hybrid molecular material is difficult because ferroelectric and magnetic orders are commonly mutually exclusive. Here, we report an FE‐AFM multiferroic semiconductor [NH4(18‐crown‐6)]2[Mn(SCN)4] (NCMS) by supramolecular assembly approach via molecular rotor synthon [NH4(18‐crown‐6)] and inorganic magnetic module [Mn(SCN)4]. Interestingly, NCMS shows good ferroelectricity with a spontaneous polarization (Ps) of 5.94 μC cm−2 higher than most crown‐ether‐based ferroelectrics. Especially, the realization of antiferromagnetism is for the first time in the crown ether hybrid perovskite ferroic systems. Additionally, semiconductor NCMS displays an X‐ray radiation detection response with a large photo/dark current on‐off ratio (197). Our study not only gives a deep insight into understanding multiferroic properties but also provides a novel and efficient approach to realizing high‐performance hybrid multiferroic materials.