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 (P_s) 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.