Chiral Zero-Dimensional Transition Metal Halide Hybrid Perovskite with Ehanced Circular Dichroism and Magnetism

Noncentrosymmetric chiral organic–inorganic hybrid perovskite materials exhibit significant potential for applications in spintronics and other optoelectronic devices. While lead halide hybrid perovskite materials have demonstrated outstanding optoelectronic and spin-charge transport properties, the exploration of nontoxic and lead-free alternatives remains highly necessary. Here, we synthesize a range of chiral hybrid halides (R/S-MBA)2MX4 (MBA = methylbenzylammonium; M = Co, Mn, and Zn, X = Cl and Br) with distinctive 0D MX4 tetrahedral structural motifs. Various optical bands exhibit significant chiroptical activity and magnetism in this series of materials. During the thin film preparation process, (MBA)2ZnBr4 undergoes a phase transition from an orthorhombic structure to a monoclinic structure after being spin-coated and annealing. On the other hand, (MBA)2ZnCl4 maintains its monoclinic structure throughout the process. The study contributes to the advancement of spintronics based on transition-metal hybrid systems by extending the exploration of stable and environmentally friendly metal–organic halides.