Homochiral metal–organic framework membranes synthesized using a nonstochastic chiral bias for enhanced enantioselective separation

Abstract

The synthesis of enantiopure homochiral metal–organic frameworks (MOFs) based on achiral materials is highly appealing. Due to their chiral properties and separation capabilities, homochiral MOF membranes have garnered significant attention. Nonetheless, fabricating high-quality homochiral MOF membranes synthesized from achiral materials remains a formidable challenge. In this study, chiral (P)-CoMOF membranes were fabricated through spontaneous mirror symmetry breaking, utilizing an achiral ligand, dimethyl pyridine-2,5-dicarboxylate, as a linker. The membrane exhibits exceptionally high and stable enantioselectivity. At feed solution concentrations of 0.05 and 0.01 mol L⁻¹, the enantioselectivity of S-(+)-ibuprofen over R-(−)-ibuprofen reached 100%. This study demonstrates that chiral MOF membranes can be more readily synthesized from achiral raw materials through the spontaneous mirror-symmetry breaking crystallization mechanism. This approach is both more convenient and cost-effective compared to synthesis methods that utilize chiral ligands or chiral inducers. The findings highlight the potential of fabricating pure chiral MOF membranes from achiral materials for applications in chiral separations.