A Zn(ii) pillared-layer ultramicroporous metal-organic framework with matching molecular pockets for C₂H₂/CO₂ separation

Similar sizes and boiling points of acetylene (C₂H₂) and carbon dioxide (CO₂) make CO₂ separation from C₂H₂/CO₂ mixtures challenging. In this work, a pillared-layer ultramicroporous Zn-mipa-datz material featuring a C₂H₂-matching cavity was successfully prepared to achieve high-efficiency C₂H₂/CO₂ separation. The separation performance of Zn-mipa-datz on C₂H₂/CO₂ mixtures was investigated through gas adsorption isotherms and dynamic breakthrough experiments. Zn-mipa-datz possessed high C₂H₂ separation efficiency for C₂H₂/CO₂ mixtures. The molecular simulation demonstrated that the strong C₂H₂-host interaction was achieved by the synergistic effect of C-N electrostatic interactions and C-H⋯N H bonds.