MOF‐on‐MOF Core–Shell Heterostructure With Synergistic Porous Interface for Highly Efficient Propane/Propylene Separation

ABSTRACT Propylene is one of the most important industrial chemicals, while energy‐efficient separation of propylene from the propane/propylene mixtures remains challenging. Conventional metal‐organic frameworks (MOFs) with tunable pore structures enable selective adsorption, yet they typically suffer from an intrinsic trade‐off between uptake capacity and selectivity. This work reports a Ni‐MOF‐74@ZU‐609 MOF‐on‐MOF core–shell heterostructure that exhibits both high adsorption capacity and selectivity, arising from the synergistic interface between the integrated Ni‐MOF‐74 adsorptive core and the ZU‐609 separation shell. Dynamic breakthrough experiments show that the interface‐optimized Ni‐MOF‐74@ZU‐609 core–shell heterostructure exhibits ultrahigh dynamic selectivity (5.51) and high dynamic capacity (1.14 mmol g −1 ) for C 3 H 6 at 298 K and 1 bar, outperforming either of the pristine MOFs, which further confirms the efficacy of the interfacial effect. This study demonstrates that precise interfacial engineering in MOF heterostructures successfully overcomes the long‐suffered capacity‐selectivity trade‐off, thereby establishing a versatile design platform for high‐performance gas separation materials.