Supramolecularly engineered ZIF-L/GO/Pebax mixed-matrix membranes with intercalated network structures for enhanced CO2/N2 separation

Membrane separation has emerged as a competitive energy-efficient approach for carbon capture and flue gas treatment. Membrane materials and structures are the core of gas separation membranes, which collectively govern gas molecular mass transfer and separation behaviors. Two-dimensional (2D) graphene oxide (GO) porous nanosheets hold great promise for gas separation due to their nanoscale thickness and structural tunability, but they are often limited by low permeability. Herein, we propose a supramolecular strategy to fabricate ZIF-L/GO/Pebax mixed matrix membranes with intercalated network architectures for efficient CO 2 /N 2 separation. Leaf-like ZIF-L expands the interlayer spacing of GO nanosheets and constructs high-speed continuous gas transport pathways within the membrane. This unique intercalated structure provides abundant CO 2 -philic sites, significantly enhancing CO 2 solubility and enabling highly selective gas molecular sieving. Moreover, hydrogen bonds and chelation coordination interactions between ZIF-L/GO and polymer matrix ensure excellent interfacial compatibility while reinforcing structural stability. This supramolecular structural engineering approach effectively mitigates the limitations of traditional membranes, achieving CO 2 permeability of 1000.8 Barrer and CO 2 /N 2 selectivity of 45, exceeding the 2008 Robeson upper bound and approaching the 2019 limit. Additionally, the membrane displays superior mechanical properties and long-term operational stability, providing a promising avenue toward high-performance materials for efficient CO 2 capture.