Turing Patterned ZIF‐8 Membranes with Engineered Transport Pathways for Gas Separation

Abstract Crystalline porous membranes provide a promising platform for efficient gas separation, as they can overcome the permeability–selectivity trade‐off that limits traditional polymeric membranes. However, challenges remain in simultaneously achieving high separation efficiency and straightforward synthesis. Here, a continuous, flow‐based synthesis of ZIF‐8 membranes featuring dense and tunable Turing patterns is reported. This membrane morphology arises because the inhibitor, 2‐methylimidazole, diffuses much faster than the activator, Zn 2+ , under forced convection. By controlling reactant concentrations and flow rates, the wrinkle amplitude (0.15–1.81 µm) and spacing (1.04–5.39 µm) of the Turing patterns can be precisely adjusted. These engineered membrane features open transport pathways (≈0.4 nm), resulting in a CO 2 permeance of 1101 GPU and selectivities of 57.6 for CO 2 /N 2 and 48.6 for CO 2 /CH 4 , both of which remain stable for at least 120 h. This work demonstrates a scalable strategy for fabricating crystalline porous membranes with exotic surface structures and improved performance for industrial gas separation.