Sandwich‐Like Free‐Standing Covalent Organic Framework Anion Exchange Membranes for Water Electrolysis

). Furthermore, the rigid and hydrophobic COF core effectively mitigates the membrane swelling ratio (SR) (5.2% @ 80 °C), while its combination with the flexible hydrophilic polymer skin enhances the robustness of the COF-AEM simultaneously, achieving a tensile strength of 21.4 MPa. Demonstrated in alkaline water electrolysis, this represents the first free-standing COF-AEM for such applications. Our design expands COF-AEM structural diversity, offering a promising approach for advanced ion-conductive materials.