High-performance twisted ether-free polymer based anion exchange membranes with crown ether units

Crown ether, as a hydrophilic group, is capable of forming complexes with metal cations and serves as a key component for constructing supramolecular assemblies. This functionality allows it to dynamically capture anchor points, enhance ion aggregation, and improve the hydroxide conductivity. However, the high hydrophilicity of crown ether can lead to excessive swelling, which limits its application. Therefore, this study designs ether-free AEMs containing crown ether, m-terphenyls and piperidine through superacid-catalyzed synthesis, and are used in fuel cells. PMDTP-15 not only achieves efficient conduction of OH − (130.7 mS·cm −1 , 80 °C), but also effectively limits the swelling of the membrane (19.1 %, 80 °C) and exhibits excellent alkali stability (after being immersed in 1 M NaOH solution for 1680 h, the conductivity remained 95.34 %, and the mechanical properties decreased by 1.13 %) due to the high hydrophilicity and m-terphenyl torque structure of the crown ether structure. In addition, the peak power density of a single PMDTP-15 cell can reach 1043 mW·cm −2 , and the voltage can maintain 90 % of the original performance after 120 h.