Semi-Interpenetrating Network Anion Exchange Membranes by Thiol–Ene Coupling Reaction for Alkaline Fuel Cells and Water Electrolyzers

In this work, a thiol–ene coupling reaction was employed to prepare the semi-interpenetrating polymer network AEMs. The obtained QP-1/2 membrane exhibits high hydroxide conductivity (162.5 mS cm(−1) at 80 °C) with a relatively lower swelling ratio, demonstrating its mechanical strength of 42 MPa. This membrane is noteworthy for its improved alkaline stability, as the semi-interpenetrating network effectively limits the attack of hydroxide. Even after being treated in 2 M NaOH at 80 °C for 600 h, 82.5% of the hydroxide conductivity is maintained. The H(2)/O(2) fuel cell with QP-1/2 membrane displays a peak power density of 521 mW cm(−2). Alkaline water electrolyzers based on QP-1/2 membrane demonstrated a current density of 1460 mA cm(−2) at a cell voltage of 2.00 V using NiCoFe catalysts in the anode. All the results demonstrate that a semi-interpenetrating structure is a promising way to enhance the mechanical property, ionic conductivity, and alkaline stability of AEMs for the application of alkaline fuel cells and water electrolyzers.