Dual-structure, dual-function mixed matrix membrane for alkaline water electrolysis

As a critical component in alkaline water electrolyzers, the separator plays a vital role in overall performance. To overcome the limitations of traditional separators (e.g., low ionic conductivity and insufficient alkaline stability), this study proposes an innovative "pre-embedded monomer-interfacial polymerization" strategy and develops a novel dual-structure, dual-function polymer electrolyte membrane. This membrane achieves simultaneous optimization of stability and conductivity by in situ constructing a uniform QA crosslinked network within the ISM matrix via the Menshutkin reaction. synergistically integrating the alkali stability of ISM with the efficient ion transport properties of AEM. The optimized membrane (POBP-PMDETA-4) exhibited high ionic conductivity (92.3 mS/cm at 70 °C), high electrolyte uptake (101.83%), good hydrophilicity (42.2°), and excellent performance in AWE,achieving 2.01 V at a current density of 0.4 A/cm 2 with stable operation for 346 h. This study offers a promising strategy for designing high-performance, durable separators for advanced alkaline water electrolysis.