Highly Hydrophilic Zirconia Composite Anion Exchange Membrane for Water Electrolysis and Fuel Cells

To prepare anion exchange membranes with high water electrolysis and single fuel cell performance, an inorganic-organic composite (IOC) strategy with click cross-linked membranes coated with different contents of hydrophilic polar nanozirconia is proposed to fabricate composite membranes (CM) PBP-SH-Zrx. The performance test results showed that the CM PBP-SH-Zr4 not only has good through-plane ionic conductivity (167.7 mS cm(-1), 80 C-degrees), but also exhibits satisfactory dimensional stability (SR 16.5%, WU 206.4%, 80 C-degrees), especially demonstrating excellent alkaline stability with only 16% degradation (2 M NaOH for 2200 h). In water electrolysis, the "microgap" between the membrane and catalyst layer (solid-solid interface) is alleviated, and the membrane electrode assembly (MEA) interfacial compatibility (liquid-solid-solid interface) is enhanced. The CM PBP-SH-Zr4 showed the lowest charge transfer resistance (R-ct, 0.037 Omega cm(2)) and a high current density of 2.5 A cm(-2) at 2.2 V, while the voltage drop was 0.361 mV h-1 after 360 h of endurance (six start-stop cycles) at 60 C-degrees and 500 mA cm(-2), proving a good water electrolysis durability. Moreover, an acceptable peak power density of 0.464 W cm(-2) at 80 C-degrees is achieved in a H-2/O-2 fuel cell with a PBP-SH-Zr4-AEM. Therefore, the IOC strategy can enhance the membrane's comprehensive performance and interface compatibility of MEA and may promote the development of anion exchange membranes (AEMs) for water electrolysis and fuel cells.