Highly conductive alkaline anion exchange membrane containing imidazolium-functionalized octaphenyl polyhedral oligomeric silsesquioxane filler

Imidazolium-functionalized octaphenyl polyhedral oligomeric silsesquioxane nanoparticles were incorporated into imidazolium-functionalized poly(ether ether ketone) (ImPEEK) to fabricate high-performance anion exchange membranes with tuneable microphase separation structures and efficient ion transport channels. High-resolution transmission electron microscopy observations revealed the formation of ion channels in the membranes due to the aggregation of imidazolium groups. The transport of hydroxide ions in the composite membranes was facilitated by the increase in the effective ion mobility from 2.27×10−4 to 3.09×10−4 cm2 s−1 V−1, while their hydroxide conductivity at 30 °C (36.22-44.11 mS cm−1) was significantly higher than that of an ImPEEK control membrane (30.66 mS cm−1).