Anion exchange membranes with well-defined ion transporting nanochannels via self-assembly of polymerizable ionic liquids

Abstract

In this study, we present a facile method to construct highly ordered and well-defined ionic channels in anion-exchange membranes (AEMs) through in-phase photopolymerization of liquid crystals (LCs). Hexagonal and lamellar LC samples were prepared by the self-organization of polymerizable amphiphilic imidazolium-based ionic liquids. The preservation of LC nanostructures in the obtained polymeric membranes was confirmed by the combination of small-angle X-ray scattering (SAXS), polarized optical microscope (POM), and scanning electronic microscopy (SEM) measurements. Phase separations of LCs at the molecular level provided highly ordered and well-defined ionic channels for efficient anion conduction and meanwhile maintained a strong hydrophobic domain to suppress the swelling degree. The membranes synthesized in the present work provide a promising model system for understanding the idea of constructing ionic highways in AEMs through self-organization.