Anion exchange membranes with orderly channels enabled by charge transfer interactions for fast transportation of Cl−

Abstract

The formation of an ordered microphase separation structure and the realization of efficient selective ion conduction by precise regulation of the self-assembly process of solid ionic conductive polymers are important in the fields of batteries and electrodialysis. To prepare ion exchange membranes with high conductivity and selectivity, we report a strategy for the design of a selective directional self-assembly backbone by the introduction of charge transfer interactions. Fluorescence spectroscopy (FL) and nano-scale microscopy analysis confirmed the self-assembly of the backbone with charge transfer interactions which resulted in good microphase separation structures for fast transportation of Cl−. The obtained QP(NDIB/PyB)-1 anion exchange membrane (AEM) showed the highest chloride ion conductivity of 83 mS cm−1 (80 °C). In addition, the selectivity of QP(NDIB/PyB)-X was verified by separation experiments of Cl− and SO42‐ (PSO42‐Cl‐ = 21.8). This introduction of electron transfer interactions into polymer structures is expected to contribute to the expansion of ion channel construction strategies and the development of ion-exchange membranes.