Computational Study of the Morphology of Benzimidazolium and Imidazolium Anion Exchange Membranes*

Finding suitable alternatives to unsustainable energy sources is a pressing matter considering the challenge of climate change. Hydrogen fuel cell technologies are a promising option due to their high efficiencies and energy densities. However, the traditional implementations of fuel cells have been plagued by scalability issues due to reliance on fluorine-based materials and to high costs of noble metals such as platinum. Hydrocarbon-based anion-exchange membranes (AEMs) are being developed to address these issues. We have been studying several AEM candidates using both computational and experimental techniques with a focus on ionenes, where the charge is along the polymer backbone. In this work we compare the structure and ion dynamics in membranes based on a series of benzimidazolium and imidizolum backbones using techniques such as molecular dynamics simulations and clustering analyses in order to improve our understanding of the differences between candidate membranes.