Journal of the American Chemical Society · 2015 · 447 citations · 151 references
EngineeringStructure–stability RelationshipsChemistryInorganic CompoundChemical EngineeringProton-exchange MembraneHighest Alkaline StabilitiesAnion SensingMaterials ScienceInorganic ChemistrySolid-state IonicAlkaline StabilityBiochemistryImidazolium CationsCrystallographyElectrochemistryExceptional Alkaline StabilityNatural SciencesIonic ConductorAlkaline Fuel CellsIon Structure
Highly base-stable cationic moieties are a critical component of anion exchange membranes (AEMs) in alkaline fuel cells (AFCs); however, the commonly employed organic cations have limited alkaline stability. To address this problem, we synthesized and characterized the stability of a series of imidazolium cations in 1, 2, or 5 M KOH/CD3OH at 80 °C, systematically evaluating the impact of substitution on chemical stability. The substituent identity at each position of the imidazolium ring has a dramatic effect on the overall cation stability. We report imidazolium cations that have the highest alkaline stabilities reported to date, >99% cation remaining after 30 days in 5 M KOH/CD3OH at 80 °C.
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