On the Radical-Induced Degradation of Quaternary Ammonium Cations for Anion-Exchange Membrane Fuel Cells and Electrolyzers.

ABSTRACT: Four benzylic-type quaternary ammonium (QA) compounds with different electron density at the phenyl group were evaluated for their susceptibility against degradation by radicals. Time-resolved absorption spectroscopy indicated that radicals with oxidizing and reducing character were formed upon oxidation by HO⋅ and O⋅^- (conjugate base of HO⋅). It was estimated that, dependent on the QA, 18-41 % of the formed radicals were oxidizing with standard electrode potentials (E⁰ ) above 0.276 V and 13-23 % exceeded 0.68 V, while 13-48 % were reducing with E⁰ <-0.448 V. The stability of these model compounds against oxidation and reductive dealkylation was evaluated at both neutral and strongly alkaline conditions, pH 14. Under both conditions, electron-donating grou

SUBMITTER: Nemeth T 

PROVIDER: S-EPMC9828592 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature