biostudies-literatureNemeth TSwiss National Science Foundation15606-15616https://www.ebi.ac.uk/biostudies/studies/S-EPMC9512017biostudies-literatureUnknown126(37)Sulfonated aromatic hydrocarbon-based ionomers are potential constituents of next-generation polymer electrolyte fuel cells (PEFCs). Widespread application is currently limited due to their susceptibility to radical-initiated oxidative degradation that, among other intermediates, involves the formation of highly reactive aromatic cation radicals. The intermediates undergo chain cleavage (dealkylation/dearylation) and the loss of protogenic sulfonate groups, all leading to performance loss and eventual membrane failure. Laser flash photolysis experiments indicated that cation radicals can also be formed <i>via</i> direct electron ejection. We aim to establish the major degradation pathway of proton-exchange membranes (PEMs). To this end, we irradiated aqueous solutions of phenyl sulfonate-tThe journal of physical chemistry. C, Nanomaterials and interfacesEPR Study on the Oxidative Degradation of Phenyl Sulfonates, Constituents of Aromatic Hydrocarbon-Based Proton-Exchange Fuel Cell Membranes.PMC9512017175493Nemeth TAgrachev MNauser TJeschke GGubler LfalseEPR Study on the Oxidative Degradation of Phenyl Sulfonates, Constituents of Aromatic Hydrocarbon-Based Proton-Exchange Fuel Cell Membranes.Sulfonated aromatic hydrocarbon-based ionomers are potential constituents of next-generation polymer electrolyte fuel cells (PEFCs). Widespread application is currently limited due to their susceptibility to radical-initiated oxidative degradation that, among other intermediates, involves the formation of highly reactive aromatic cation radicals. The intermediates undergo chain cleavage (dealkylation/dearylation) and the loss of protogenic sulfonate groups, all leading to performance loss and eventual membrane failure. Laser flash photolysis experiments indicated that cation radicals can also be formed <i>via</i> direct electron ejection. We aim to establish the major degradation pathway of proton-exchange membranes (PEMs). To this end, we irradiated aqueous solutions of phenyl sulfonate-t2022-01-01T00:00:00Z2022 Sep2026-05-28T02:14:52.802Z2024-11-06T07:53:10.135ZS-EPMC95120173617631610.1021/acs.jpcc.2c04566