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Fenton Stability of Mesoporous Ceria-Silica and Its Role in Enhanced Durability of Poly(arylene ether sulfone) Multiblock Copolymer Composite Membranes for Perfluorosulfonic Acid Alternatives.

ABSTRACT: To increase the stability of cerium scavengers, we doped cerium oxide on mesoporous silica powders for the application of an oxidative stabilizer. The oxidation-reduction reaction involving hydroxyl radicals (^•OH) is investigated with Fenton's test using eight types of Ce(IV)-mobile compositions of matter 41 (MCM-41) and Ce(III)-MCM-41 powder samples. As confirmed by X-ray photoelectron spectroscopy, the relative amount of Ce³⁺ inside the mesoporous samples decreases with the increasing time of treatment using the Fenton solution, whereas that of Ce⁴⁺ increases. ²⁹Si CP-MAS NMR shows that the condensation of the siloxane bond varies according to the treating time up to 120 h. The mesoporous structure is also analyzed using synchrotron small-angle X-ray scattering and nitrogen adsorption. Further treatment with propane sulfonic acid ensured that the ionic conductivity of the sulfonated mesoporous silica did not decrease. The surface-modified mesoporous silica was incorporated in sulfonated poly(arylene ether sulfone) multiblock membranes. The sulfonated mesoporous silica could overcome the drawbacks of transition metal scavengers, such as a drop in ionic conductivity. Through experiments, we determined that the Ce-doped sulfonated mesoporous silica/sulfonated poly(arylene ether sulfone) composite membranes exhibit high oxidation stability when exposed to hydrogen peroxide and even higher proton conductivity than Nafion at a relative humidity over 60%.

SUBMITTER: Kim J

PROVIDER: S-EPMC8495844 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Sulfonated Poly(Arylene Ether Sulfone) and Perfluorosulfonic Acid Composite Membranes Containing Perfluoropolyether Grafted Graphene Oxide for Polymer Electrolyte Membrane Fuel Cell Applications.

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