CAST AQUIVION® POLYMER ELECTROLYTE MEMBRANES CONTAINING CE-BASED SCAVENGERS AS DEGRADATION MITIGATING AGENTS IN PEMFCS: STANDARDISED CASTING METHOD AND PROPERTIES

Cast Polymeric electrolyte membranes based on a commercial Aquivion® polymer dispersion (D72- 25BS; EW=720g/eq) by Syensqo were cast by a standardised casting technique to be used in H2/air PEMFCs. Aquivion® polymer dispersions are a copolymer of Tetra Fluoro Ethylene (TFE) and Sulfo- nyl Fluoride Vinyl Ether (SFVE), frequently named as Short-Side-Chain (SSC) ionomer with a higher Ion Exchange Capacity (IEC) and Proton Conductivity (PC) than Long-Side-Chain (LSC) perfluoro- sulphonic ones. A self-made 30% Pt/CeO2 synthesized by a colloidal method, particularly by an im- pregnation method of a commercial CeO2 over a Pt sulphite precursor, was prepared and used as a radical scavenger (RS) in different loadings. A commercial pure CeO2 was used as a reference in membrane. Aquivion® membranes with RS were cast with the aim to investigate the well- known mitigating effect on peroxidic and characterised in order to study the improvement of the electro- chemical performance. Chemical-physical characterisations and the electrochemical behaviour in a PEMFC were investigated in order to evidence the improved properties and understand the possible degradation mechanism. At the end, the developed membranes were compared to pilot-scale e-PTFE reinforced Aquivion® membranes by Syensqo to evaluate the improvements.