%0 Journal Article %T Measurement and adjustment of proton activity in solid polymer electrolytes %+ IFP Energies nouvelles (IFPEN) %A Edward, Brightman %A Pasquier, David %< avec comité de lecture %@ 1388-2481 %J Electrochemistry Communications %I Elsevier %V 82 %P 145 - 149 %8 2017-09 %D 2017 %R 10.1016/j.elecom.2017.08.005 %K Ionomers %K pH %K proton activity %K polymer electrolyte membrane %K reference electrode %Z Chemical SciencesJournal articles %X Technological progress in electrochemical energy conversion devices requires new solid polymer electrolyte membrane (PEM) materials with particular properties. The strongly acidic nature of Nafion® is not always desirable; for instance, CO2 electroreduction requires a low proton activity to avoid excess hydrogen evolution. This communication presents a novel measurement technique for determining the acidity of a PEM, using a pH-sensitive electrode half-cell attached to the membrane sample, connected to a reference electrode via a salt bridge. A dynamic hydrogen electrode on platinized‑platinum surface (DHE) was found to give repeatable results within 5% uncertainty. Several membranes based on Nafion® impregnated with various basic species were tested, as well as an anion-exchange membrane and a poly-phosphonic acid membrane. The technique is expected to have wider reaching applications in PEM fuel cell and redox flow battery development, as well as in the electrolysis and electrodialysis industries. %G English %2 https://ifp.hal.science/hal-01701111/document %2 https://ifp.hal.science/hal-01701111/file/Pasquier%202017.pdf %L hal-01701111 %U https://ifp.hal.science/hal-01701111 %~ IFP