title: Dissolution of Platinum in the Operational Range of Fuel Cells.
abstract: One of the most important practical issues in low-temperature fuel-cell catalyst degradation is platinum dissolution. According to the literature, it initiates at 0.6-0.9 VRHE, whereas previous time- and potential-resolved inductively coupled plasma mass spectrometry (ICP-MS) experiments, however, revealed dissolution onset at only 1.05 VRHE. In this manuscript, the apparent discrepancy is addressed by investigating bulk and nanoparticulated catalysts. It is shown that, given enough time for accumulation, traces of platinum can be detected at potentials as low as 0.85 VRHE. At these low potentials, anodic dissolution is the dominant process, whereas, at more positive potentials, more platinum dissolves during the oxide reduction after accumulation. Interestingly, the potential and time dissolution dependence is similar for both types of electrode. Dissolution processes are discussed with relevance to fuel-cell operation and plausible dissolution mechanisms are considered.
authors.affiliation: Department of Interface Chemistry and Surface Engineering Max-Planck-Institut für Eisenforschung GmbH Max-Planck-Straße 1 40237 Düsseldorf Germany.
authors.forename: Serhiy
authors.initials: S
authors.lastname: Cherevko
authors.affiliation: Department of Interface Chemistry and Surface Engineering Max-Planck-Institut für Eisenforschung GmbH Max-Planck-Straße 1 40237 Düsseldorf Germany.
authors.forename: Gareth P
authors.initials: GP
authors.lastname: Keeley
authors.affiliation: Department of Interface Chemistry and Surface Engineering Max-Planck-Institut für Eisenforschung GmbH Max-Planck-Straße 1 40237 Düsseldorf Germany.
authors.forename: Simon
authors.initials: S
authors.lastname: Geiger
authors.affiliation: Department of Interface Chemistry and Surface Engineering Max-Planck-Institut für Eisenforschung GmbH Max-Planck-Straße 1 40237 Düsseldorf Germany.
authors.forename: Aleksandar R
authors.initials: AR
authors.lastname: Zeradjanin
authors.affiliation: Department of Interface Chemistry and Surface Engineering Max-Planck-Institut für Eisenforschung GmbH Max-Planck-Straße 1 40237 Düsseldorf Germany.
authors.forename: Nejc
authors.initials: N
authors.lastname: Hodnik
authors.affiliation: Department of Interface Chemistry and Surface Engineering Max-Planck-Institut für Eisenforschung GmbH Max-Planck-Straße 1 40237 Düsseldorf Germany.
authors.forename: Nadiia
authors.initials: N
authors.lastname: Kulyk
authors.affiliation: Department of Interface Chemistry and Surface Engineering Max-Planck-Institut für Eisenforschung GmbH Max-Planck-Straße 1 40237 Düsseldorf Germany.
authors.forename: Karl J J
authors.initials: KJ
authors.lastname: Mayrhofer
keywords: electrochemistry; energy conversion; fuel cells; mass spectrometry; platinum