New paper online: Pt dissolution in realistic fuel cell catalyst layers
06/01/2021 - Recent work is published in Angewandte Chemie.
Article title: Pt dissolution in realistic fuel cell catalyst layers
Authors: Konrad Ehelebe, Julius Knöppel, Markus Bierling, Britta Mayerhöfer, Thomas Böhm, Nadiia Kulyk, Simon Thiele, Karl Mayrhofer, Serhiy Cherevko
Our new work on Pt dissolution in realistic fuel cell catalyst layers was published in Angewandte Chemie. In this current work we present the first experimental approach to measure Pt dissolution in gas diffusion electrodes (GDE). Therefore we coupled our GDE half-cell setup with inductively coupled plasma mass spectrometry (ICPMS). With this, Pt dissolution in realistic catalyst layers and the transport of dissolved Pt species through Nafion membranes are evaluated directly.
We hereby observe that (i) specific Pt dissolution is increasing significantly with decreasing Pt loading, (ii) in comparison to experiments on aqueous model systems with flow cells, the measured dissolution in GDE experiments is considerably lower and, (iii) by adding a membrane onto the catalyst layer, Pt dissolution is reduced even further. All these phenomena can be attributed to the varying mass transport conditions of dissolved Pt species, influencing re-deposition and equilibrium potential. With the presented method we were also able to measure the diffusion coefficient of Pt species in Nafion, which can be of great importance when modelling fuel cell degradation.