Towards atomistic understanding of platinum dissolution.
Article title: Dissolution of Platinum Single Crystals in Acidic Medium
Authors: Daniel J. S. Sandbeck, Dr. Olaf Brummel, Prof. Dr. Karl J. J. Mayrhofer, Prof. Dr. Jörg Libuda, Dr. Ioannis Katsounaros, Dr. Serhiy Cherevko.
Modern fuel cells rely on platinum and platinum alloy electrocatalysts to catalyze both hydrogen oxidation and oxygen reduction reactions. During fuel cell operation, such catalysts can experience high anodic potentials, which will result in the dissolution of platinum. As an outcome of extensive experimental research performed over the last decade, including our on-line ICP-MS works, e.g. see our review (http://dx.doi.org/10.1016/j.nanoen.2016.03.005), dissolution of platinum on the macroscale has become well understood. On the other hand, atomistic understanding is still lacking. For this, in the study by Sandbeck et al., Pt single crystals were prepared and analyzed using on-line SFC-ICP-MS (see Figure showing CVs of different Pt single crystals). More details can be found online - https://doi.org/10.1002/cphc.201900866.
The current paper can be considered as one of the first Pt dissolution works required to understand how oxidation processes on the Pt surface lead to Pt leaving the lattice and result in the macroscopically observed dissolution. It quantifies Pt dissolution from different low indices Pt single crystals. Works have begun on bringing these results together with experimental data on Pt oxidation (surface synchrotron XRD, collaboration with Prof. Dr. Olaf Magnussen and Dr. Jakub Drnec) and theoretical mechanistic DFT studies on Pt extraction from the lattice (collaboration with Dr. Federico Calle-Vallejo). See updates on our homepage!