Two papers on particle size effect on platinum dissolution
23/06/2020 - Recent works are published in ACS Catalysis and ACS Appl. Mater. Interfaces
Article 1 title: Particle Size Effect on Platinum Dissolution: Considerations for Accelerated Stability Testing of Fuel Cell Catalysts
Authors: Daniel J. S. Sandbeck, Niklas Mørch Secher, Florian D. Speck, Jakob Ejler Sørensen, Jakob Kibsgaard, Ib Chorkendorff, and Serhiy Cherevko
Article 2 title: Particle Size Effect on Platinum Dissolution: Practical Considerations for Fuel Cells
Authors: Daniel J. S. Sandbeck, Masanori Inaba, Jonathan Quinson, Jan Bucher, Alessandro Zana, Matthias Arenz, and Serhiy Cherevko
Proton exchange membrane fuel cells (PEMFC) suffer from high cost of the state of the art platinum catalyst. The PEMFC costs can be reduced by decreasing the size of Pt nanoparticles in the catalyst layer, thereby increasing the Pt dispersion and utilization. However, firm conclusions on how Pt particle size impacts durability remain elusive due to synthetic difficulties in exclusively varying single parameters (e.g., particle size and loading). To address these issues, two model systems were synthesized and studied in collaboration with Prof. Arenz and Prof. Chorkendorff groups. 2D system was prepared by depositing mass-selected nanoparticles on a flat glassy carbon substrate using magnetron sputtering. Pt particle diameter was varied from 2 to 10 nm. A complex interplay between dissolution and passivation processes (both depend on particle size) was identified. As for 3D system, the particle size of Pt nanoparticles was varied from 2.0 to 2.8 and 3.7 nm while keeping the loading constant (30 wt %) on a Vulcan support using the two-step surfactant-free toolbox method. In this study we found that the transient mechanism of Pt dissolution is independent on particle size, while onsets of dissolution shifts to more anodic potentials for particles with larger diameters.
More details can be found in manuscripts, which can be accessed at
ACS Catalysis - https://pubs.acs.org/doi/10.1021/acscatal.0c00779 and
ACS Appl. Mater. Interfaces - https://pubs.acs.org/doi/10.1021/acsami.0c02801.