Project Details
Projekt
Mechanisms of the electrochemical oxidation, restructuring, and dissolution of platinum and other noble metals
Subject Area
Physical Chemistry of Solids and Surfaces, Material Characterisation
Experimental Condensed Matter Physics
Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
Experimental Condensed Matter Physics
Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
Term
since 2026
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 563512805
The project aims at a better understanding of the electrochemical oxidation and the associated dissolution of platinum and related noble metals in order to develop methods for the mitigation of these processes. This topic is of substantial fundamental interest as well as of high technological relevance for reducing Pt catalyst degradation in electrochemical devices, such as fuel cells. In our previous work we developed a research strategy based on combined high-energy surface X-ray scattering, online mass spectrometry, and density functional theory, which we applied to studies of Pt(111), Pt(100), and Pt(110) electrodes. These studies provided insights into the relationship between the atomic-scale structure of the ultrathin surface oxide, the Pt dissolution behavior, and the nanoscale restructuring of the Pt surfaces, revealing a pronounced influence of Pt surface orientation. However, major questions regarding these complex interface processes still exist, which we will address in the new project, using the developed methods and approaches as well as complementary ab initio simulations. Specifically, we will investigate the following topics: (1) We will clarify in more detail the initial stages of Pt oxidation and dissolution, as these are particularly relevant for applications. Our previous work revealed important differences in the kinetics of the oxidative formation of adsorbed oxygen species and the kinetics of Pt atom extraction out of the surface, which are currently not understood. We will clarify the origin of this discrepancy by fast time-resolved measurements and simulations. (2) We will address the role of surface defects, in particular steps, by determining their influence on the dissolution behavior and the structure of the surface oxide near steps. (3) We will further explore the mechanisms and interplay of oxide reduction, cathodic dissolution, and irreversible restructuring of the Pt surface. (4) Using the same methodology as in 1-3, we will determine how oxidation and dissolution can be influenced by electrolyte composition (pH, anion species) and the presence of organic and inorganic surface modifiers. Objective of this research is to develop a knowledge base for the controlled interface engineering of Pt electrocatalysts. (5) Finally, we will investigate whether the insights obtained on Pt can be transferred to other noble metals by performing studies of Au(111), Pd(111), and Ir(111) oxidation and dissolution.
DFG Programme
Research Grants
International Connection
Canada, France, Spain
