Following Facet-Resolved Shape- and Composition-Changes of Single PdPt Nanoparticles During Methane Oxidation by Operando CXDI

Methane plays a crucial role in the energy transition. As it is the second most abundant anthropogenic greenhouse gas, it is crucial to ensure a complete oxidation of CH4 to CO2 and H2O. Already commercially in use, PdPt catalysts were found to be highly active for CH4 oxidation with a reported conversion of 10% at a temperature of only 200°C. From ensemble averaging experiments it is difficult to determine the nanoparticle near surface composition, which is detrimental for the establishment of structure – activity relationships. We therefore propose to use operando Coherent X-ray Diffraction Imaging (CXDI) to follow the structural evolution of single PdPt NPs during CH4 oxidation. We aim to relate shape and facet-resolved strain state changes in single NPs to the catalytic activity. Furthermore, we intent to identify NP surface facet sites and strain related surface compositions most relevant for methane oxidation for NPs with initial core-shell and alloy configuration.