Pioneering operando XRD and XAS as novel tools to probe the temperature in metal nanoparticle catalysts.

During catalytic reactions, heat is released on or extracted from the catalyst. This leads to strong catalyst temperature changes, on its turn triggering restructuring and undesired side reactions. Here, XRD will be pioneered as novel tool in combination with XAS to probe the temperature of metal nanoparticles and the support for the first time selectively and operando in real-time. By monitoring the changes in the lattice spacing (XRD) and the Debye-Waller factor (XAS), thermally induced lattice expansion/disorder will be linked to the temperature. This will enable to unravel temperature heterogeneities in the catalyst, chart heat transport and reaction rates, and in general provide a first-of-its-kind temperature bookkeeping in catalysis.