Dataset of "Capabilities of a novel electrochemical cell for operando XAS and SAXS investigations for PEM fuel cells and water electrolysers"

With this work we present a reversible electrochemical cell and introduce a valuable approach, suitable for being used either for in operando X-Ray Absorption Spectroscopy (XAS) and Small Angle X-Ray Scattering (SAXS). The reversible electrochemical cell was used to depict the time-resolved degradation of a Pt/C catalyst material for Proton Exchange Membrane Fuel Cells (PEMFC). The evolution of the specific electrochemical active surface area (ECSA) was coupled to the evolution of morphological parameters, supported by the analysis of Pt oxidation state. As a result, we obtain a coherent picture in which: the increase of particle (and particle cluster) size is connected to the diminishing of ECSA and to the changes in the fraction of metallic Pt, detailing as the evolution develops in the first 2000 cycles, as previously observed on catalyst model systems. Finally, we introduce some preliminary results underlying the change in Ir oxidation state for a commercial Ir/IrO X catalyst material for PEM water electrolysers and showing as this change is not sufficient to induce any remarkable morphological variations within 500 cycles of accelerated stress tests.