Dataset of "Operando and post-mortem study of iridium-decorated titanium-based catalysts in PEM water electrolysis"

In this work, operando Small- and Wide-Angle X-ray Scattering (SAXS/WAXS) are employed to monitor the real-time structural evolution of Ir nanoparticles supported on TiO2, TiC, and TiN in MEAs undergoing Accelerated Stress Testing (AST) in a full PEMWE. Complementary post-mortem analyses, including Transmission Electron Microscopy (TEM), Energy-Dispersive X-ray spectroscopy (EDX), XPS, and XAS, are used to correlate nanoscale morphological changes with chemical and structural transformations of the supports. By combining operando and post-mortem characterization, this study elucidates the interplay between Ir nanoparticle evolution, support degradation, and overall OER performance.