Electronic state of ruthenium deposited onto oxide supports: An XPS study taking into account the final state effects

► The chemical state of Ru in the Ru/oxide catalysts was examined by XPS. ► The experimental binding energies of supported Ru were corrected for the differential charging and relaxation effects. ► The initial state energies of Ru atoms in the Ru/oxide catalysts were found identical regardless of acid-base properties of the support. ► Metallic Ru deposited on MgO, γ-Al2O3 and SiO2 is characterized by a deficit of electron density.