Influence of the Valve Metal Oxide on th

This study investigates the depth profiling of RuO2/TiO2 mixed oxide coatings supported on titanium foil, employing Rutherford backscattering spectrometry and x-ray photoelectron spectroscopy. The results from both techniques reveal significant surface segregation of the valve-metal oxide and a general enrichment within the first 100-150 nm of the coating. Notably, this segregation phenomenon appears to be less pronounced for coatings with ruthenium content exceeding 60 atomic percent. The type of ruthenium salt utilized during coating preparation seems to influence the degree of surface enrichment observed. Previous research indicated that surface segregation effects can reduce the surface concentration of noble-metal oxides from their nominal values, prompting a broader investigation into ruthenium oxide and titanium oxide coatings that are relevant for industrial applications. Limited information exists regarding the surface compositional features of these systems, primarily concerning 30 atomic percent Ru compositions. Existing literature has indicated surface enrichment phenomena in similar coatings; however, our findings contribute to a deeper understanding of the mechanisms at play and establish a basis for future research into mixed oxide systems utilized in electrochemistry.