CHARACTERIZATION OF RUO2-BASED FILM ELECTRODES BY SECONDARY-ION MASS-SPECTROMETRY

Concentration depth profiles of Ti-supported RuO2-TiO2 films, prepared by pyrolysis of ruthenium(III) chloride hydrate and titanium diisopro poxide bis-pentane-2,4-dionate, have been studied by secondary ion mas s spectrometry (SIMS). The Ru-102:Ti-48 ion intensity ratio vs. the no minal concentration of ruthenium oxide was followed for samples obtain ed from precursors dissolved in different solvents. The dependence on bombarding time of ion intensity profiles for other species, such as O - (m/z = 16), OH- (m/z = 17), (TiO+)-Ti-46 (m/z = 62), (TiOH+)-Ti-50 ( m/z = 63) was also studied. The mixed oxide films were characterized b y cyclic voltammetry. The results of the combined research support the idea that microstructural and chemical impurities are concentrated in the outermost part of the film. This phenomenon seems to depend on th e composition of the solvent used for the precursor salts.