SIMS METHODS IN REACTIVITY STUDIES ON METAL-OXIDES

A SIMS (secondary ion mass spectrometry) study of IrO2RuO2TiO2, mixed oxide films and PbO2 films synthesized by thermal and electrochemical processes, respectively, reveals interesting cluster ions that may be very important in evaluating component reactivity between different me tal oxides and with trapped ions or neutral particles present in the d ifferent matrices. The ion yields of clusters are also strongly affect ed by the presence of minor components, and the examples reported in t his paper confirm that mass spectra and ion profiles can give a better characterization of the surface region and help in understanding modi fications that affect some catalytic or electrocatalytic aspects. The various oxidation states of metals contained in the ion species, and t he formation of oxides or fragmentations, give unequivocal and importa nt responses to problems of applied research on inorganic materials. T he present paper presents evidence that a large amount of data can be obtained by SIMS and further studies are in progress to probe fundamen tal aspects and possible relations between surface mass spectra and su rface chemistry.