Corrosion of Mo in KOH: Time resolved XAFS investigations

The corrosion products formed during the anodic polarization of molybdenum in 1 M KOH were investigated in situ with time-resolved X-ray absorption sp ectroscopy at the Mo K-edge. Near edge spectra (XANES) as well as EXAFS sca ns extending over approximately 1000 eV above the Mo absorption edge were m easured as a function of the corrosion time. Time dependent values for the concentration of the dissolved Mo species in the electrolyte were calculate d from the change of the absorption cofficient at the absorption edge. The detailed analysis of the XANES and EXAFS data suggests the presence of MoO4 2- ions in the solution.