J. Phys. IV France 7 (1997) C2-727-C2-729
In Situ XAFS Investigation on the Oxidation of Cu Foils at T > 770 KN. Hilbrandt1, R. Frahm2 and M. Martin1
1 Institute for Physical Chemistry, Electrochemistry, TH Darmstadt, Petersenstr. 20, 64287 Darmstadt, Germany
2 HASYLAB at DESY, Notkestr. 85, 22603 Hamburg, Germany
Serving as a model reaction for high temperature solid state investigations, the oxidation of copper metal foil to the corresponding oxides Cu2O and CuO was studied for the first time by means of QEXAFS and DEXAFS spectroscopy. These techniques allow us to follow the solid state reaction in situ and time resolved, after changing the oxygen activity at elevated temperature (770 K < T <1100 K). The overall reaction can be described by a two-step-mechnism with the Cu2O-phase to be formed intermediately. XRD measurements performed ex situ at different reaction times coincide with these results. Involving a least-square refinement of the XANES-spectra the phase amounts of Cu, Cu2O and CuO were determined with high accuracy to characterise the reaction kinetics.
© EDP Sciences 1997