Abstract
The oxidation-reduction kinetics of Pd was investigated on polycrystalline Pd foils using XPS and sputter-depth profiling over a wide range of temperatures. The observed behavior can be explained in terms of a desorption-controlled process at lower temperatures (T < 230°C) and a diffusion-controlled process at higher temperatures (T > 450°C). In the intermediate range (230 < T < 450°C) a transition between the two processes is observed which gives rise to a pronounced shoulder in the reduction time trace. The interpretation is qualitatively confirmed using a simple mathematical model for a coupled bulk diffusion/surface reaction system.
Original language | English (US) |
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Pages (from-to) | 199-206 |
Number of pages | 8 |
Journal | Catalysis Letters |
Volume | 58 |
Issue number | 4 |
DOIs | |
State | Published - Apr 1999 |
Bibliographical note
Funding Information:GV gratefully acknowledges financial support through a fellowship of the Deutsche Forschungsgemeinschaft, as well as the hospitality of the Surface Analysis Center at the University of Minnesota.
Keywords
- Oxidation-reduction
- Palladium
- Reaction-diffusion model
- Sputter-depth profiling
- XPS