Formation and Decomposition of Thin Rhodium Oxide Films
Reaction Kinetics and Catalysis Letters
, E-ISSN: 1588-2837
Boreskov Institute of Catalysis, 630090 Novosibirsk Russia
Interaction of O2 with Rh (poly) and Rh (100) has been studied by Auger Electron Spectroscopy and thermal desorption method at O2 pressures of 10−5 – 103 Pa and at 400–1600 K. At P(O2)<10−5 Pa chemisorption of O2 occurs, at
P(O2)=10−5 – 10−1 Pa surface oxides are formed, at P(O2)>1.0 Pa a bulk Rh2O3 oxide starts to grow. The growth of rhodium oxide film proceeds via the Cabrera-Mott mechanism. Its decomposition occurs via a mechanism including electron transfer across the oxide film, O2 desorption from the surface layer and rearrangement of the oxide layer.