(Digital Presentation) Investigation of the Active Site on Rhodium Oxide for the Oxygen Reduction Reaction Using In-Situ XAFS

Abstract

The quasi-steady-state current values and XANES spectra of Rh2O3 were investigated using the in-situ XAFS method to understand the adsorption state of oxygen molecules on the surface. It was suggested that the adsorption of oxygen molecules on the Rh2O3 surface was rapid in the low-potential region where the oxygen reduction reaction proceeds sufficiently. In addition, it was suggested that the adsorption state of oxygen molecules might be different from that of the high potential region where the oxygen reduction reaction did not proceed. XANES spectra also showed that the valence of Rh atoms in Rh2O3 remained high, independent of oxygen partial pressure.