Electrode reactions of La0.8Sr0.2MnO3±δ-electrodes on stabilized zirconia with oxygen and the nitrogen oxides NO and NO2 |
| |
Authors: | G. Reinhardt H. -D. Wiemhöfer W. Göpel |
| |
Affiliation: | (1) Institute for Physical and Theoretical Chemistry, University of Tübingen, Germany |
| |
Abstract: | The kinetics for the electrode reactions with oxygen and with NO and NO2 in the presence of oxygen has been studied for La0.8Sr0.2MnO3±δ-electrodes on stabilized zirconia (8 mol% Y2O3=YSZ) in the temperature range between 500°C and 900°C for oxygen partial pressures between 1 kPa and 20 kPa by means of electrochemical methods (impedance, I-U characteristics) and temperature programmed desorption (TPD). For oxygen reduction below 900°C a mechanism is proposed which describes the formation of peroxidic ions at the electrode surface and a subsequent rate-determining electron transfer at the three-phase-boundary. At temperatures below 650°C the electrode reaction between NO and NO2 is much faster than the oxygen reduction. The results for the NO2-reduction to NO can be explained by a two-step mechanism consisting of a fast one-electron transfer to adsorbed NO2 at the electrode surface and a subsequent rate-determining transfer of the second electron to NO2 at the three-phase-boundary. Paper presented at the 1st Euroconference on Solid State Ionics, Zakynthos, Greece, 11 – 18 Sept. 1994 |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|