ELECTROLYSE DE LA VAPEUR D'EAU A HAUTE TEMPERATURE ETUDE DU DOPAGE DE L'INTERFACE CATHODIQUE
This work dealt with the improvement of the water vapour reduction in stabilized zirconia based cells by doping the cathode interface with Ce**4+/Ce**3+ redox couple. A preparation technique of such an interface transposable to an industrial scale is proposed. It consists in coating porous zirconia substrates by spraying a dilution of ceria in water prior to high temperature sintering. Automatisation of the spraying phase guarantees the homogeneity and reproducibility of the layer. The catalytic activity of the doped interface has been studied by impedance spectroscopy in dynamic conditions. Besides the nature of the electrode material, the temperature, the concentration of the vapour, the major parameter of the study was the concentration in cerium. It has been shown that the maximum efficiency of the doped interface was obtained for a concentration in cerium ranging between 4 and 10 weight percent. The results has been analyzed by considering the relative contribution of the ionic and electronic conductivities of the electrolyte surface. The stability of the doping effect has been studied with respect to time, current density and repeated oxydo-reduction cycling.
Références bibliographiques: EUR 9775 FR (1985) MF, 72 P., BFR 150, BLOW-UP COPY BFR 360, EUROFFICE, LUXEMBOURG, POB 1003
Disponibilité: Can be ordered online
Numéro d'enregistrement: 1989123076500 / Dernière mise à jour le: 1987-01-01
Langues disponibles: fr