LOW-TEMPERATURE OXYGEN-ELECTRODE REACTION ON BISMUTH RUTHENIUM OXIDESSTABILIZED ZIRCONIA/

Bi2Ru2O7 and Bi3Ru3O11, have been tested as electrodes on stabilized z irconia at temperatures as low as 500 K. The oxides have been characte rized by thermogravimetry under controlled oxygen partial pressure at high temperature and by potentiometric measurements after controlled c athodic polarization. The oxygen electrode reaction as functions of ox ygen pressure and temperature has been studied by impedance spectrosco py. At low temperature, the dependence of the polarization resistance on the oxygen pressure was analyzed in terms of charge transfer as a r ate controlling step. (C) 1998 Elsevier Science B.V. All rights reserv ed.