Comparison of Materials as Oxygen Catalytic Electrodes on Zirconia Electrolyte

Abstract

A study has been conducted on the effects of electrode materials on the kinetics of the oxygen reaction at electrodes on zirconia at 1000°C in air. Single point contact electrodes were used to overcome differences in morphologies of porous electrodes. The areas of contacts were calculated from the electrolyte resistance considering the electrode/electrolyte interface as a disk. The dimensions of the disk were used to normalize the currents observed at −100 mV potential as current per unit length of disk perimeter. These specific currents varied by nearly three orders of magnitude for the metals and oxides tested demonstrating the importance of the catalytic nature of the electrode material and its surface. Impedance measurements at zero overpotential showed a much smaller dependence on the electrode materials.