Electrochemical permeability of GCO: Estimation of overpotentials

The basic relationships required to analyse permeability data of fluorite-based solid electrolytes are rewritten in order to account for an overpotential term related to slow surface exchange. Results of a gadolinia doped ceria solid electrolyte suggest that surface exchange might limit the permeability especially at low Po₂ and temperature. However, the analysis of the data with different relationships leads to somewhat different estimates of the electron and hole conductivity and overpotential values. Paper presented at the 5th Euroconference on Solid State Ionics, Benalmádena, Spain, Sept. 13–20, 1998