A study of factors that influence zirconia/platinum interfacial impedance using equivalent circuit analysis

An equivalent circuit model based on complex impedance analysis was proposed to characterize the zirconia electrochemical cell, and to correlate the performance of the cell with the material set and processing parameters. The empirical model that emerged is an extension of previous models [1.2] and was derived from a series of fabrication experiments. The resulting model can be used to describe the conduction mechanisms of zirconia grain and grain boundaries, along with components of the zirconia/platinum interfacial and electrode conduction, the porosity and roughness of the electrode, and the diffusion characteristics within electrode and at the interface. The model can be utilized to predict the performance of the zirconia cell, and to gain a better understanding of the impact of the materials and processing parameters so as to optimize the fabrication process for planar-type sensors. (C) 2001 Published by Elsevier Science B.V.