Impedance Behavior of LSCF/YDC/LSCF Symmetrical Half Cell Prepared by Plasma Spray

Abstract

Impedance studies of electrolyte supported symmetrical half cells La0,6Sr0,4Co0,2Fe0,8O3- /Ce0,85Y0,15O2-/La0,6Sr0,4Co0,2Fe0,8O3- with electrodes deposited by atmospheric plasma spraying (APS) show that the applied technique influences reversibly the substrate properties, introducing additional contribution to the interface substrate/electrode. After thermal treatment in temperature range 100-800oC during the impedance measurements, an annealing effect is observed. It eliminates the additional increase of the electrolyte resistivity and increases slightly the polarization resistance. The observed effect could be related to thermally and/or mechanically induced local microstructure defects, caused by the APS procedure. The obtained results show that for stabilization of the cell’s performance, annealing should be performed after the APS deposition. It can be supposed that an appropriate annealing atmosphere may prevent the electrodes deactivation