Design and Fabrication of Solid Electrolyte for the Prevention of Electrode/Electrolyte Delamination

Abstract

The stability of a solid oxide cell is strongly dependent on the magnitude and profile of internal chemical potential of solid electrolyte. If internal partial pressure is abnormally high, the electrolyte can be delaminated from the electrodes. The formation of high internal pressure is attributed to very low electronic conduction in solid electrolyte. This phenomenon can be significant when the cell is subjected to abnormal operation conditions such as a negative cell voltage. Herein, we suggest a new design of single layer solid electrolyte having local electronic conduction for the prevention of electrode/electrolyte delamination. YSZ and (NiO + YSZ + CeO2) were prepared as electrolyte and anode functional layer, respectively, and these layers were co-sintered at a high temperature, leading to diffusion of cerium ion into YSZ electrolyte. EDS analysis revealed that electronic conduction was locally developed at the anode/electrolyte interface region. The cells were tested under a negative voltage condition using potentiostat. The results indicate that the addition of electronic conduction in the electrolyte can effectively depress internal pressure and prevent anode/electrolyte delamination.