Anodic behavior of 8Y2O3-ZrO2/NiO cermet using an anode-supported electrode

8Y₂O₃-ZrO₂ (8YSZ)/NiO cermet anode-supported symmetric cell is introduced and fabricated using a tape casting process to analyze the anodic behavior of an anode-supported cell. An anode-supported symmetric cell helps us understand the complex anode structure of cermets. The anodic behavior of 8YSZ/NiO is compared to a MIEC electrode of Sm_0.2Ce_0.8O_1.9 (SDC)/NiO. The anodic behavior of a 8YSZ/NiO cermet electrode is investigated and discussed with respect to the hydrogen partial pressure (p(H₂)), water partial pressure (p(H₂O)), area specific resistance (ASR), activation energy (E_a), thermal cycle, and redox process. Based on these studies, an empirical reaction model of 8YSZ/NiO is established, and the related reaction processes are discussed. On impedance spectra diagram, high and medium frequency arcs are associated with the charge transfer process and the H₂O formation reaction, while the low frequency arc corresponds to the dissociative adsorption and the surface diffusion/gas phase diffusion process. Changes in microstructure by redox and thermal cycling have a significant effect on the electrochemical properties and structural stability of a thick anode-supported cermet structure.