Interdiffusion at electrochemical interfaces between yttria-stabilized zirconia and doped ceria

• Published in: Journal of the European Ceramic Society Vol. 43; no. 14; pp. 6189 - 6199
• Main Authors: Schwiers, Alexander, Lenser, Christian, Guillon, Olivier, Menzler, Norbert H.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2023
• Subjects: Doped ceria; Electrochemistry; Fuel cell materials; Interdiffusion; Interfaces; Interfaces; Electrochemistry; Fuel cell materials; Interdiffusion; Doped ceria
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/j.jeurceramsoc.2023.06.015

Integration of doped ceria into fuel electrode-supported solid oxide cells is challenging due to high sintering temperatures leading to undesirable interdiffusion between the layers. We investigate the influence of the dopant in ceria X0.1Ce0.9O1.95 (10XDC, X = Y, Gd or Sm) on the interdiffusion with yttria-stabilized zirconia (8YSZ). Powder mixtures of 8YSZ and 10XDC were sintered at temperatures between 1000 and 1400 °C to quantify the phase formation. Interdiffusion in layered systems sintered at 1400 °C was investigated by SEM. Symmetrical Ni-10XDC cells with an 8YSZ electrolyte were analyzed using impedance spectroscopy. Despite small differences in the interdiffusion behavior, different dopants do not lead to significant changes in the cell impedance. Notably, the presence of NiO in the fuel electrode leads to enhanced interdiffusion kinetics of 10XDC with 8YSZ and the formation of porosity at the electrolyte interface. The detrimental influence of these microstructural changes on the electrode performance was investigated. [Display omitted] •Dopants in ceria modify the interdiffusion kinetics with yttria-stabilized zirconia.•The presence of NiO during sintering leads to porosity at the ceria/zirconia interface.•Porosity results in drastic loss of fuel electrode performance.•Porosity at the electrolyte interface can be prevented by adding an interlayer.