Interfacial reaction phenomenon between La0.25Sr0.75TiO3 and ScSZ

• Interfacial reaction between LST anode and ScSZ in air was confirmed.
• La2Zr2O7 (LZO) was identified to be formed at the interface of LST/ScSZ.
• LZO was effectively suppressed when the sample was annealed in H2 atmosphere.
• The interfacial reaction reduced the performance of the cell with LST anode.

Interfacial reaction phenomenon between stoichiometric La0.25Sr0.75TiO3 (LST) anode and 1CeO2–10Sc2O3–89ZrO2 (ScSZ) electrolyte after annealed at 1200 °C for 30 h in air is investigated. La2Zr2O7 (LZO) phase is found to be formed at the interface of LST/ScSZ via analysis by XRD and SEM measurements. The LZO formation is effectively suppressed when the stoichiometric LST is annealed in reduction atmospheres. The amount of LZO formed at the interface is increased with the annealing time. Based on the experimental results, possible interfacial reaction mechanism between stoichiometric LST and ScSZ electrolyte is proposed.