Investigation of the crystal structure and ionic conductivity in the ternary system (Yb2O3)x–(Sc2O3)(0.11−x)–(ZrO2)0.89 (x = 0–0.11)

The ternary system (Yb2O3)x–(Sc2O3)(0.11−x)–(ZrO2)0.89 (x = 0–0.11) specimens have been prepared using a co-precipitation method. The properties of this series of samples are affected by the ytterbium element. A stabilized cubic phase is obtained at room temperature by introducing ytterbium and the unit cell parameters show a linear increasing relationship with content of Yb2O3, which also contributes to abatement of the conductivity from 0.099 S/cm to 0.020 S/cm at 800 °C. However, the conductivity tends to remain a constant at lower temperatures ranging from 500 °C to 650 °C as the addition of Yb2O3 is reduced to below 3 mol%, achieving high up to 0.015 S/cm at 650 °C for a 3Yb8ScSZ body, indicating a potential to be utilized as an electrolyte material for intermediate temperature solid oxide fuel cells.

► We investigated the ternary system (Yb2O3)x–(Sc2O3)(0.11−x)–(ZrO2)0.89 (x = 0–0.11) as electrolytes for solid oxide fuel cells.
► Increasing content of Yb2O3 increased the unit cell parameters linearly and stabilized the cubic phase to room temperature.
► Increasing content of Yb2O3 decreased the conductivity at 800 °C while increased below 650 °C.
► The (Yb2O3)0.03–(Sc2O3)0.08–(ZrO2)0.89 sample have potential to be used in low temperature region.