Influence of Fe2O3 addition on the densification and oxygen ion conductivity of the GdSmZr2O7 ceramic

The influence of Fe2O3 addition as a sintering aid on the microstructure and electrical properties of the GdSmZr2O7 ceramic has been studied. The GdSmZr2O7 ceramic with 1 wt.% Fe2O3 is composed of a pyrochlore-type phase and a small amount of Gd0.5Sm0.5FeO3. Fe2O3 is found to be an effective sintering aid for the GdSmZr2O7 ceramic, and a reduction in the sintering temperature of about 200 K is achieved. The total conductivity of the GdSmZr2O7 ceramic incorporated with or without 1 wt.% Fe2O3 obeys the Arrhenius relation. At 1173 K, the highest total conductivity of the GdSmZr2O7 ceramic with 1 wt.% Fe2O3 is about 20% higher than that of the GdSmZr2O7 ceramic. The GdSmZr2O7 ceramic with or without 1 wt.% Fe2O3 is an oxide-ion conductor in the oxygen partial pressure range of 1.0 × 10−4 to 1.0 atm at all test temperature levels.