Effect of the sintering temperature on the properties of Ce0.85La0.10Ca0.05O2-δ electrolyte material

Rare earth and alkaline earth co-doped Ce0.85La0.10Ca0.05O2-δ electrolyte material with the powder obtained by solid-state reaction method was sintered at 1300, 1400, 1500 and 1600 oC respectively. The results showed that the ionic conductivity of the sample sintered at 1400 oC was slightly lower compared to that sintered at 1500 oC in the temperature range of 300-550 oC, while the sample sintered at 1400 oC showed the highest ionic conductivity in all the samples above 550 oC. The ionic conductivity of ∼0.021 S/cm at 600 oC and the relative density of 98.2% were observed for the sample sintered at 1400 oC. In addition, the highest flexural strength with 145 MPa was also obtained for the sample sintered at 1400 oC. It suggested that the sintering temperature for Ce0.85La0.10Ca0.05O2-δ electrolyte may be reduced to as low as 1400 oC with desired properties.