Electrical conductivity and stability of Gd-doped ceria/Y-doped zirconia ceramics and thin films

The interaction between Ce0.90Gd0.10O1.95 (CGO) and Y0.16Zr0.84O1.92 (YSZ) and the electrical conductivity and thermal expansion for solid solutions of CGO and YSZ have been studied. Thin films of CGO interacted with YSZ substrates around 1000 °C, with diffusion of Zr into CGO. The reaction between CGO and YSZ powder started around 1200 °C. The diffusion of Ce into YSZ was the main reaction. The solid solutions of CGOx–YSZ1−x were single phase and possessed a lower conductivity than that of either CGO or YSZ. The electrical conductivity for the solid solutions increased with decreasing oxygen activity, whereas the pO2 independent ionic conductivity region was not observed. The dimensional expansion due to reduction (chemical expansion) was larger for the solid solutions compared to that for of CGO and YSZ.