Ceria–Yttria‐Stabilized Zirconia Composite Ceramic Systems for Applications as Low‐Temperature Electrolytes

Ceramic samples of Ce 1− x Gd x O 2− y and yttria‐stabilized zirconia (YSZ) were prepared using solid‐state methods. Polished faces of disks of these materials were held in intimate contact in a reaction cell at temperatures ranging from 1000° to 1300°C for durations up to 72 h. XRD, SEM, and microprobe Raman techniques were used to analyze the resulting reactions and ion diffusion. No reaction was observed at 1000°C after 72 h between the 10‐mol%‐ and 20‐mol%‐Gd‐doped CeO 2 and the YSZ. However, at 1300°C, a mixing region 25 μ m wide occurred, resulting in a cubic phase, where Zr 4+ ions diffused into the CeO 2 .