Microstructures and electrolytic properties of yttrium-doped ceria electrolytes: Dopant concentration and grain size dependences

The microstructures and electrolytic properties of YxCe1−xO2−x/2 (x = 0.10–0.25) electrolytes with average grain size in the range 90 nm–1.7 μm were systematically investigated. Through detailed transmission electron microscopy characterization, nanosized domains were observed. The relationship of the domains, the doping level and grain sizes were determined, and their impacts on the electrolytic properties were systematically studied. It was found that the formation of domains has a negative impact on the electrolytic properties, so that electrolytic properties can be adjusted through careful control of domain formation, doping level and grain size.