Review on local structural properties of ceria-based electrolytes for IT-SOFC

In general, many attempts have been focused on enhancement of oxy-ion conductivity at intermediate temperature range in order to have a feasible operating temperature of solid oxide fuel cell (SOFC). Every effort is directed towards the creation of defect-rich structure so as to get either ion or vacancy movement, which, in turn, offers more ionic conductivity. Doping is one of the strategies where isovalent, aliovalent, codopant, and multidopant are the sources to create defects. Doped ceria electrolytes have shown potential to reduce the operating temperature of SOFCs at an intermediate temperature (350–550 °C) range due to high ionic conductivity at comparatively low temperature. In the present work, a local structure of nano-sized aliovalent Ce0.85(M)0.15O2–8 and codoped ceria systems Ce0.85(Sm)0.075(M)0.075O2 − δ (where M = Sm, Sr, Gd, Nd, Ca, and Dy) prepared by a hydrothermal synthesis route followed by characterization with extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) is reviewed.