Novel SrCe1 − xYbxO3 − α-(Na/K)Cl composite electrolytes for intermediate temperature solid oxide fuel cells.

In this study, novel SrCe 1 − x Yb x O 3 − α (x = 0, 0.05, 0.10, 0.15)-(Na/K)Cl composite electrolytes were synthesized at low temperature (750 °C). The structural and microstructural properties of the composite electrolytes are observed by X–ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that the upper doping limit of Yb 3 + in SrCeO 3 is 15 mol%. The XRD results shown that no chemical reactions take place between SrCe 1 − x Yb x O 3 − α (x = 0, 0.05, 0.10, 0.15) and NaCl/KCl. The SEM images revealed that NaCl/KCl is coated on the surface of SrCe 1 − x Yb x O 3 − α (x = 0, 0.05, 0.10, 0.15) act as a binder. The electrical conductivity is determined by impedance spectroscopy. The log σ ~ log ( p O 2 ) plots results indicate that the composites are almost pure ionic conductors. Finally, the excellent performance of SCYb15-NK is obtained with a maximum power density of 615 mW·cm − 2 at 700 °C. [ABSTRACT FROM AUTHOR]