Preparation, structure and oxide ion conductivity in Ce6−xYxMoO15−δ (x=0.1–1.4) solid solutions

The Ce6−xYxMoO15−δ solid solution with fluorite-related structure have been characterized by differential thermal analysis/thermogravimetry (DTA/TG), X-ray diffraction (XRD), IR, Raman, scanning electric microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) methods. The electric conductivity of samples is investigated by Ac impedance spectroscopy. An essentially pure oxide-ion conductivity of the oxygen-deficiency was observed in pure argon, oxygen and air. The highest oxygen-ion conductivity was found in Ce5.5Y0.5MoO15−δ ranging from 5.9×10−5 (S cm−1) at 300 °C to 1.3×10−2 (S cm−1) at 650 °C, respectively. The oxide-ion conductivities remained stable over 80 h-long test at 800 °C. These properties suggested that significant oxide-ionic conductivity exists in these materials at moderately elevated temperatures.