Synthesis and Electrical Properties of New Solid State Electrolyte Materials Ce_(6-x)Sm_(x)MoO_(15-δ)(0≤x≤1.2)

A new solid electrolyte series of oxides Ce_(6-x)Sm_(x)MoO_(15-δ)(0≤x≤1.2) were synthesized by sol-gel method.The precursors and the resultant oxide powders were characterized by differential thermal analysis/thermogravimetry(DTA/TG),X-ray Diffraction(XRD) and X-ray Photoelectron Spectroscopy(XPS).The formation temperature of the compounds was found to be as low as 400 ℃.Ce_(6-x)Sm_(x)MoO_(15-δ) crystallized to fluorite-related cubic structure.The electrical conductivity of samples was investigated by using AC impedance spectroscopy.Impedance spectra analyses show that the grain-boundary resistance of the solid electrolyte prepared by sol-gel method wad reduced or even eliminated.It shows that the presence of Sm is related with the oxygen-ion conductivity.The highest oxygen-ion conductivity is found in Ce_(6-x)Sm_(x)MoO_(15-δ)(x=0.8) reaching 6.67×10~(-3) S/cm at 800 ℃. The Ce_(6-x)Sm_(x)MoO_(15-δ)ionic conductor shows a potential application in the intermediate-temperature solid oxide fuel cells(SOFCs).