中文摘要：

利用X射线衍射（XRD）、拉曼光谱（Raman）、X射线光电子能谱（XPS）和交流阻抗谱对溶胶-凝胶法制备的稀土双掺杂固溶体Ce0.8Gd0.2-xPrxO1.9（x=0,0.02,0.10）的结构和导电性进行了研究.XRD结果表明,经800℃焙烧所得样品都形成了单相立方萤石结构,平均晶粒尺寸在23~30 nm之间;XPS结果表明,样品中Pr离子以混合价态Pr3＋和Pr4＋存在;Raman光谱结果表明,Ce0.8Gd0.2-xPrxO1.9（x=0,0.02,0.10）具有氧缺位的立方萤石结构,Pr离子的掺杂使氧缺位浓度增加;阻抗谱结果表明,稀土双掺杂的固溶体Ce0.8Gd0.2-xPrxO1.9（x=0.02,0.10）的电导率高于稀土单掺杂的固溶体Ce0.8Gd0.2O1.9（σ600℃=1.62×10-3S/cm,Ea=1.12 eV）,其中Ce0.8Gd0.10Pr0.10O1.9的电导率最大（σ600℃=6.15×10-3S/cm）,导电活化能最小[Ea=0.64 eV（〈400℃）,Ea=0.82 eV（〉400℃）],这与样品Ce0.8Gd0.2-xPrxO1.9内部更多的氧离子缺位和小极化子电子导电有关.

英文摘要：

The structure and conductivity of rare earth co-doped ceria Ce0.8Gd0.2 xPrxO1.9（x=0,0.02,0.10） solid solutions synthesized by sol-gel method were characterized by X-ray diffraction,Raman,X-ray photoelectron spectroscopy and impedance spectra.The results of XRD measurement show that all the samples calcined at 800 ℃ crystallize in single cubic fluorite structure.The average grain sizes are between 23 nm and 30 nm.X-ray photoelectron spectroscopy analysis suggest that the mixed valence Pr3＋ and Pr4＋ ions coexist in the solid solutions.The result of Raman spectra show that the solid solution Ce0.8Gd0.2-xPrxO1.9 are cubic fluorite structure with oxygen vacancies.The oxygen vacancy concentration can be increased by doped Pr in Ce0.8Gd0.2-xPrxO1.9.Impedance spectra show that the conductivity of the rare earth co-doped ceria Ce0.8Gd0.2-xPrxO1.9（x=0.02,0.10） is higher than that of single rare earth doped ceria Ce0.8Gd0.2O1.9（σ600 ℃=1.62×10-3 S/cm,Ea=1.12 eV）.Ce0.8Gd0.10Pr0.10O1.9 possessed maximum conductivity of σ600 ℃=6.15×10-3 S/cm and minimum activation energy of Ea=0.64 eV（400 ℃）,Ea=0.82 eV（400 ℃）,which was attributed to higher oxygen vacancy concentratin and the hopping electron transition of small polaron in Ce0.8Gd0.2-xPrxO1.9 samples.