Ce0.8Gd0.2-xPrxO1.9固溶体的合成与表征

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Ce0.8Cd0.2-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;X...

Synthesis and Characterization of Solid Solution Ce0.8Gd0.2-xPrxO1.9

Abstract 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. XRD measurement showed that all powders calcined at 800 ℃ crystallized in single cubic fluorite structure . The average grain sizes were between 23nm and 30 nm. X-ray photoelectron spectroscopy analysis suggested that the mixed valence Pr3+ and Pr4+ ions coexisted in the solid solutions. The Raman spectra analysed that the solid solution Ce0.8Gd0.2–xPrxO1.9 were cubic fluorite structure with the oxygen vacancies.The oxygen vacancy concentration could be increased by doped Pr in Ce0.8Gd0.2–xPrxO1.9. Impedance spectra showed that conductivity of rare earth co-doped ceria Ce0.8Gd0.2–xPrxO1.9 (x=0.02, 0.10) was higher than that of single rare earth doped ceria Ce0.8Gd0.2O1.9(σ600oc =1.62×10–3 S.cm–-1). Ce0.8Gd0.10Pr0.10O1.9 possessed maximum conductivity. At 600℃, the conductivity was 6.15×10–3 S.cm–1 and Ea=0.64eV (<400℃), Ea=0.82eV（>400℃），which was assigned to higher oxygen vacancy concentratin and the hopping electron transition of small polaron in Ce0.8Gd0.2–xPrxO1.9 samples.