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用溶胶-凝胶法合成了氧化铈稀土双掺杂Ce0.8Nd0.2-xPrxO1.9(x=0,0.10,0.15)固溶体。用X射线衍射(X-ray diffraction,XRD),Raman光谱和交流阻抗谱研究了固溶体的结构和导电性。XRD结果表明:经800℃焙烧所有的样品都形成了单相立方萤石结构,平均晶粒尺寸为22～32nm。X射线光电子能谱结果表明:样品中镨离子以混合价态(Pr3+和Pr4+)存在。Raman谱结果表明:Ce0.8Nd0.2-xPrxO1.9具有氧缺位的立方萤石结构,Pr离子的掺杂有利于氧缺位增加。阻抗谱表明:稀土双掺杂Ce0.8Nd0.2-xPrxO1.9(x=0.10,0.15)的电导率高于稀土单掺样品Ce0.8Nd0.2O1.9的,Ce0.8Nd0.05Pr0.15O1.9的电导率最大,在600℃时的电导率为2.63×10-2S/cm,导电活化能Ea=0.40eV(600～800℃),Ea=0.62eV(400～600℃),与Ce0.8Nd0.05Pr0.15O1.9材料内部更多的氧离子缺位和小极化子电子导电相关。
Cerium rare earth dual doping Ce0.8Nd0.2-xPrxO1.9 (x = 0,0.10,0.15) solid solution was synthesized by sol-gel method. The structure and electrical conductivity of the solid solution were investigated by X-ray diffraction (XRD), Raman spectroscopy and ac impedance spectroscopy. XRD results show that all the samples calcined at 800 ℃ form a single-phase cubic fluorite structure with an average grain size of 22-32 nm. The results of X-ray photoelectron spectroscopy showed that the praseodymium ions exist in the mixed valence state (Pr3 + and Pr4 +). The results of Raman spectroscopy show that Ce0.8Nd0.2-xPrxO1.9 has a cubic fluorite structure with oxygen vacancies. The doping of Pr ions favors the increase of oxygen vacancies. The impedance spectra show that the electrical conductivity of rare earth dual-doped Ce0.8Nd0.2-xPrxO1.9 (x = 0.10,0.15) is higher than Ce0.8Nd0.05Pr0.15O1 which is rare earth doped sample Ce0.8Nd0.2O1.9. 9 had the highest conductivity of 2.63 × 10-2 S / cm at 600 ℃, Ea = 0.40eV (600-800 ℃), Ea = 0.62eV (400-600 ℃) and Ce0. 8Nd0.05Pr0.15O1.9 more oxygen vacancies within the material and small polaron electronic conduction related.