Synthesis and characterization of Gd{sup 3+} and Nd{sup 3+} co-doped ceria by using citric acid-nitrate combustion method

Journal Article · Sat Jan 15 00:00:00 EST 2011 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2010.09.035· OSTI ID:22209978

Yao, Hong-Chang ^[1]; Zhang, Yu-Xin ^[1]; Liu, Jia-Jia; Li, Yue-Li; Wang, Jian-She; Li, Zhong-Jun ^[1]

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1. Department of Chemistry, Zhengzhou University, Zhengzhou 450052 (China)

A series of Ce{sub 0.8}Gd{sub 0.2-x}Nd{sub x}O{sub 2-{delta}} (x = 0-0.20) compositions have been synthesized by citric acid-nitrate combustion method. XRD measurements indicate that all the obtained materials crystallized in cubic fluorite-type structure. Lattice parameters were calculated by Rietveld method and the parameter a values in Ce{sub 0.8}Gd{sub 0.2-x}Nd{sub x}O{sub 2-{delta}} system obey Vegard's law, a (A) = 5.4224 + 0.1208x. The obtained powders have good sinterability and the relative density could reach above 95% after being sintered at 1400 {sup o}C. Impedance spectroscopy measurements indicated that the conductivity of Ce{sub 0.8}Gd{sub 0.2-x}Nd{sub x}O{sub 2-{delta}} first increased and then decreased with Nd dopant content x. The maximum conductivity, {sigma}{sub 700{sup o}C} = 6.26 x 10{sup -2} S/cm, was found in Ce{sub 0.8}Gd{sub 0.12}Nd{sub 0.08}O{sub 1.9} when sintered at 1300 {sup o}C. The corresponding activation energies of conduction had a minimum value E{sub a} = 0.676 eV. The results tested experimentally the validity of the effective atomic number concept of recent density functional theory, which had suggested that co-dopant with effective atomic number between 61 (Pm) and 62 (Sm) was the ideal dopant exhibiting high ionic conductivity and low activation energy.

• OSTI ID: 22209978
• Journal Information: Materials Research Bulletin, Vol. 46, Issue 1; Other Information: Copyright (c) 2010 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
ACTIVATION ENERGY
ATOMIC NUMBER
CERIUM OXIDES
CITRIC ACID
COMBUSTION
DENSITY
DENSITY FUNCTIONAL METHOD
DOPED MATERIALS
FLUORITE
GADOLINIUM IONS
IONIC CONDUCTIVITY
LATTICE PARAMETERS
NEODYMIUM IONS
NITRATES
SPECTROSCOPY
SYNTHESIS
VEGARD LAW
X-RAY DIFFRACTION