Controlled synthesis of nanocrystalline CeO{sub 2} and Ce{sub 1-x}M{sub x}O{sub 2-{delta}} (M=Zr, Y, Ti, Pr and Fe) solid solutions by the hydrothermal method: Structure and oxygen storage capacity

Journal Article · Mon Dec 15 04:00:00 EST 2008 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2008.08.018· OSTI ID:21212129

Singh, Preetam ^[1]

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1. Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 (India)

CeO{sub 2} and Ce{sub 1-x}M{sub x}O{sub 2-{delta}} (M=Zr, Ti, Pr, Y and Fe) nanocrystallites of 5-10 nm sizes have been synthesized by hydrothermal method using diethylenetriamine (DETA) and melamine as complexing agents. Compounds have been characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray analysis (EDX) and their structures have been refined by the Rietveld method. All the compounds crystallize in cubic fluorite structure. Even up to 50% Zr and Y, 40% Ti, 25% Pr and 15% Fe is substituted for Ce{sup 4+} in CeO{sub 2} by this method. Sizes of crystallites can be tuned by changing the complexing agent and reaction temperature. Nanocrystalline CeO{sub 2} and Ce{sub 1-x}Zr{sub x}O{sub 2} prepared here have higher or at least competitive oxygen storage capacity (OSC) than those reported in literature. Ce{sub 1-x}Fe{sub x}O{sub 2-{delta}} shows higher OSC and higher percentage of CO oxidation at lower temperature than Ce{sub 1-x}Zr{sub x}O{sub 2}. - Graphical abstract: CeO{sub 2} and Ce{sub 1-x}M{sub x}O{sub 2-{delta}} (M=Zr, Ti, Pr, Y and Fe) nanocrystallites of 5-10 nm sizes have been synthesized by hydrothermal method using diethylenetriamine (DETA) and melamine as complexing agents. Ce{sub 1-x}Fe{sub x}O{sub 2-{delta}} shows higher OSC and higher percentage of CO oxidation at lower temperature than Ce{sub 1-x}Zr{sub x}O{sub 2}. CO conversion with lattice oxygen from (a) CeO{sub 2} (5 nm), (b) Ce{sub 0.75}Zr{sub 0.25}O{sub 2}, (c) Ce{sub 0.50}Zr{sub 0.50}O{sub 2} and (d) Ce{sub 0.85}Fe{sub 0.15}O{sub 1.85}.

• OSTI ID: 21212129
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 12 Vol. 181; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CERIUM IONS
CERIUM OXIDES
CHELATING AGENTS
HYDROTHERMAL SYNTHESIS
IRON COMPOUNDS
NANOSTRUCTURES
OXIDATION
OXYGEN
PRASEODYMIUM COMPOUNDS
SOLID SOLUTIONS
TITANIUM COMPOUNDS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
X-RAY PHOTOELECTRON SPECTROSCOPY
YTTRIUM COMPOUNDS
ZIRCONIUM COMPOUNDS