کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1331909 | 979022 | 2008 | 9 صفحه PDF | دانلود رایگان |
CeO2 and Ce1−xMxO2−δ (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 Ce4+ in CeO2 by this method. Sizes of crystallites can be tuned by changing the complexing agent and reaction temperature. Nanocrystalline CeO2 and Ce1−xZrxO2 prepared here have higher or at least competitive oxygen storage capacity (OSC) than those reported in literature. Ce1−xFexO2−δ shows higher OSC and higher percentage of CO oxidation at lower temperature than Ce1−xZrxO2.
CeO2 and Ce1−xMxO2−δ (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. Ce1−xFexO2−δ shows higher OSC and higher percentage of CO oxidation at lower temperature than Ce1−xZrxO2. CO conversion with lattice oxygen from (a) CeO2 (5 nm), (b) Ce0.75Zr0.25O2, (c) Ce0.50Zr0.50O2 and (d) Ce0.85Fe0.15O1.85.Figure optionsDownload as PowerPoint slide
Journal: Journal of Solid State Chemistry - Volume 181, Issue 12, December 2008, Pages 3248–3256