Synthesis of doped ceria with mesoporous flowerlike morphology and its catalytic performance for CO oxidation

Mesporous flowerlike ceria Ce0.9M0.1O2-delta (M = Y, La, Zr, Pr and Sn) have been synthesized successfully by a hydrothermal method. The impacts of doping on their physical properties are investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen adsorption, Raman and X-ray photoelectron spectroscopy (XPS). The doped materials show relatively high stability against the grain growth at 800 degrees C under reducing and oxidizing atmosphere. The catalytic activities of all flowerlike ceria materials for CO conversion are quite high (200 < T-50 < 320 degrees C) due to their high specific surface area (>100 m(2)/g), open mesoporous structure (pore size similar to 3.9nm) and nano-crystalline nature (grain size < 10 nm). Among flowerlike materials, Pr and Sn doped ceria show enhanced activity while La, Y, Zr doped ceria show decreased activity compared to undoped ceria. (C) 2008 Elsevier Inc. All rights reserved.