Preparation and characterization of Cu-doped mesoporous CeO₂ for CO oxidation

Abstract

Mesoporous CeO₂ was first synthesized by hydrothermal method, and then used to synthesize different contents of CuO)_x/CeO₂ (x: molar ratio of Cu to Ce) by deposition-precipitation method. These materials were characterized by X-ray diffraction (XRD), N₂ adsorption and desorption, H₂ temperature programmed reduction (H₂-TPR) and O₂ temperature programmed desorption (O₂-TPD) to study the crystal structure, surface area, and the mechanism of CO oxidation. The results show that, on XRD patterns, no evidence of CuO diffraction peaks is present until Cu loading is increased to 20%. The BET surface area decreases noticeably with the increase of Cu content. Compared with other samples, the better reducibility and activity oxygen species of (CuO)_10%/CeO₂ coincide with its better catalytic activity.

Keywords

mesoporous CeO₂ / catalytic activity / CuO/CeO₂ / CO oxidation

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