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A series of CuO/Ce x Zr 1-x O 2 catalyst powders with different Ce/Zr ratio were prepared via an impregnation method and characterized by X-ray diffraction (XRD), Fourier transform Raman (FT-Raman), H 2 -Temperatureprogrammed reduction (TPR) and X-ray photoelectron spectra techniques. The catalytic properties of the catalysts were evaluated by means of a microreactor-GC system. XRD results showed that the addition of CuO had no effect on the crystalline lattice of the support. The structures of the Ce x Zr 1-x O 2 samples were confirmed by XRD analyses and FT-Raman results. The H 2 -TPR profiles for these catalysts had three peaks, which could be attributed to the reduction of three kinds of CuO species, i.e., the highly dispersed CuO, the larger CuO species and the bulk CuO. The TPR analyses and catalytic property tests indicated that the Ce/Zr ratio of CuO/Ce x Zr 1-x O 2 had an effect on the dispersion degree of CuO and the catalytic activity of the catalysts.

Two series of Cu-Ce-O and Cu-Co-Ce-O catalysts were prepared by co-precipitation method. The prepared catalysts were characterized by XRD, IR, TPR, XPS, BET and ICP-AES. The catalytic activities of the catalysts for low-temperature CO oxidation were evaluated through a microreactor-GC system. TPR results indicate that the addition of cobalt to the Cu-Ce-O can increase the dispersion of copper oxide, and the interaction between cobalt and copper can enhance the reducibility of each other. XPS analysis show that Ce 4+ , Cu 2+ , along with Co 3 O 4 , are present on the surface of Cu 0.4 Co 0.6 Ce 4 catalyst. The Co/Cu atomic ratio and the calcination temperature have significant effect on the activities of the catalysts. Compared with Cu 1 Ce 4 catalyst, the Cu 0.4 Co 0.6 Ce 4 catalyst has better activity and thermal stability.

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