Catalysis Letters, Vol.121, No.1-2, 70-76, 2008
An investigation of catalytic activity for CO oxidation of CuO/Ce-x Zr1-xO2 catalysts
A series of CuO/Ce (x) Zr1-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-Temperature-programmed 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) Zr1-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) Zr1-x O-2 had an effect on the dispersion degree of CuO and the catalytic activity of the catalysts.