Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (11): 2451-2458.doi: 10.3866/PKU.WHXB201309041

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Preparation of NiO/CeO2 Catalysts by Solid State Impregnation and Their Application in CO Oxidation

SUN Jing-Fang1, GE Cheng-Yan1, YAO Xiao-Jiang1, CAO Yuan1, ZHANG Lei1, TANG Chang-Jin1, DONG Lin1,2   

  1. 1 Key Laboratory of Mesoscopic Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, P. R. China;
    2 Jiangsu Key Laboratory of Vehicle Emissions Control, Center of Modern Analysis, Nanjing University, Nanjing 210093, P. R. China
  • Received:2013-05-13 Revised:2013-09-04 Published:2013-10-30
  • Contact: TANG Chang-Jin, DONG Lin E-mail:tangcj@nju.edu.cn;donglin@nju.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21273110), Jiangsu Province Science and Technology Support Program, China (Industrial, BE2011167), and Opening Project Program of the State Key Laboratory of Physical Chemistry of Solid Surfaces (Xiamen University), China (201207).

Abstract:

NiO/CeO2 catalysts with different NiO loadings were prepared by a novel solid state impregnation method. The physical and chemical properties of these catalysts were compared with those of catalysts prepared by traditional wet impregnation method. The catalysts were tested for low temperature catalytic CO oxidation and characterized by X-ray diffraction (XRD), N2 physical adsorption, transmission electron microscopy (TEM), H2 temperature-programmed reduction (H2-TPR), Raman spectrum, and X-ray photoelectron spectroscopy (XPS). CO oxidation results showed that nickel-ceria catalysts were good candidates for low temperature CO oxidation, with complete oxidation achieved at temperatures below 200 ℃. The activity of the catalysts increased with nickel loading, and those prepared using the solid state impregnation method displayed higher activities than those prepared by wet impregnation method at the same nickel loading. TEM, XPS, and H2-TPRresults showed that solid state impregnation increased the dispersion of the nickel species on the surface of catalysts and strengthened the interactions between nickel and cerium, which benefited the reduction of nickel species. Raman results showed that the 0001 concentration of oxygen vacancies in the catalysts could be increased using the solid state impregnation method, likely because of more doped nickel ions in the ceria lattice, which promote the activation of oxygen molecules to facilitate the CO oxidation.

Key words: NiO/CeO2, CO oxidation, Solid state impregnation, Wet impregnation, Interfacial interaction