Synthesis and Characterization of Fe-Doped CeO2 for Application in the NO Selective Catalytic Reduction by CO

We prepared Ce1-xFexO2-delta mixed oxides (x = 0; 0.05; 0.1; 0.15 and 0.2) by Pechini method and we characterized the materials by X-ray fluorescence, X-ray diffraction, N-2 physisorption, UV-Vis diffuse reflectance spectroscopy and scanning electron microscopy. The mixed oxides were evaluated in the selective catalytic reduction of NO by CO. The characterization showed that the synthesis method is suitable for obtaining oxides with desired stoichiometry and single phase solid solution for all Fe contents. The catalytic tests allowed to conclude that Ce1-xFexO2-delta are promising for NO abatement by CO due to the improvement of the physicochemical properties of the synthesized solid solutions by Fe incorporation, such as decreasing crystallite sizes and increasing oxygen vacancies. Ce1-xFexO2-delta mixed oxides were able to dissociate NO even at room temperature due to the presence of the anionic vacancies. The increase of iron content in the mixed oxides enhanced the catalytic activity and selectivity to N-2.