Preparation of Ce1-x Fe x O2 solid solution and its catalytic performance for oxidation of CH4 and CO

A series of Ce1-x Fe (x) O-2 (0 < x <= sign 0.5) catalysts were prepared by the co-precipitation method, and their catalytic performances were investigated for the total oxidation of CO and CH4 as model reactions. X-ray diffraction (XRD) and Raman spectroscopy results show that Ce1-x Fe (x) O2-delta solid solutions are formed with x <= 0.2. Ce0.9Fe0.1O2 solid solution presents superior catalytic performance for CH4 and CO oxidation, while Ce1-x Fe (x) O-2 with x > 0.2 shows less active for CO and CH4 oxidation. The results of H-2-temperature programmed reduction (H-2-TPR), CH4-temperature programmed surface reaction (CH4-TPSR) and CO-TPSR reveal that, the surface oxygen of catalyst is relevant to CO oxidation, which was promoted by the oxygen vacancies formed in Ce-Fe-O solid solution, while the easier lattice oxygen migration property and the favorable reducibility of the catalysts is responsible for the promoted catalytic performance for CH4 oxidation.