Characterization of CeO2-ZrO2 mixed oxides prepared by two different co-precipitation methods

A series of cerium zirconium mixed oxides were prepared by two co-precipitation methods using magnesium hydrogen carbonate (MHC) and mixed ammonia-ammonia hydrogen carbonate (AAHC) as precipitant respectively. The crystal structure, BET surface area and morphology of the produced cerium zirconium mixed oxides were characterized by X-ray diffraction (XRD), Brumauer-Emmett-Teller (BET) and scanning electron microscopy (SEM) techniques. The reduction-oxidation behavior and oxygen storage capacity (OSC) performance were also studied by temperature programmed reduction (TPR) and oxygen pulse chemical adsorption methods. The XRD results demonstrated that the cerium zirconium mixed oxides obtained by both methods possessed structure of cubic solid solution phase. The fresh surface area calcinated at 600 degrees C, aged surface area after 1000 degrees C and OSC at 500 degrees C of cerium zirconium mixed oxides were determined to be 89.337, 34.784 m(2)/g, and 567 mu mol O-2/g for MHC method and 122.010, 46.307 m(2)/g, and 665 mu mol O-2/g for AAHC method, respectively.