CO Oxidation over Au Supported on CexM1-xO2 Mixed Oxides (M=Ti, Zr)

Gold supported on ceria can show high catalytic activity for CO oxidation. CeO2 plays as an oxygen buffer with its strong ability of storing and releasing oxygen. However, CeO2's poor thermal stability makes itself not be a good enough catalytic material. Our job is to prepare CexM1-xO2 (M=Ti, Zr) mixed oxides with various value of x (x=4/5, 2/3, 1/2) to enhance the catalysts' thermal stability by doping M into CeO2. Moreover, research shows that Au/CexM1-xO2 can increase the reactivity of CO oxidation tested by temperature programmed reduction (TPR). Mixed oxides are synthesized by sol-gel method and Au/CexM1-xO2 is prepared by deposition-precipitation (DP) method at PH 7 in this research. X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscope (SEM) are used to characterize the catalysts.