Synthesis And Catalytic Properties Of Transition Metal-modified Cerium Oxide-based Materials

Ceria (CeO2) exhibits a nice Redox property and high oxygen storage capacity andthus has wide applications in many important catalytic oxidations. Ceria with differentmorphology and doped cerium-based oxides exposed different crystal surface, increasedconcentration of oxygen vacancies and enhanced oxygen storage/release capacity(OSC).In this paper, we synthesize nanosphere CeO2at180℃for24by hydrothermalmethod. The influence of reaction tempertrus and length of time and surfactants on themorphology and structure were investigated. The materials were characterized by SEM,XRD, H2-TPR, Ramam and UV-Vis and CO oxidation as a probe reaction to investigatecatalytic properties of the relationship between structure and morphology. Thesynthesized CeO2nanosphere show a low crystalline and a large BET surface area(~109m2g-1) and smaller size of particles (25~30nm) and large amount of oxygenvacancies.Therefor they show better catalytic performance on the CO oxidationreaction.We modify the CeO2nanosphere by immersion method, and obtain a series of x%CuO/CeO2catalysts.Using characterization methods such as SEM, XRD, H2-TPR,Raman, UV-Vis the structure of x%CuO/CeO2have been characterized, to explore theeffect of the content of CuO to the carrier, the activity of catalyst was tested used CO asthe probe reaction. The results show that the content of CuO is6%which CO oxidationcatalytic activity of is the best.When the temperature is90℃, the CO conversionreached to100%. Compared with other carrier, with different morphology synthesisedof6%CuO/CeO2, nanosphere CeO2carrier compound6%CuO still has excellent COoxidation catalytic activity.