Catalytic oxidation of high-concentration CO over La0.9M0.1CoO3 (M=Ce, Sr) facilely promoted by glucose

The glucose-free and glucose-containing LaCoO3(-G), La0.9Sr0.1CoO3(-G), La0.9Ce0.1CoO3(-G) perovskite catalysts were synthesized via sol-gel method, over which the oxidation performance of high-concentration CO was investigated. The experimental results indicate that the catalytic activity can be improved by facilely adding of glucose during the preparation where glucose creates a reducing atmosphere and takes away the oxygen atoms of perovskites to form more oxygen vacancies and Co3+. The CO self-sustained combustion is favorably achieved and La0.9Ce0.1CoO3-G shows the best catalytic performance. Combined with the XPS, H2-TPR, O2-TPD and CO-TPD results, the outstanding performance of La0.9Ce0.1CoO3-G is mainly ascribed to the relatively higher concentration of Co3+, Ce3+ and oxygen vacancies. The reaction is found to follow the Langmuir-Hinshelwood (L-H) mechanism by in-situ IR and kinetic results. Furthermore, La0.9Ce0.1CoO3-G exhibits good high-temperature durability with unchanged CO conversion of 100% under 760 ˚C. It is suggested that the addition of glucose and the impregnation of Sr or Ce for perovskites is a feasible strategy to design the industrial catalysts for CO self-sustained combustion.