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Co_3O_4/CeO_2 composites with high surface areas and ultrafine crystalline sizes for catalytic combustion of methane were firstly prepared by a new sol-gel method which combined ultrasonic impregnation treatment and calcination in N_2 atmosphere. The samples were characterized by various means such as nitrogen adsorption/desorption, X-ray diffraction(XRD), H_2 temperature-programmed reduction(H_2-TPR),X-ray photoelectron spectroscopy(XPS) and transmission electron microscopy(TEM). Results showed that the modified catalyst had the mesoporous structure, comparatively higher amount of surface oxygen and larger oxygen vacancies than others. As a result of the structure and surface composition merits, a high methane combustion conversion(50%) could be obtained at a low temperature of 262 °C for the modified Co_3O_4/CeO_2 composites catalysts. The experimental results demonstrated that ultrasonic impregnation treatment combined with the N_2 thermal treatment prior to calcination in air had a promising application for preparation of Co_3O_4/CeO_2 composites catalysts for low-temperature catalytic combustion of methane.
Co_3O_4 / CeO_2 composites with high surface areas and ultrafine crystalline sizes for catalytic combustion of methane were pre- prepared by a new sol-gel method which combined ultrasonic impregnation treatment and calcination in N_2 atmosphere. The samples were characterized by various means such as nitrogen adsorption / desorption, X-ray diffraction (XRD), H_2 temperature-programmed reduction (H_2-TPR), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) amount of surface oxygen and larger oxygen vacancies than others. As a result of the structure and surface composition merits, a high methane combustion conversion (50%) could be obtained at a low temperature of 262 ° C for the modified Co_3O_4 / CeO_2 composites catalysts . The experimental results of that ultrasonic impregnation treatment combined with the N_2 thermal treatment prior to calcination in air had a promising application for preparation of Co_3O_4 / CeO_2 composites catalysts for low-temperature catalytic combustion of methane.