Flash Synthesis and CO Oxidation of Macro-/Nano-porous Co3O4–CeO2 Via Self-Sustained Decomposition of Metal–Organic Complexes

Abstract

Three-dimensional macro/mesoporous Co3O4–CeO2 was prepared via a facile self-sustained decomposition of metal–organic complexes. Porous Co3O4–CeO2 was characterized using X-ray diffraction, scanning electron microscopy/transmission electron microscopy imaging, N2 adsorption/desorption and X-ray photoelectron spectroscopy to examine the morphology and microstructure to find out the cause. Co3O4–CeO2 with the 3D hierarchical porous structure consisting of nanoparticles is a coral-like shape with a size of tens of micrometers and exhibits the hierarchically porous morphology, in which the walls of the macropores contain smaller mesopores. The catalytic performance of the porous Co3O4–CeO2 for CO oxidation has been studied. Among the obtained catalysts, the porous Co3O4–CeO2 with 20 wt% Co exhibits the best catalytic activity and the 50 % CO conversion can be reached at 74 °C. The presence of transition metal element Co can promote the production of oxygen vacancies and improve oxygen mobility, which result in enhancing the oxygen-storage capacity of porous Co3O4–CeO2 and its catalytic performance for CO conversion.