Preparation of CeO2/ZnO nanostructured microspheres and their catalytic properties

CeO2/ZnO nanostructured microspheres with an average diameter of about 3.8 μm were synthesized by a solid-stabilized emulsion route. The CeO2/ZnO nanostructured microspheres were characterized with SEM, XRD, CO2-TPD, BET measurement and size analysis. Based on the oxidative coupling reaction of methane with carbon dioxide as an oxidant, the catalytic performance of the CeO2/ZnO nanostructured microspheres was evaluated and compared with that of the CeO2/ZnO nanoparticles. The results showed that the surfaces of the CeO2/ZnO nanostructured microspheres consisted of petal-like structures with a petal thickness of about 90 nm and a petal depth of 0.4 μm to 0.9 μm. Using CeO2/ZnO nanostructured microspheres as catalysts for the oxidative coupling of methane with carbon dioxide, the conversion of methane corresponded with that using the CeO2/ZnO nanoparticles, while the CeO2/ZnO nanostructured microspheres had much longer operating life.