General fabrication of MCo2O4@CeO2 (M = Ni, Cu, Zn, Mn) core@shell nanospheres and their catalytic performances in CO oxidation

A facile strategy is described for general synthesis of MCo2O4@CeO2 (M = Ni, Cu, Zn, Mn) core@shell nanospheres. First, uniform M,Co-glycerate were prepared and served as precursor to produce MCo2O4 spheres by calcination, followed by a reflux process to obtain MCo2O4@CeO2 core@shell spheres. As expected, due to the synergetic effect at the interface between the two components, most of the as-prepared MCo2O4@CeO2 core@shell spheres exhibited enhanced catalytic activities toward CO oxidation compared with the corresponding MCo2O4 spheres and CeO2 nanoparticles.