Self-template hydrothermal synthesis of CeO2 hollow nanospheres

CeO2 hollow nanospheres were synthesized by a low-cost and environmentally benign one-pot hydrothermal route. Templates, surfactants, or other auxiliaries were not used in the route. X-ray diffraction, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and nitrogen adsorption-desorption measurements were used to characterize the products. The average diameter of hollow spheres, with shells of approximately 30 nm, was about 300 nm. The formation of these hollow spheres involved a transformation from Ce(OH)CO3 solid spheres to CeO2 hollow nanospheres. The CeO2 hollow nanospheres exhibited a higher catalytic activity on CO oxidation than CeO2 nano-octahedrons.