Hierarchical Structure and Catalytic Activity of Flower-Like CeO2 Spheres Prepared Via a Hydrothermal Method

Hierarchical CeO₂ particles were synthesized by a hydrothermal method based on the reaction between CeCl₃·7H₂O and PVP at 270 °C. The flower-like CeO₂ with an average diameter of about 1 μm is composed of compact nanosheets with thicknesses of about 15 nm and have a surface area of 36.8 m²/g, a large pore volume of 0.109 cm³/g, and a narrow pore size distribution (14.9 nm in diameter). The possible formation mechanism of the hierarchical CeO₂ nanoparticles has been illustrated. The 3D hierarchical structured CeO₂ exhibited a higher catalytic activity toward CO oxidation compared with commercial CeO₂.