Highly uniform CeO2 hierarchical microstructures: Facile synthesis and catalytic activity evaluation

Highly uniform pancake-like CeOHCO3 hierarchical microstructures have been successfully prepared by a simple gelatin-assisted mixed-solvothermal route. Ceria hierarchical microstructures with similar morphology were obtained after thermal treatment of the CeOHCO3 hierarchical microstructures at 700 °C for 4 h. The CeOHCO3 microstructures can be selectively obtained by varying the composition of solvent, concentration of gelatin and triethylenetetramine (TETA). The as-prepared products were characterized by X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electronic microscope (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM) and selected area electron diffraction (SAED). The possible formation process of the CeOHCO3 microstructures was briefly discussed. Gold coated ceria microstructures were also prepared which show excellent catalytic activity in the conversion of carbon monoxide, the T50 and T90 are at 240 °C and 300 °C, respectively.