Facile fabrication of CeO2 hollow microspheres with yeast as bio-templates

CeO2 hollow microspheres were prepared through a facile method by using yeast cells as bio-templates. The yeast provided a solid frame for the deposition of cerium hydroxide to form the hybrid Ce(OH)(3)@ yeast precursor. The resulting CeO2 hollow microspheres were obtained by calcining the precursor. The products were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), fourier transform infrared spectroscopy (FTIR), N-2 adsorption/desorption analysis, X-ray photoelectron spectrum (XPS) and H-2 temperature programmed reduction (H-2-TPR). It was found that the products fully retained the morphology of the yeast cells and the size of the hollow microspheres was about 1.5-2 mu m. The catalytic test results showed that the as-obtained hollow CeO2 microspheres possessed a higher catalytic activity in CO oxidation than the commercial CeO2, which attributed to their higher surface area, hollow structure and superior reducibility. This study provided a promising route for the preparation of a variety of other inorganic hollow microspheres.