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

Abstract

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), N2 adsorption/desorption analysis, X-ray photoelectron spectrum (XPS) and H2 temperature programmed reduction (H2-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 μm. 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.