Nanocast Ordered Mesoporous CeO2 as Support for Highly Active Gold Catalyst in CO Oxidation

Ordered mesoporous ceria oxides (CeO2) were synthesized by nanocasting using ordered mesoporous carbon (CMK-3) as the template and cerium nitrate as the CeO2 precursor. The as-prepared materials were characterized by thermogravimetry, elemental analysis, powder X-ray diffraction, transmission electron microscopy, and N2 adsorption. The obtained ceria exhibits a 2-D hexagonal ordered structure with a high surface area of up to 167 m2/g and pore size in the range of 3–5 nm. The carbon template can be completely removed at a temperature as low as 350°C. Such ceria was then employed as the support for the preparation of gold catalysts by the colloid deposition method. The catalytic activity of the Au/CeO2 catalyst was evaluated in CO oxidation. An enhanced catalytic activity was observed over such a catalyst possibly due to the nano-sized particle and narrow pore size of the ordered mesoporous ceria.