Successive Interfacial Reaction-Directed Synthesis of CeO2@Au@CeO2-MnO2 Environmental Catalyst with Sandwich Hollow Structure.

Noble metal nanoparticle-based catalysts are widely used for the removal of hazardous materials. During the catalytic reactions, it is of particular importance for developing novel strategies to avoid the leaching or sintering of noble metal nanoparticles. Here, the 4-nitrophenol (4-NP) and CO, typical hazardous chemicals in industrial water and exhaust gases from vehicles, are studied for their removal using CeO2@Au@CeO2-MnO2 catalyst. The sandwich hollow structure is achieved by means of successive interfacial redox reaction without any surfactants and without involving any surface modifications. Because of the synergistic interaction between Au nanoparticles and oxides, the as-prepared environmental catalyst exhibits remarkable activity toward the 4-NP reduction. Moreover, the sandwich structure inhibits the growth of the Au nanoparticles and the as-prepared catalyst still displays high activity toward CO oxidation even when the catalyst is treated at 600 °C.