MOF-derived CeO2/Au@SiO2 hollow nanotubes and their catalytic activity toward 4-nitrophenol reduction

A novel porous CeO2/Au@SiO2 nanocatalyst with a hollow tube structure was fabricated by using a metal–organic framework as the precursor and sacrificial template. The structure of the nanocatalyst was characterized in detail by TEM, XRD, N2 physical adsorption and XPS. Au nanoparticles with a mean diameter of 4.8 nm were loaded on the Ce-MOF surface because of the strong chemical affinity between Au NPs and carboxylate ions of the Ce-MOF. The pyrolysis of Ce-MOF gave rise to the formation of a mesoporous CeO2 hollow tube without alteration of the Au size due to the encapsulation by a SiO2 shell. The as-prepared CeO2/Au@SiO2 nanocatalyst exhibited excellent catalytic activity towards 4-nitrophenol reduction. The superior catalytic activity was attributed to the unique and small size of the Au nanoparticles, the mesoporous structure and the strong interaction between the CeO2 and Au nanoparticles.