CeO2 nanorods and gold nanocrystals supported on CeO2 nanorods as catalyst

The formation mechanism of uniform CeO(2) structure at the nanometer scale via a wet-chemical reaction is of great interest in fundamental study as well as a variety of applications. In this work, large-scale well-crystallized CeO(2) nanorods with uniform diameters in the range of 20-30 nm and lengths up to tens of micrometers are first synthesized through a hydrothermal synthetic route in 5 M KOH solution at 180 degrees C for 45 h without any templates and surfactants. The nanorod formation involves dehydration of CeO(2) nanoparticles and orientation growth along the (110) direction in KOH solution. Subsequently, gold nanoparticles with crystallite sizes between 10 and 20 nm are loaded on the surface of CeO(2) nanorods using HAuCl(4) solution as the gold source and NaBH(4) solution as a reducing agent. The synthesized Au/CeO(2) nanorods demonstrate a higher catalytic activity in CO oxidation than the pure CeO(2) nanorods.