Characterization and catalysis studies of CuO/CeO2 model catalysts

CeO2 thin films were prepared via a sol–gel dip-coating process, and used as supports to prepare CuO/CeO2 model catalysts. The catalytic activity of the catalysts for low-temperature CO oxidation was investigated with a micro-reactor-GC system. X-ray diffraction (XRD) patterns indicate that the CeO2 films are of random orientation with dominant (1 1 1) texture, and Cu0.2Ni0.8O phase has formed in CuO/CeO2 model catalysts. The scanning electron microscopy (SEM) and scanning tunneling microscopy (STM) images show the CeO2 film surface is uniform and CuO exists in either cluster or crystal forms. CuO/CeO2/Ni has higher catalytic activity compared to CuO/CeO2/NiO/Ni. The synergistic interaction between CuO and CeO2 is the main factor responsible for high catalytic activity of CuO/CeO2 model catalysts.