The effect of support morphology and impregnation medium on the activity of Cu/CeO 2 catalysts in the water gas shift reaction was investigated. Steady-state reaction experiments showed that the catalysts supported over CeO 2 nanoparticles achieved significantly higher CO conversions than catalysts supported over nanorods, which achieved only marginally higher conversions than the bare support. The catalysts were characterized by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, N 2 O chemisorption, and H 2 -temperature-programmed reduction. Characterization of the catalysts showed that copper dispersion and catalytic activity were strongly correlated. Copper was observed to be better dispersed over CeO 2 nanoparticles, whereas larger, crystalline CuO domains with properties closer to that of bulk CuO were identified over CeO 2 nanorods. The finely dispersed copper species constitute the active sites for the WGS reaction over Cu/CeO 2 catalysts.

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Nitrogen containing nano-structured carbon catalysts were grown on Fe/Al 2 O 3 and Ni/Al 2 O 3 supports using acetonitrile pyrolysis. The post-pyrolysis samples were tested for activity in the oxygen reduction reaction (ORR) and oxidative dehydrogenation (ODH) reaction. Samples were characterized using BET, XPS and TEM. The samples grown over iron containing supports gave the highest activity in both reactions. There was a strong correlation between ODH and ORR activity suggesting the possibility of a common active site between reactions with the quinone/hydroquinone group being a possible candidate. XPS analysis supported this hypothesis showing that catalysts with a higher percentage of oxygen in the form of quinones tend to have the highest ORR and ODH activity. XPS analysis also demonstrated that samples with higher pyridinic nitrogen content, which is a marker for edge plane exposure and may be a part of the ORR active site, gave higher ORR and ODH activity. TEM images confirm that samples with high pyridinic nitrogen content tend to form structures with higher edge plane exposure. Because the active site, regardless of its identity, likely lies on the graphitic edge plane, this leaves the possibility that a common active site is not necessary to explain the correlation between ODH and ORR activity.

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