Insights into the redox properties of ceria-based oxides and their implications in catalysis

In the present work, the redox properties of ceria and related materials will be considered with a focus on these effects that are relevant in catalysis. Particularly, after briefly pointing out the relevant redox chemistry and characterization of ceria in classical TWC application, we will describe how the reduction/oxidation characteristics of ceria are of help in other applications, like the development of advanced ceria-zirconia based catalyst for auto exhaust treatment, and the elimination of soot from diesel engine exhaust. In the first example, different catalyst formulations based on ceria and zirconia are examined to see how catalytic activity is related with composition and a simple redox mechanism model for CO oxidation is also derived. A similar approach is used to characterize the role of ceria in the combustion of soot. (c) 2005 Elsevier B.V. All rights reserved.