Methane complete and partial oxidation catalyzed by Pt-doped CeO2

We have studied catalytic activity of Pt-doped CeO2 for the oxidation and the dry reforming of methane. The catalyst was prepared by three methods resulting in ceria containing different ratios of ionic Pt versus Pt0. We show that these materials have different catalytic activity for methane oxidation and dry reforming and that they are more active when the fraction of ionic Pt is increased. Density functional theory was used to help understand the role of Pt dopant. It was found that the presence of Pt activates the oxygen atoms next to it in the surface layer and this decreases the activation energy for dissociative adsorption of methane (which is the rate-limiting step in the reaction).

Energy level diagram (calculated) for breaking the C–H bond of methane. Steady state output from the reactor at different temperatures, for methane dry reforming. The catalyst is Pt-doped CeO2.Figure optionsDownload high-quality image (74 K)Download as PowerPoint slide