The exceptional activity for methane combustion of modular palladium-ceria core-shell subunits on silicon-functionalized alumina that was recently reported has created renewed interest in the potential of core-shell structures as catalysts. Here we report on our use of advanced ex situ and in situ electron microscopy with atomic resolution to show that the modular palladium-ceria core-shell sub...

As the pursuit towards emissions reduction intensifies with growing interest and nascent technologies, solid oxide fuel cells (SOFCs) remain an illustrious candidate for achieving our goals. Despite myriad advantages, SOFCs are still too costly for widespread deployment, even as unprecedented materials developments have recently emerged. This suggests that, in addition to informed materials sel...

The effect of sulfur on the water-gas-shift (WGS) activity of Pd/ceria catalysts has been studied using steadystate rate measurements, pulse-reactor studies, and FTIR. After exposing Pd/ceria to SO2 at 673 K in an oxidizing environment, the WGS rates dropped to a value close to that observed on Pd/alumina. Both pulsereactor and FTIR measurements showed that cerium sulfates can be readily reduce...

Various types of CO sensors based on cerium oxide (ceria) have been reported recently. It has also been reported that the response speed of CO sensors fabricated from porous ceria thick films comprising nanoparticles is extremely high. However, the response value of such sensors is not suitably high. In this study, we investigated methods of improving the response values of CO sensors based on ...

Ceria nanoparticles (NPs) are widely used as fuel catalysts and consequently are likely to enter the environment. Their potential impacts on. biota at environmentally relevant concentrations, including uptake and toxicity, remain to be elucidated and quantitative data on which to assess risk are sparse. Therefore, a definitive assessment of the molecular and phenotypic effects of ceria NPs was ...

The stability of palladium supported on ceria (Pd/CeO2) was studied during liquid flow transfer hydrogenation using primary and secondary alcohols as hydrogen donors. For primary alcohols, the ceria support was reduced to cerium hydroxy carbonate within 14 h and was a contributing factor toward catalyst deactivation. For secondary alcohols, cerium hydroxy carbonate was not observed during the s...

Title of Document: QUANTIFYING THE ROLE OF CERIUM OXIDE AS A CATALYST IN SOLID OXIDE FUEL CELL ANODES Steven C. DeCaluwe, Doctor of Philosophy, 2009 Directed By: Associate Professor Gregory S. Jackson, Department of Mechanical Engineering Solid Oxide Fuel Cells (SOFCs) are an important electrochemical power conversion device, due largely to their high efficiencies and ability to directly oxidiz...

Catalysts based on single atoms of scarce precious metals can lead to more efficient use through enhanced reactivity and selectivity. However, single atoms on catalyst supports can be mobile and aggregate into nanoparticles when heated at elevated temperatures. High temperatures are detrimental to catalyst performance unless these mobile atoms can be trapped. We used ceria powders having simila...

Nickel/doped-ceria composites are promising electrocatalysts for solid-oxide fuel and electrolysis cells. Very often steam is present in the feedstock of the cells, frequently mixed with other gases, such as hydrogen or CO2 . An increase in the steam concentration in the feed mixture is considered accountable for the electrode oxidation and the deactivation of the device. However, direct experi...

Ceria (CeO2) nanorods with well-defined surface planes can be synthesized and utilized for the hydrogenation of nitroaromatics. The CeO2 nanorods containing a {110} plane can efficiently and selectively catalyse the hydrogenation of nitroaromatics with N2H4 as a reducing agent, while nano-ceria with a {100} or {111} plane shows poor performance for the reaction.