Well-defined ceria nanocubes covered by oleic acid with exposed {100} facets have been synthesized and exhibited exclusive selectivity for the oxidation of toluene to benzaldehydes in liquid phase by O(2).

Cerium oxide (ceria) plays an important and fascinating role in heterogeneous catalysis as illustrated by its versatile use a catalyst, catalyst support, or promotor various oxidation reduction reactions. Central to these reactions is the rich defect chemistry, facile redox capability, unusual acid-base properties of ceria. Understanding unique ceria essential build structure-catalysis relation...

Surface reduction of ceria nano octahedra with predominant {111} and {100} type surfaces is studied using a combination of aberration-corrected Transmission Electron Microscopy (TEM) and spatially resolved electron energy-loss spectroscopy (EELS) at high energy resolution and atomic spatial resolution. The valency of cerium ions at the surface of the nanoparticles is mapped using the fine struc...

The kinetics of CO2 reduction over nonstoichimetric ceria, CeO2-δ, a material of high potential for thermochemical conversion of sunlight to fuel, has been investigated for a wide range of nonstoichiometries (0.02 ≤ δ ≤ 0.25), temperatures (693 ≤ T ≤ 1273 K), and CO2 concentrations (0.005 ≤ pCO2 ≤ 0.4 atm). Samples were reduced thermally at 1773 K to probe low nonstoichiometries (δ < 0.05) and ...

The efficient electro-reduction of CO2 to chemical fuels and the electro-oxidation of hydrocarbons for generating electricity are critical toward a carbon-neutral energy cycle. The simplest reactions involving carbon species in solid-oxide fuel cells and electrolyzer cells are CO oxidation and CO2 reduction, respectively. In catalyzing these reactions, doped ceria exhibits a mixed valence of Ce...

ABSTRACT Infrared spectroscopy has been employed for a detailed characterization of ZrO2 and CeO2/ZrO2 supported nickel and copper/nickel catalysts to be utilized for methane decomposition. Adsorption of CO at 303 K was performed in order to determine the surface composition and accessible adsorption sites. Alloy formation occurred during reduction, as indicated by a red-shift of the vibrationa...

Fuel cells, and in particular solid-oxide fuel cells (SOFCs), enable high-efficiency conversion of chemical fuels into useful electrical energy and, as such, are expected to play a major role in a sustainable-energy future. A key step in the fuel-cell energy-conversion process is the electro-oxidation of the fuel at the anode. There has been increasing evidence in recent years that the presence...

The partial oxidation of methane to syngas was studied in this work over Ni-containing ceria catalysts with nickel content of 5, 10 and 20 at.% at atmospheric pressure. All catalysts, in the as prepared state, showed similar activity and CO selectivity at T ≥ 550◦C. Catalyst pre-reduction was not required. Reaction mixtures were dilute, containing 3 mol% CH4 and 1.5 mol% O2. Methane conversion ...

in this work, ce0.75gd0.1ca0.15o1.8 nanopowders are successfully synthesized by a glycine-nitrate combustionprocess under the microwave irradiation. then calcination was carried out at 700 °c. calcined powdersidentified by room temperature x-ray diffraction were single phase and had a crystallite size between 16 to 24nm (based on schererr formula). scanning electron microscopy (sem) was employe...

The water–gas shift (WGS) reaction (CO+H2OQCO2+H2) plays an important role in fuel processing for polymer electrolyte membrane (PEM) fuel-cell applications. The hydrogen in the reformate gas is upgraded by removal of the carbon monoxide, which is a strong poison of the anode catalysts in current PEM fuel cells. Active shift catalysts that are also stable under the operating conditions of practi...