The oxidation of methane, ethane, propane, and n-butane has been studied over CeO2 and Ce0.8Sm0.2Ox (SDC) catalysts. The rates for methane and ethane were found to be indistinguishable over the two catalysts, while the rates for propane and n-butane were much higher on ceria compared to SDC. The difference between n-butane oxidation over ceria and SDC is shown to result from a low-temperature r...

An FTIR study of CO adsorption from 120 K up to room temperature on a series of Au–ceria samples is presented. Samples with low gold content (0.7 and 0.6 at%) were prepared by urea gelation/co-precipitation and by cyanide leaching of the high-gold content (5.8 at%) material prepared by deposition–precipitation on La-doped CeO2. The samples were subjected to different pretreatments to collect in...

The grain coarsening in dense nanocrystalline gadolinia-doped ceria (CGO) and CeO2 was studied for the grain size regime from 10 to 250 nm. Dense ceria-based thin films were prepared by spray pyrolysis and pulsed laser deposition on sapphire substrates. The small grain-sized CGO and CeO2 microstructures were surprisingly stable and showed self-limited grain growth and relaxation of the microstr...

Reduction of SO, by CO to elemental sulfur on fluorite oxide and transition metal/fluorite oxide composite catalysts is discussed within the redox framework. The oxygen vacancies on the fluorite oxide are active catalyst sites and their creation is a key step to initiate the redox reaction. Transition metal/fluorite oxide composites demonstrate a strong synergism for the reaction. A reduction k...

We investigate the dopant distribution and its influence on the oxygen ion conductivity of ceria doped with rare earth oxides by combining density functional theory and Monte Carlo simulations. We calculate the association energies of dopant pairs, oxygen vacancy pairs and between dopant ions and oxygen vacancies by means of DFT + U including finite size corrections. The cation coordination num...

We present the activities and selectivities of Pt/Al2O3-based catalysts in the production of hydrogen from methanol through catalytic decomposition. For the decomposition reaction, the Pt and Pd catalysts promoted by ceria exhibit similar activity reaching 100% conversion at 315 C. Promoting with ceria had a positive effect on activity and selectivity. Among all catalysts, the 9% Pt– 10% CeO2/A...

Oxygen nonstoichiometry and thermodynamic characterization of Zr doped ceria in the 1573 – 1773 K temperature range

Author(s) of this paper may load this reprint on their own web site provided that this cover page is retained. Republication of this article or its storage in electronic databases or the like is not permitted without prior permission in writing from the IUCr. The results of both a line-broadening study on a ceria sample and a size–strain round robin on diffraction line-broadening methods, which...

pure anatase titania (tio2), mixed 1.0 wt.% cerium-anatase titania (1.0 wt.%ceo2-tio2), and mixed 1.0 wt.% zirconia-anatase titania (1.0 wt.%zro2-tio2) nano powders were synthesized by co-precipitation method and characterized using x-ray diffraction (xrd), brunauer-emmett-teller (bet) surface area analysis, uv-vis diffuse reflectance spectroscopy (drs), and transmission electron microscope (te...

In the finishing process of optical glass, polishing with ceria, silica or zirconia slurry is conventionally adopted. The machining process, however, has problems involving inefficiency and a detrimental impact on the environment. Therefore, it is strongly recommended that the process be replaced with fixed-abrasive machining, but conventional fixed-abrasive tools have problems relating to low ...