Journal ArticleDOI
Characterization of ceria-coated alumina carrier
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In this paper, it was shown that different types of cerium oxide species are formed on the surface depending on the amount of CeO2 and temperature of calcination of the samples.Abstract:
CeO2–Al2O3 mixed oxides with different CeO2 loading (in the range of 0.5–12 wt.%) were prepared by wetness impregnation of alumina with aqueous solution of di-ammonium hexanitrate cerate (NH4)2[Ce(NO3)6]. The samples after calcination at 773 and 1073 K were characterized by different techniques, using X-ray diffraction (XRD), UV–VIS diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS) and temperature-programmed reduction (TPR). It is shown that different types of cerium oxide species are formed on the surface depending on the amount of CeO2 and temperature of calcination of the samples. XRD showed the formation of nanocrystallites of ceria on alumina surface when the amount of CeO2 is higher than 6 wt.%; at lower concentrations ceria was found to be amorphous. The ceria loading lower than 6 wt.% stabilizes the textural properties of alumina. At loading of 1 wt.% of CeO2 XPS spectra reveals the presence of a strong interaction between ceria and alumina leading to a formation of superficial CeAlO3-like phase. TPR results show that well dispersed CeO2 particles present on the surface of alumina form CeAlO3 at temperature of reduction in the range of 873–993 K, while for the reduction of CeO2 crystallites, a higher temperature of reduction of 1190 K is needed.read more
Citations
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Microstructure and mechanical properties of WC–40vol%Al2O3 composites hot pressed with MgO and CeO2 additives
TL;DR: In this paper, the effects of trace amount of MgO and CeO 2 additives on the microstructure and mechanical properties of the WC-40vol%Al 2 O 3 composites prepared by hot pressing were investigated.
Journal ArticleDOI
Improving the dielectric constant of Al2O3 by cerium substitution for high-k MIM applications
Rakesh Sohal,Grzegorz Lupina,Olaf Seifarth,Peter Zaumseil,Christian Walczyk,Thomas Schroeder +5 more
TL;DR: In this article, high-k dielectric cerium-aluminate (Ce 0.7 Al 1.3 O 3 ) thin films were deposited on titanium nitride metal electrodes by electron-beam co-evaporation of ceria and alumina in a molecular beam deposition chamber.
Journal ArticleDOI
Propane dehydrogenation over Al2O3 supported Pt nanoparticles: Effect of cerium addition
TL;DR: In this paper, the influence of promoter cerium (Ce) on the catalyst was investigated by means of transmission electron microscope (TEM), X-ray diffraction (XRD), N2 adsorption-desorption, N2 photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), and H2-temperature programmed reduction (H2-TPR), and catalytic properties for propane dehydrogenation.
Journal ArticleDOI
The Mo modified Ce/TiO2 catalyst for simultaneous Hg0 oxidation and NO reduction
TL;DR: In this article, the combination of molybdenum oxides and cerium oxides exhibits an obvious synergy for Hg0 oxidation and NO reduction and was employed for the first time to simultaneously oxidize elemental mercury (Hg0) and reduce nitrogen monoxide (NO) under simulated SCR atmosphere.
Journal ArticleDOI
Characterization and performance of a ZnO–ZnCr2O4/CeO2–ZrO2 monolithic catalyst for methanol auto-thermal reforming process
TL;DR: In this article, a series of monolithic catalysts of mixed metal oxides (ZnO-ZnCr 2 O 4 / CeO 2 -ZrO 2 ) for methanol auto-thermal reforming (ATR) has been studied.
References
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Journal ArticleDOI
Catalytic Properties of Ceria and CeO2-Containing Materials
TL;DR: A survey of the use of cerium oxide and CeO2-containing materials as oxidation and reduction catalysts is presented in this paper, with a special focus on catalytic interaction with small molecules such as hydrogen, carbon monoxide, oxygen, and nitric oxide.
Journal ArticleDOI
Ceria in automotive exhaust catalysts: I. Oxygen storage
H.C. Yao,Y.F. Yu Yao +1 more
TL;DR: In this article, the authors measured the oxygen removal at various temperatures using TPR traces of unsupported or alumina-supported ceria and showed that the reduction of surface capping oxygen and bulk oxygen anions is associated with reduction of the shared oxygen anion at the interface.
Book
X-Ray Diffraction in Crystals, Imperfect Crystals, and Amorphous Bodies
TL;DR: In the formalism of Newman-Penrose, a family of exact solutions of the Einsteirr-Maxwell equations of the type of Bertotti-Robinson is obtained with a cosmological term belonging to the degenerate type D in the algebraic classification of Petrov.