Journal ArticleDOI
Characterization of ceria-coated alumina carrier
TLDR
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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Journal ArticleDOI
α-Alumina supported doped ceria catalysts for steam gasification and oxidation of radical coke
Shilpa Mahamulkar,Kehua Yin,Taylor P. Sulmonetti,Hyuk Taek Kwon,Robert J. Davis,Liwei Li,Hirokazu Shibata,Andrzej Malek,Christopher W. Jones,Pradeep K. Agrawal +9 more
TL;DR: A series of α-alumina supported doped (Mn, Gd, Sr) ceria catalysts was investigated for the gasification (steam) and oxidation (air) of industrial coke that was generated during ethane pyrolysis as discussed by the authors.
Journal ArticleDOI
Performance of Mo12Bi1.0Co4.4Fe1.0K0.07Ox catalysts prepared from a sol–gel solution containing added ethylene glycol in the partial oxidation of propylene to acrylic acid
TL;DR: In this article, the performance of mixed metal-oxide catalysts, which were prepared from a sol-gel solution containing different amounts of pre-added ethylene glycol (EG), in the partial oxidation of propylene was investigated.
Journal ArticleDOI
Amorphous (CeO2)0.67(Al2O3)0.33 high-k gate dielectric thin films on silicon
TL;DR: In this article, the electrical and physical properties of (CeO2)0.67(Al2O3) 0.33 (CAO) for use in metaloxide-semiconductor gate dielectric applications were investigated.
Journal ArticleDOI
Oxidative Steam Reforming of Bioethanol over Rh/CeO2-Al2O3 Catalyst for Hydrogen Production
Anamika Srivastava,Kamal K. Pant +1 more
TL;DR: In this paper, the effects of temperature (450°C and 550°C), Water/Ethanol ratio (mol/mol) (3 and 8), and Oxygen/ethanol molar ratio (0.23 and 0.3) were studied at 1 atmospheric pressure in a down-flow tubular fixed bed reactor.
Journal ArticleDOI
Synthesis and radiation tolerance of Lu 2-x Ce x Ti 2 O 7 pyrochlores
TL;DR: In this article, a series of Lu 2− x Ce x Ti 2 O 7 ( x ǫ = 0, 0.5, 1) samples were synthesized to study the solubility and radiation tolerance in pyrochlore matrixes.
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.