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
Innovative catalyst design for methane steam reforming intensification
TL;DR: In this paper, the authors focused on the steam reforming (SR) process intensification obtained by deposing the catalyst on a Silicon Carbide (SiC) monolith (porous walls, honeycomb shape), characterized by excellent thermal conductivity and mechanical resistance.
Journal ArticleDOI
Effects of morphology and structure of titanate supports on the performance of ceria in selective catalytic reduction of NO
TL;DR: In this article, the titanates with various morphologies and structures were successfully synthesized in this paper, which were subsequently utilized as supports for CeO2 in selective catalytic reduction of NO.
Journal ArticleDOI
Effect of CeO2 and La2O3 on the Activity of CeO2−La2O3/Al2O3-Supported Pd Catalysts for Steam Reforming of Methane
Wellington H. Cassinelli,L. S. F. Feio,J.C.S. Araújo,Carla E. Hori,Fabio B. Noronha,C.M.P. Marques,José Maria C. Bueno +6 more
TL;DR: In this article, the effect of the addition of CeO2 or La2O3 on the surface properties and catalytic behaviors of Pd catalysts was studied in the steam reforming of methane.
Journal ArticleDOI
Synthesis of CeAlO3/CeO2–Al2O3 for use as a solid oxide fuel cell functional anode material
TL;DR: In this article, a composite electrocatalyst was developed for the purpose of satisfying the features required for use as a solid oxide fuel cell functional anode material, which was the ability to make the direct oxidation of carbon containing fuels in an SOFC without being severely coked.
Journal ArticleDOI
Convenient synthesis of CeO2 nanotubes
TL;DR: In this article, a simple and facile route was used in the fabrication of CeO 2 nanotubes within anodic alumina membrane, which was first immersed into Ce(NO 3 ) 3 aqueous solution under ambient conditions.
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.