Journal ArticleDOI
Characterization of ceria-coated alumina carrier
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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
An investigation into an alternative photocatalyst based on CeO2/Al2O3 in dye degradation
Thaís Martins Neves,Tuanny Santos Frantz,Evelyn Cindy Couto do Schenque,Marcos A. Gelesky,Vanessa Bongalhardo Mortola +4 more
TL;DR: In this article, an alternative catalyst based on CeO2/Al2O3 was evaluated in methylene blue photodegradation. But the results were limited to a single-stage process and only reached 93% degradation.
Journal ArticleDOI
Investigation of the effect of support thermal treatment on gold-based catalysts' activity towards propene total oxidation
TL;DR: In this paper, the effect of support thermal treatment on the activity of gold-based catalysts for the total oxidation of propene Ce 03 Ti 07 O 2 supports were prepared using sol-gel method.
Journal ArticleDOI
Silicotungstic acid modified Ce‐Fe‐Ox catalyst for selective catalytic reduction of NOx with NH3: Effect of the amount of HSiW
Zhongxian Song,Yun Xing,Xuejun Zhang,Heng Zhao,Min Zhao,Jinggang Zhao,Zi’ang Ma,Qiulin Zhang +7 more
Journal ArticleDOI
Effect of Preparation Methods on Al2O3 Supported CuO-CeO2-ZrO2 Catalysts for CO Oxidation
TL;DR: Rattan et al. as discussed by the authors examined the effect of preparation methods, four catalyst samples having same composition (CuCe 5.17 Zr 3.2) were prepared by four different methods for CO oxidation.
Journal ArticleDOI
Synthesis of nanostructured Pt/CeO2–ZrO2–Al2O3 catalysts by a two-step sol–gel method
TL;DR: Porous Pt/CeO2/ZrO2-Al2O3 catalysts were synthesized by a two-step sol-gel method in which noble metal nanoparticles were first prepared as a dispersed colloid in an aqueous medium, then mixed with aluminum isopropoxide (AIP), Ce(NO3)4 and Zr(NO 3)4, and condensed into a gel as discussed by the authors.
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.