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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Hydrogen production by aqueous phase reforming of phenol derived from lignin pyrolysis over NiCe/ZSM-5 catalysts
Xiangping Li,Beibei Yan,Jianguang Zhang,Ningge Xu,Junyu Tao,Ruixue Zhang,Bin Liu,Zhixue Sun,Guanyi Chen,Guanyi Chen +9 more
TL;DR: In this paper, NiCe/ZSM-5 catalysts with different ratio of Ni:Ce, and CeO2 was added as an assistant in the synthesis process were characterized by Transmission electron microscopy (TEM), X-ray diffraction (XRD), N2-Sorption, H2 temperature programmed reduction (H2-TPR), Xray photoelectron spectroscopy (XPS), Fourier Transform infrared Spectroscopy(FTIR) and ultraviolet-visible diffuse reflectance spectra (UV-Vis DR).
Journal ArticleDOI
Low temperature catalytic oxidation of NO over different-shaped CeO 2
TL;DR: In this paper, the effect of the morphology of CeO2 nanomaterials on its performance for NO catalytic oxidation was investigated. And the experimental results showed that CeO 2 nanorods are of the best catalytic performance.
Journal ArticleDOI
Activity and hydrothermal stability of CeO 2 –ZrO 2 –WO 3 for the selective catalytic reduction of NO x with NH 3
Zhongxian Song,Ping Ning,Qiulin Zhang,Hao Li,Jinhui Zhang,Yancai Wang,Xin Liu,Zhenzhen Huang +7 more
TL;DR: In this paper, a series of CZW catalysts prepared by a hydrothermal synthesis method showed excellent catalytic activity for selective catalytic reduction (SCR) of NO with NH3 over a wide temperature of 150-550°C.
Journal ArticleDOI
Preparation and Characterization of Spherical Mesoporous CeO2−Al2O3 Composites with High Thermal Stability
TL;DR: In this article, a mixed alumina-ceria hydrosol and hexamethylenetetramine solution were mixed together and added dropwise into a hot oil column where spherical gel particles were formed due to surface tension.
Journal ArticleDOI
Structure and photocatalytic activity studies of TiO2-supported over Ce-modified Al-MCM-41
TL;DR: In this article, a series of Ce modified Al-MCM-41 and TiO{sub 2} loaded composite catalysts are evaluated for photocatalytic degradation of phenol under UV irradiation.
References
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High-Resolution X-Ray Photoemission Spectrum of the Valence Bands of Gold
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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.