Growth Of CeO2 Research Articles

Influence of the preparation method on the characteristics of TiO2-CeO2 supports

The preparation by a sol-gel process of TiO2-CeO2 supports (Ce/Ti atomic ratio=1/1) was studied by varying the sol-gel processing conditions. Starting materials were Ti[OCH(CH3)2]4 and CeCl3-7H2O. The samples were characterised before and after calcination at 400 °C by BET, porosity measurements, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Working in acidic conditions leads to the formation of a compound that induces the growth of CeO2 on amorphous TiO2 during calcination. In a basic medium, a well defined CeTiO3 compound is obtained that allows the formation of a real mixed TiO2-CeO2 compound after calcination. It presents a specific area of 70 m2 g−1, a narrow distribution of mesopores and easily reducible cerium oxide.

Growth of CeO 2 thin films by laser ablation

Thin films of CeO 2 have been grown in situ on silicon (111) and silicon (100) by laser ablation. Results from X-ray diffraction θ-2θ scans indicate that both the substrate temperature and the oxygen partial pressure are crucial in promoting growth in the preferential [111] direction

Growth Mechanism of Epitaxial Oxide Films by Laser MBE

ABSTRACTCrystallographic structure and valence state of CeO2 and Nd2-O3 films deposited by laser MBE on Si substrates were investigated by reflection high energy electron diffraction (RHEED) and X-ray photoelectron spectroscopy (XPS). In contrast with epitaxial growth of CeO2 (111) and Nd2O3(111) on Si (111), epitaxial films were not obtained on Si(001). Partially reduced mixed valence (4+ and 3+) Ce was indicated to exist by XPS in the cerium oxide film within 2nm from the interface with Si. Beyond this transition layer, two-dimensional growth of CeO2 film on Si(111) was verified from in situ RHEED and as well as on Si(001) from XPS measurements.

Crystallization and crystal growth of CeO2 under hydrothermal conditions

CeO2 crystals have previously been grown by the flux method [1–4] due to their high melting point and high vapour pressure [5] at high temperatures. The flux method requires high temperatures and generally brings about greater contamination of the flux than does the hydrothermal method. This study deals with the effect of several mineralizers on the crystallization and the crystal growth of CeO2 under hydrothermal conditions.