No description available.

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Thesis (Ph. D.)--Florida State University, 2003. / Advisor: Dr. Adriana Moreo, Florida State University, College of Arts and Sciences, Dept. of Physics. Title and description from dissertation home page (viewed Apr. 9, 2004). Includes bibliographical references.

No description available.

Thesis (Ph.D.) -- McMaster University, 1997 / Includes bibliographical references Also available via World Wide Web.

Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Dr. Jack Crow, Florida State University, College of Arts and Sciences, Dept. of Physics. Title and description from dissertation home page (viewed Jan 18, 2005). Includes bibliographical references.

Thesis (Ph.D.)--McMaster University, 2003. / Advisor: John E. Greedan. Also available via World Wide Web.

Thesis (Ph. D.)--State University of New York at Binghamton, Department of Chemistry, 2005. / Includes bibliographical references.

The first study investigated the deposition and characterization of the CoO and Co3O4 phases of cobalt oxide. It was determined that both phases can be easily distinguishable by XPS, LEED and EELS and grown by only altering the oxygen partial pressure during MBE deposition. This fundamental knowledge gives a foundation for further experiments involving graphene growth on cobalt oxides. The second study focused on the layer-by-layer growth of graphene on another metal oxide, MgO. Past research gives promise of favorable interfacial interactions at the graphene/MgO interface though the exact growth mechanism is unknown. Layer by layer growth by MBE resulted in the characterization of a complex graphene oxide/buckled graphene/ graphene heterostructure confirmed by XPS, AES, LEED and EELS and supported by DFT calculations performed by the project's collaborators at the California Institute of Technology. This detailed look into graphene growth give valuable information that can be allied to graphene growth on similar oxide surfaces. The last project deviates from graphene-based studies and instead focused on interfacial interactions between two metal oxides, chrome oxide and titanium oxide. A corundum phase TiO2-x film was grown on Al2O3 via MBE and characterized using XPS, AES, LEED, and EELS. Data taken gives evidence of the presence of a two-dimensional election gas at the TiO2-x surface because of oxygen vacancies present after deposition. Deposition of chrome in UHV results in the formation of an oxidized chrome overlayer by abstraction of oxygen from the TiO2-x underlayer increasing the number of vacancies present. MOKE measurements taken by the project's collaborators at the University of Nebraska-Lincoln indicate that there is an interfacial exchange bias at the interface of the two oxides, a favorable property for magnetic device applications.

In this dissertation, I present four projects on the fundamental study of the surface configurations and reactivity of the metal oxides using density functional theory computational method. In the first project, we studied the formaldehyde adsorption and diffusion on rutile TiO2 (110) surface. By comparing the adsorption of formaldehyde on stoichiometric and defective TiO2 surfaces under the same condition, we evaluated the effect of surface oxygen vacancy on their interaction with formaldehyde. The project involved close collaboration with Dr. Zhenrong Zhang’s group of Baylor University who studied the formaldehyde chemistry on rutile TiO2(110) surface using a combination of STM and other surface science techniques. In the second project, we compared the surface chemistries of formaldehyde and formic acid on rutile TiO2 and SnO2, two structurally similar but chemically different oxides. We analyzed the oxidation of formaldehyde to formic acid on two oxides and assessed the role of surface oxygen in the oxidation. In the third project, we studied the oxygen evolution reaction (OER) catalyzed by γ-FeOOH (010) under the alkaline condition. The OER process was divided into four elementary steps and the potential energy profiles of these steps on three terminations of the γ-FeOOH (010) surface were mapped out. Based on the computed reaction energies, we determined the most probable OER reaction pathway on each surface termination. We found that partially exposed surface Fe sites were the active sites for the OER process. In the fourth project, we studied the potential of iron oxides (FeOx) and iron-titanium mixed oxides (FeTiOx) as solid oxygen carriers for the chemical looping combustion (CLC) process. As oxygen carriers for CLC, FeOx and FeTiOx in fully oxidized forms went through a series of reduction steps by reacting with the fuel molecules. The reduced oxides were then re-oxidized in an air reactor to restore their oxygen. By studying the surface oxygen vacancy formation and oxygen diffusion, we gained insights into the initial stage of reduction process and activities of FeOx and FeTiOx as well as the effect of Ti on oxygen carrying properties of FeTiOx for CLC.