Publication Date

2014

Document Type

Dissertation/Thesis

First Advisor

Xu, Tao (Professor of chemistry)

Degree Name

Ph.D. (Doctor of Philosophy)

Department

Department of Chemistry and Biochemistry

LCSH

Catalysis||Photoelectrochemistry||Electric batteries||Renewable energy sources||Inorganic chemistry

Abstract

This dissertation investigates two separate clean energy applications, emphasizing material applications and electrochemistry techniques. The first section examines environmentally friendly alternatives for water purification to avoid carcinogenic by-products. To diminish such possibilities, research has shifted towards photoelectrochemical catalysts, such as titanium dioxide (TiO2), because pure TiO2 has limited absorption in the ultraviolet region. Therefore, Ti3+, a self-dopant, has become an attractive candidate for environmentally friendly alternatives. This dissertation demonstrates a novel oxidation procedure to form self-doped Ti3+ in the bulk of rutile TiO2. A brief overview of the work will be given and supporting data including material, methods, structural characterization, photocatalytic activity, and wastewater applications will be discussed. These results displayed a photoactive shift to the visible-light region due to Ti3+ being present within the bulk of the sample, while utilizing a simple industrialization process.||The second section of this dissertation investigates the clean energy application of fuel cells to decrease fossil fuel dependency. Currently, polymer electrolyte fuel cells (PEMFCs) and alkaline fuel cells (AFCs) are the leading candidates for transportation applications due to their capability of producing a high power density, operating at low temperatures, and achieving sufficient travel range between fuel refills. The oxygen reduction reaction (ORR) at the cathode is the rate-limiting reaction for PEMFCs and AFCs versus the hydrogen oxidation reaction at the anode. Thus, the cathode requires a significantly higher electrocatalyst load of platinum (Pt), which is known to be scarce and costly.||The Department of Energy (DOE) has been actively involved in developing highly active, low-cost non-PGM catalysts using metal-organic frameworks (MOFs) as precursors. The second section of this dissertation examines the impact of ORR catalytic activity by MOF-based precursors with various nitrogen-containing organic ligands. The catalyst synthesis, processing, and performance evaluation in both acidic and alkaline media will be discussed. Ligand effects were investigated within MOF -- based precursors to determine their capability of impacting PEMFC and AFC performance. These findings suggest ligands have the ability to enhance catalytic activity, further the improvements of an ORR active catalyst, and eventually replace costly Pt.

Comments

Advisors: Tao Xu.||Committee members: Elizabeth Gaillard; Di-Jia Liu; Lee Sunderlin; Chong Zheng.

Extent

182 pages

Language

eng

Publisher

Northern Illinois University

Rights Statement

In Copyright

Rights Statement 2

NIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors.

Media Type

Text

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