Date of Award

5-2020

Document Type

Thesis

Degree Name

Master of Science (MS)

College/School

College of Science and Mathematics

Department/Program

Chemistry and Biochemistry

Thesis Sponsor/Dissertation Chair/Project Chair

Lynn Schneemeyer

Committee Member

Hendrik Eshuis

Committee Member

Mark Whitener

Abstract

The focus of this thesis is the investigation of ternary and quaternary reduced metal oxide compounds termed “bronzes.” The name bronze originally arose from the metallic-like luster of these compounds. Examples of these compounds range from sodium tungsten oxides to the more complex potassium cesium molybdenum oxides. These compounds are crystalline solids at room temperature.

The “bronzes” are compounds that have been studied since their initial synthesis by Wohler in 1824. These compounds belong to a class of compounds that are known as “nonstoichiometric” compounds. The general formula for reduced ternary transition metal oxides is AxMyOz. In this general formula, the value of x is less than one, but greater than 0. The compounds vary in crystal structures due to the radius of the electropositive element, M. The compounds also vary in physical properties because of their crystal structures and energy level occupations. The compounds can range in color from purple to yellow and range in electrical conductivity from metallic behavior to semiconducting behavior.

The history of these compounds, including a classification of known bronze phases, will be reviewed with a focus on complex molybdate phases. Experimental methods, including experimental searches for new phases using ceramic synthesis techniques and electrolytic growth, and analysis of resulting products by powder x-ray diffraction and SEM studies will be discussed in this thesis. Single x-ray diffraction was utilized as well. The thesis will document the results of the synthetic work aimed at producing new quaternary molybdenum bronze phases. Finally, new quaternary alkali bronze phases containing lithium and potassium, and sodium and potassium will be presented.

File Format

PDF

Included in

Chemistry Commons

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