Doctoral Dissertations

Caleb M. Hull

Keywords and Phrases

Cobalt; Copper; Electrodeposition; Epitaxial; Foil; Single-crystal

Abstract

"Electrochemical deposition methods are presented for the deposition of Co(OH)2 and Cu metal. Paper I shows the deposition of β-Co(OH)2 on Ti through electrochemical reduction of [Co(en)3]3+ to [Co(en)3]2+ in 2M NaOH. The catalytic properties of the deposited Co(OH)2 towards water oxidation is found comparable to Co3O4, with the surface of the Co(OH)2 converting to CoOOH during the reaction. Paper II gives the conditions suitable for epitaxial growth of Co(OH)2 on Au(100), Au(110), and Au(111) following the same reduction mechanism as described in Paper I. The epitaxial films are converted to CoOOH electrochemically or to Co3O4 thermally, each retaining epitaxy to the Au substrate even through drastic structure changes. Epitaxial CoOOH and Co3O4 develop pores and cracks during conversion leading to an increase in the surface area with respect to the initially deposited Co(OH)2 film. Paper III gives conditions for the deposition of epitaxial Cu(100) films on Si(100). This represents only the second metal in the literature to be electrodeposited epitaxially on Si. Cu films are deposited from a dilute pH 3 CuSO4 electrolyte using a two potential step nucleation and growth method. Nucleation occurs at -1.5 VAg/AgCl, a potential negative of the Si oxidation potential, keeping the Si surface reduced and enabling epitaxial nuclei to form. The nuclei are grown at -0.5 VAg/AgCl, a potential positive of the Si oxidation potential, resulting in the concurrent undergrowth of SiOx between the Cu film and Si substrate. Chemical etching of the SiOx with 5% HF allows the Cu film to be separated from the Si substrate yielding a freestanding nanometer thick Cu single-crystal-like foil. Epitaxial Cu films and foils are potentially useful ordered substrates for integrated circuits or flexible electronics"--Abstract, page iv.

Advisor(s)

Switzer, Jay A., 1950-

Committee Member(s)

Choudhury, Amitava
Leventis, Nicholas
Winiarz, Jeffrey G.
Moats, Michael S.

Department(s)

Chemistry

Degree Name

Ph. D. in Chemistry

Sponsor(s)

United States. Department of Energy. Office of Basic Energy Sciences

Comments

This work was supported by the U.S. Department Of Energy, Office of Basic Sciences under Grant No. DE-FG02-08ER46518.

Publisher

Missouri University of Science and Technology

Publication Date

Fall 2018

Journal article titles appearing in thesis/dissertation

  • Deposition of ß-Co(OH)2 films by electrochemical reduction of tris(ethylenediamine)cobalt(III) in alkaline solution
  • Electrodeposition of epitaxial Co(OH)2 on gold and conversion to epitaxial CoOOH and Co3O4
  • Electrodeposited epitaxial Cu(100) on Si(100) and lift-off of single-crystal-like Cu(100) foils

Pagination

xii, 98 pages

Note about bibliography

Includes bibliographic references.

Rights

© 2018 Caleb Michael Hull, All rights reserved.

Document Type

Dissertation - Open Access

File Type

text

Language

English

Thesis Number

T 11421

Electronic OCLC #

1084472875

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