Development of Novel Electrode Materials for the Electrocatalysis of Oxygen-Transfer and Hydrogen-Transfer Reactions [electronic resource].
- Washington, D.C. : United States. Dept. of Energy, 2002.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
- Physical Description:
- 2,779 Kilobytes pages : digital, PDF file
- Additional Creators:
- Ames Laboratory, United States. Department of Energy, and United States. Department of Energy. Office of Scientific and Technical Information
- Restrictions on Access:
- Free-to-read Unrestricted online access
- Throughout this thesis, the fundamental aspects involved in the electrocatalysis of anodic O-transfer reactions and cathodic H-transfer reactions have been studied. The investigation into anodic O-transfer reactions at undoped and Fe(III)[doped MnO₂ films] revealed that MnO₂ film electrodes prepared by a cycling voltammetry deposition show improved response for DMSO oxidation at the film electrodes vs. the Au substrate. Doping of the MnO₂ films with Fe(III) further enhanced electrode activity. Reasons for this increase are believed to involve the adsorption of DMSO by the Fe(III) sites. The investigation into anodic O-transfer reactions at undoped and Fe(III)-doped RuO₂ films showed that the Fe(III)-doped RuO₂-film electrodes are applicable for anodic detection of sulfur compounds. The Fe(III) sites in the Fe-RuO₂ films are speculated to act as adsorption sites for the sulfur species while the Ru(IV) sites function for anodic discharge of H₂O to generate the adsorbed OH species. The investigation into cathodic H-transfer reactions, specifically nitrate reduction, at various pure metals and their alloys demonstrated that the incorporation of metals into alloy materials can create a material that exhibits bifunctional properties for the various steps involved in the overall nitrate reduction reaction. The Sb₁₀Sn₂₀Ti₇₀, Cu₆₃Ni₃₇ and Cu₂₅Ni₇₅ alloy electrodes exhibited improved activity for nitrate reduction as compared to their pure component metals. The Cu₆₃Ni₃₇ alloy displayed the highest activity for nitrate reduction. The final investigation was a detailed study of the electrocatalytic activity of cathodic H-transfer reactions (nitrate reduction) at various compositions of Cu-Ni alloy electrodes. Voltammetric response for NO₃⁻ at the Cu-Ni alloy electrode is superior to the response at the pure Cu and Ni electrodes. This is explained on the basis of the synergism of the two different metal sites at these binary alloy electrodes acting within the proposed response mechanism. Accordingly, adsorbed H-atoms are generated by cathodic discharge of H⁺ at the Ni-sites whereas adsorption of NO₃⁻ occurs at the Cu-sites.
- Report Numbers:
- E 1.99:is-t 1970
- Other Subject(s):
- Dissertation Note:
- Thesis (Ph.D.); Submitted to Iowa State Univ., Ames, IA (US); PBD: 27 Aug 2002
- Published through SciTech Connect.
Brett Kimball Simpson.
- Funding Information:
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