Electrochemistry is the science of electron transfer. The subject is of great importance and appeal because detailed information can be obtained using relatively simple experimental techniques. In general, the raw data is sufficiently complicated to preclude direct interpretation, yet is readily rationalised using numerical procedures. Computational analysis is therefore central to electrochemistry and is the main topic of this thesis. Chapters 1 and 2 provide an introductory account to electrochemistry and numerical analysis respectively. Chapter 1 explains the origin of the potential difference and describes its relevance to the thermodynamic and kinetic properties of a redox process. Voltammetry is introduced as an experimental means of studying electrode dynamics. Chapter 2 explains the numerical methods used in later chapters. Chapter 3 presents a review of the use of nanoparticles in electrochemistry. Chapter 4 presents the simulation of a random array of spherical nanoparticles. Conclusions obtained theoretically are experimentally confirmed using the Cr<sup>3+</sup>/Cr<sup>2+</sup> redox couple on a random array of silver nanoparticles. Chapter 5 presents an investigation into the concentration of supporting electrolyte required to make a voltammetric experiment quantitatively diffusional. This study looks at a wide range of experimental conditions. Chapter 6 presents an investigation into the deliberate addition of insufficient supporting electrolyte to an electrochemical experiment. It is shown that this technique can be used to fully study a stepwise two electron transfer. Conclusions obtained theoretically are experimentally confirmed using the reduction of anthracene in acetonitrile. Chapter 7 presents a new method for simulating voltammetry at disc shaped electrodes in the presence of insufficient supporting electrolyte. It is shown that, under certain conditions, the results obtained from this complicated simulation can be quantitatively obtained by means of a much simpler ‘hemispherical approximation’. Conclusions obtained theoretically are experimentally confirmed using the hexammineruthenium ([Ru(NH<sub>3</sub>)<sub>6</sub>]<sup>3+</sup>/[Ru(NH<sub>3</sub>)<sub>6</sub>]<sup>2+</sup>) and hexachloroiridate ([IrCl<sub>6</sub>]<sup>2−</sup>/[IrCl<sub>6</sub>]<sup>3−</sup>) redox couples. Chapter 8 presents an investigation into the voltammetry of stepwise two electron processes using ionic liquids as solvents. It is shown that these solvents can be used to fully study a stepwise two electron transfer. Conclusions obtained theoretically are experimentally confirmed using the oxidation of N,N-dimethyl-p-phenylenediamine in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([C<sub>4</sub> mim][BF<sub>4</sub>]). The work presented in this thesis has been published as 7 scientific papers.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:581042 |
| Date | January 2012 |
| Creators | Belding, Stephen Richard |
| Contributors | Compton, Richard G. |
| Publisher | University of Oxford |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://ora.ox.ac.uk/objects/uuid:e997642f-fbaa-469c-98a3-f359b0996f03 |
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