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Dissertations / Theses on the topic 'Electrochemistery'
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1
Brookes, Benjamin A. "Computational electrochemistry." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270000.
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Fisher, Adrian Charles. "Mechanistic electrochemistry." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293419.
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Klymenko, O. V. "Computational electrochemistry." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409030.
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Hunt, Nicholas Imber. "Biological electrochemistry." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386592.
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Lane, R. L. "Semiconductor electrochemistry." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370280.
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Melville, James. "Computational electrochemistry." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249179.
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Thompson, Mary. "Computational electrochemistry." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432256.
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Chevallier, François Gregory. "Computational electrochemistry." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433380.
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Alden, John. "Computational electrochemistry." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297935.
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Du, G. "Computational electrochemistry." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598660.
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This thesis describes the development and application of the lattice Boltzmann method for the investigation of electrolysis mechanisms. Hydrodynamic, mass transport and potential distributions models have been implemented by this method and used to simulate the different electrochemical problems. Chapter 2 introduces a Lattice Bhatnagar-Gross-Krook (LBGK) model, the simplest and most popular lattice Boltzmann method. The theory and implementation of the LBGK for hydrodynamic and mass transport were demonstrated. Chapter 3 describes the development of two and three-dimensional lattice Boltzmann models for the simulation of a reversible system for a range of microelectrode geometries under the measurement of potential step, linear sweep and the cyclic voltammetry. Excellent agreement between the numerical models and the analytical solutions was observed. To illustrate the flexibility of the lattice Boltzmann method the simulation of the current response for a range of electrode geometries, distorted from microband electrode geometries the micro hemicylinder electrode, is also described. Chapter 4 investigates the modification of voltammetric behaviour when an obstruction was placed close to a working electrode. The current responses are largely affected by the position and shape of the obstruction. Chapter 5 details the lattice Boltzmann hydrodynamic and mass transport model in a rectangular duct and clearly shows the influence of chronoamperometric behaviour affected by the channel edge. The current responses of the suspended square cylinder shaped electrodes have also been investigated. In the final results chapter the influence of IR drop on the shape of the current voltage curves is demonstrated. The model has been extended to simulate two generator-collector systems, demonstrating the ability of the numerical model to be used for simulating different geometries.
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Henley, Iain. "Computational electrochemistry." Thesis, University of Bath, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410800.
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Gooch, Kerry A. "Numerical electrochemistry." Thesis, University of Bath, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425881.
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Zhou, Yan. "Molecular electrochemistry." Thesis, University of Hull, 2012. http://hydra.hull.ac.uk/resources/hull:7072.
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Belding, Stephen Richard. "Computational electrochemistry." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:e997642f-fbaa-469c-98a3-f359b0996f03.
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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 Cr3+/Cr2+ 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(NH3)6]3+/[Ru(NH3)6]2+) and hexachloroiridate ([IrCl6]2−/[IrCl6]3−) 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 ([C4 mim][BF4]). The work presented in this thesis has been published as 7 scientific papers.
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Menshykau, Dzianis. "Computational electrochemistry." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:64e553c7-1bd2-429d-a5de-aeb4a29fc067.
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This thesis addresses simulation of electrochemical experiments, with an emphasis on processes of diffusional mass transport to electrode surface. Following system has been studied: • Applying theoretical modeling and experimentation is shown that even significant surface roughness produced by deliberate polishing or scratching is not sufficient to be distinguished in cyclic voltammetry experiments conducted under the usual conditions. In stripping voltammetry experiment the shape of the voltammograms strongly depends on the model of the electron transfer but is not always sensitive to the precise model of the electrode surface; the conditions under which this is the case are identified, and generic roughness effects on stripping voltammetry are quantified. Electrode roughness can have a significant effect on the stripping of the metals from the solid electrode especially in respect of the voltammetric waveshape. • We first consider two different models of electrodes covered with electroinactive layers: the electrode is covered with a uniform layer and the layer contains pinholes. Both models are simulated and then compared to identify conditions under which they can be distinguished. Next we propose generic model to predict the influence of electroactive layer on the cyclic voltammetric. The conditions under which deviation from the behavior of a planar electrode are predicted. • We first consider one electron, one proton and next two electron, two proton reduction of surface bound species. Two mechanisms of reaction are considered: stepwise and concerted. Voltammetry studied under the three regimes of protons mass transport: infinitely fast (fully buffered solution), infinitely slow (infinitely high surface coverage of electrode) and intermediate case of finite rate of diffusional mass transport to electrode surface. Types of voltammograms observed in each case are presented and discussed. • Theory of chronoamperometry on disc and ring-recessed microelectrodes and their arrays is reported. Three and four different regimes of transient current versus time can be observed at microelectrode arrays of disc and ring electrodes, accordingly. A generic, accurate and easy to use method of experimental chronoamperometric data analysis is proposed. It is shown that the method can be applied to the simultaneous measurement of D and nC in solution. • The fabrication, characterization, and use of arrays of ring-recessed disk generator-colector microelectrodes are reported. Experiments and simulations relating to time- of-flight experiments in which material electrogenerated at a disk is diffusionally transported to the ring are reported. We further study voltammetry of electrochemically active species which undergoes first and second order chemical reactions. Current transients are found to be sensitive to the diffusion coefficient of both the reduced and oxidised species as well as to the rate of the chemical reaction and its mechanism.
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Williams, Nia Ann. "Mechanistic electrochemistry." Thesis, University of Bath, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341638.
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Sala, Alexandre. "Synthèse et caractérisation de polymères à empreintes ionique du cuivre pour la conception d'électrodes modifiées." Electronic Thesis or Diss., Toulon, 2022. http://www.theses.fr/2022TOUL0010.
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L’utilisation du cuivre en tant qu’agent biocide dans les revêtements anti-salissures sur les bateaux a provoqué son accumulation dans les eaux portuaires. Le but de ces travaux de thèse est de développer des capteurs électrochimiques permettant sa détection dans des échantillons marins. Pour cela des polymères à empreintes du cuivre(II) ont été élaborés et utilisés pour la modification d’électrodes.Dans un premier temps, des particules de polymères à empreintes ont été synthétisées à l’aide d’un agent réticulant (le diméthacrylate d’éthylène glycol ou le N,N’-méthylène-bis-acrylamide) et d’un monomère fonctionnel, la méthacrylamido-L-histidine (MAH) qui permet la formation d’un complexe avec le cuivre(II). La caractérisation physico-chimique a permis de confirmer la bonne intégration de la MAH et d’évaluer les propriétés morphologiques des polymères.Les propriétés de rétention du cuivre(II) ont ensuite été étudiées et les particules présentant les meilleures performances ont été utilisées pour la fabrication d’électrodes à pâte de carbone. Ces électrodes, avec une limite de détection de 5,9 x 10-2 μM (ou 3,75 μg/L), ont permis la détermination de cuivre(II) dans des échantillons marins.Enfin, de nouvelles voies de modifications de surface ont été explorées pour la formation de film polymère in situ. Ainsi, des iniferters ont été greffés sur des électrodes en or par formation de mono-couches auto-assemblées mais aussi par électropolymérisation d’un polymère avec des fonctions iniferters pendantes. Cette dernière voie a permis de photopolymériser un film de polymère à empreintes du cuivre(II) sur une électrode de carboneThe use of copper as a biocide in anti-fouling coatings on ships has led to its accumulation in harbour waters. The aim of this work is to develop electrochemical sensors for its detection in marine samples. For this purpose, copper(II)-imprinted polymers were prepared and used for the modification of electrodes.Firstly, imprinted polymer particles were synthesised using a cross-linking agent (ethylene glycol dimethacrylate or N,N'-methylene-bis-acrylamide) and a functional monomer, methacrylamido-L-histidine (MAH), which can form a complex with copper(II). The physico-chemical characterization of the polymer particles confirmed the integration of MAH and allowed to evaluate the morphological properties of the polymers.The copper(II) binding properties were then evaluated and the particles with the best performance were used to make carbon paste electrodes. These electrodes, with a detection limit of 5.9 x 10-2 μM (or 3.75 μg/L), allowed the determination of copper(II) in marine samples.Finally, new approaches for surface modification were explored for in situ polymer film formation. Thus, iniferters were grafted onto gold electrodes by the formation of self-assembled monolayers but also by electropolymerisation of a polymer with pendant iniferter functions. The latter route allowed the photopolymerisation of a copper(II)-imprinted polymer film on a carbon electrode
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Taylor, Alasdair W. "Electrochemistry In Vacuo." Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.523505.
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Oliver, B. Nigel. "Electrochemistry of metalloproteins." Thesis, University of Oxford, 1985. http://ora.ox.ac.uk/objects/uuid:0fddb16d-0dd1-42ab-a3b5-f1dc73bc922b.
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The direct (unmediated) electrochemistry of a variety of redox proteins has been studied at a range of electrode materials. Electrochemical studies using cytochromes, iron-sulphur proteins and copper proteins show a marked enhancement of the heterogeneous electron-transfer rate at the "edge" plane of pyrolytic graphite. Parallel ESCA studies have shown that mechanical polishing of edge graphite provides an electrode with a high surface coverage of oxidised functional groups. These results indicate the importance of oxidised functional groups in facilitating productive interactions with the proteins. The importance of multivalent cations has also been established. For proteins with negatively-charged physiological interaction domains, such as plastocyanin or 2[4Fe-4S] ferredoxin, elect reactivity at "edge"-oriented graphite is promoted and stabilised in the presence of multivalent cations such as Cr(NH,sub>3)63+. On the other hand, the electrochemistry of positively-charged cytochrome ̲c is inhibited and destabilised in the presence of such cations. Promotion and inhibition profiles for a range of proteins, together with various cations, indicate the participation of specific electrode-cation-protein interactions. Studies on plastocyanin, whose electrochemistry is troubled by a time-dependent deterioration of response, have demonstrated the importance of low protein concentration, low pH, low temperatures (3°C) and, in particular, Pt(NH3)64+ at stabilising faradaic responses. Surface modification of edge pyrolytic graphite has been achieved electrochemically by exploiting the contrasting substitutional reactivity of chromium(III) and chromium(II). The modified-surface, incorporating chromium(III) complexes, promoted reversible direct electrochemistry of plastocyanin. The direct electrochemistry of plastocyanin, at pH 4, has provided an insight into the possible importance of a kinetically-inactive protonated form of the reduced protein. The t1/2 for deprotonation of Cu(I)-plastocyanin is estimated to be < 1 ms. Finally, the direct electrochemistry of azurin was exploited in the design of an electrocatalytic system. The electrochemical oxidation of p-cresol to p-hydroxybenzaldehyde was effected enzymically.
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Saidi, Mohammed-Yazid. "Electrochemistry of intercalation." Thesis, Heriot-Watt University, 1991. http://hdl.handle.net/10399/845.
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Kang, Minkyung. "Single nanoparticle electrochemistry." Thesis, University of Warwick, 2017. http://wrap.warwick.ac.uk/99424/.
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This thesis presents various pipette-based techniques for resolving the electrochemical activities of single nanoentities (e.g., nanoparticles, NPs) in time and/or space. In particular, the work provides a framework for understanding the (electro)chemistry of single NPs and the development of tools to resolve them temporally and/or spatially. Through the use of the state-of-the-art instrumentation developed by the Warwick Electrochemistry & Interfaces Group (WEIG), electrochemical measurements with a “static” probe (i.e., micro-droplet electrochemical cell) have revealed detailed (temporally-resolved) information on the dynamics of the interaction of colloidal NPs (in solution) with electrode surfaces. Through careful data analysis, and supported by simulations, it has been demonstrated how current-time traces provide information on the physical dynamics of individual NPs on an electrode surface. This regime has been further applied to understand the electrodissolution of individual NPs and has revealed the complexity of the process, through carefully designed experiments and thorough quantitative analysis of large data sets. In addition, through the use of the aforementioned instrumentation, new scanning electrochemical probe microscopy (SEPM) regimes have been developed with a “dynamic” probe, providing spatial resolution. A greatly simplified nanoprobe configuration (i.e., a single channelled probe) has been proposed for simultaneous topography and electrochemical flux mapping at the nanoscale, implemented with a new scanning protocol in scanning ion conductance microscopy (SICM). This was directly applied in tandem with FEM simulations to observe and explain heterogeneities in the ion flux at and around individual catalytic NPs adhered to an inert conductive surface during catalytic turnover conditions with electrochemical activity information on surface heterogeneities at the nanoscale. Finally, to highlight the generalities of the approaches, a new configuration of scanning electrochemical microscopy (SECM) combined with SICM with a double-channelled nanoprobe has been introduced, demonstrating the simultaneous visualisation of topography and uptake rate on a biological entity (cell), which is quantified by finite element method (FEM) simulations. In this configuration the probe is multifunctional, delivering analytes to the cell surface, providing probe positional information and detecting changes in the uptake rate of electroactive molecules across the interface.
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Su, Wen-Ta. "Electrochemistry in supercritical fluids." Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.537675.
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Fitzgerald, A. M. "Electrochemistry in ionic liquids." Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419511.
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Brooks, C. B. "Electrochemistry in ionic liquids." Thesis, Queen's University Belfast, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401797.
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Latto, Matthew Neil. "The electrochemistry of diamond." Thesis, University of Bristol, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247232.
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Dabo, Ismaila. "Towards first-principles electrochemistry." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44320.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2008.Includes bibliographical references (p. 143-151).
This doctoral dissertation presents a comprehensive computational approach to describe quantum mechanical systems embedded in complex ionic media, primarily focusing on the first-principles representation of catalytic electrodes under electrochemical conditions. The accurate electrostatic description of electrified metal-solution interfaces represents a persistent challenge for ab-initio simulations and an essential requisite for predicting the electrical response of electrochemical convertors-i.e., the correspondence between the macroscopic voltage and the microscopic interfacial charge distribution. The approach consists of controlling the electrode voltage via its conjugate extensive variable, namely, the charge of the system. As a preliminary to the study of electrified interfaces in ionic media, we analyze charged slabs in vacuum subject to periodic boundary conditions. We show that the corrective potential (defined as the difference between the exact open-boundary potential and the periodic potential obtained from a Fourier transform) varies smoothly over space, allowing for its determination on a coarse mesh using optimized electrostatic solvers. Because this scheme takes into account exact open boundary conditions, its performance is considerably superior to that of conventional corrective methods. Extending this computational scheme, we present an efficient approach to model electrochemical systems under realistic conditions, based on a first-principles description of the interface region and on a continuum representation of the ionic solvent.
(cont.) We demonstrate that the ionicsolution contribution to the electrostatic potential-the ionic solvent reaction field--can be computed independently at low cost simultaneously using fast Fourier transforms and multigrid techniques, and highlight the importance of adopting adequate electrochemical boundary conditions to correctly predict the electrical response of electrode-electrolyte interfaces. In order to probe and validate the electrochemical model, we study the vibrational Stark effect-i.e., the influence of the applied voltage on the vibrational properties-for carbon monoxide adsorbed on transition metal surfaces, a phenomenon whose description requires an accurate representation of the interfacial electric field. We start out the analysis by examining the vibrational properties of CO adsorbed on clean and ruthenium-covered platinum substrates. The calculated C-O stretching frequencies are found to be in excellent agreement with experimental measurements despite the frequent qualitative failures of local and semilocal exchange-correlation functionals in predicting adsorption energies for CO on transition metals. We then introduce an orbital-resolved force analysis to clarify the electronic origins of the C-O red shifts, and present a sensitivity analysis to assess the influence the HOMO and LUMO hybridizations on the calculated frequencies, thereby establishing the remarkable accuracy of conventional density-functional theory methods in determining the vibrational properties of adsorbed CO. Based on these results, we apply the electrochemical model to provide the first comprehensive ab-initio description of the vibrational Stark effect for CO on transition metal surfaces, finding excellent agreement with spectroscopic measurements.
(cont.) As related projects, we have implemented a molecular-dynamics algorithm for metallic systems and developed a self-interaction correction method to rectify the tendency of density-functional theory calculations to overestimate binding energies. The present computational electrochemistry toolkit open promising perspectives for the application of first-principles methods to assist the microstructural engineering of electrochemical convertors.
Ismaila Dabo.
Ph.D.
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Jiao, Xue. "Electrochemistry of platinum nanoparticles." Thesis, University of Oxford, 2018. http://ora.ox.ac.uk/objects/uuid:5652b2fa-92cd-4ea6-829c-03c6f4b230dd.
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This thesis reports experimental work with two main aims: the first is the investigation of single nanoparticles with an emphasis on their porosity, and the second is to develop a more comprehensive understanding of their electrocatalytic behavior. The fundamental principles and techniques of electrochemistry are introduced in Chapter 1. Chapters 2 and 3 respectively summarize nanomaterials and their characterization methods. In particular, the technique of single particle electrochemical impacts, so-called "nanoimpacts", is used to study redox reactions at individual nanoparticles. Chapters 4 and 5 report the porosity of platinum nanoparticles (PtNPs) via tag-redox coulometry (TRC) and surface platinum oxidation, respectively. In the former, thioltagged PtNPs are employed and current transients upon impacts with a cathode are detected. This is due to the nitro group reduction on individual PtNPs. The charge per spike is measured and the number of tag molecules can be calculated. Therefore, the "electroactive surface area" of the PtNPs is revealed. In the latter, oxidative transients upon direct impacts are observed. The charge per current spike is measured and attributed to the formation of surface platinum oxides. XPS shows PtO and PtO2 in different amounts and an average oxidation state is deduced as a function of potential. Thus the number of platinum atoms oxidized per PtNP can be estimated. Both experiments allow insight into extent to which the internal surface of the aggregate is "seen" by the solution and is electrochemically active, providing a fuller knowledge of the catalytic behavior of nanoparticles, as reflected from the reaction kinetics and the redox currents. Furthermore, results from Chapters 4 and 5 are in close agreement with each other, indicating the accuracy of the measurements in both studies. With this appreciation of the internal nanoscale structure, Chapter 6 investigates the kinetics of the hydrogen oxidation reaction (HOR) on mesoporous particles. The steadystate current for HOR is measured on both individual platinum particles and PtNPs drop-casted substrates. The kinetic parameters are determined and contrasted between these two approaches. Nanoimpacts are required in order to correctly understand the electrochemical reaction catalyzed by nanoparticles, as the aggregation or loss of ensemble drop-casted particles leads to errors. Chapter 7 further elaborates the role of nanomorphology of nanoparticles in catalyzing the HOR using individual mesoporous particles and low density random arrays of particles. At the single particle scale the activity of the platinum catalyst towards the hydrogen oxidation is potential dependent and exhibits two peaks, as reflected in the electrochemical current. This is due to the sensitivity of the reaction rate to the interfacial structure of PtNPs. The decrease in activity correlates directly with the potential at which the underpotential deposited hydrogen (Hupd) is removed from the catalytic interface. The contribution of the internal mesoporous nanoparticle structure towards the total particle catalytic activity is further corroborated through comparison of the current-time transients recorded for individual nanoparticles of differing morphology: solid vs mesoporous, and by evidencing the sensitivity of the single particle catalytic activity to the supporting electrolyte concentration. In Chapter 8, the underpotential deposition and removal of hydrogen from a mesoporous PtNP surface is shown to quantify the electrochemically active surface area (ECSA) of an individual nanoparticle. This surface area of the particle is concomitantly correlated with its individual catalytic activity (current density) towards the hydrogen evolution reaction (HER). In addition, conclusions in this chapter are compared with the results in Chapters 4 and 5, showing consistency in all structural measurements of the particles. Finally, Chapter 9 provides the main conclusions for the studies described in the thesis. The various discoveries in this thesis in respect of individual nanoparticles reflect generic methodological development, both fundamentally and applied, in studying electrochemistry at nanoscale. The overall major finding is that it is essential to recognize particle porosity to fully understand catalytic properties.
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Li, Xiuting. "Electrochemistry of single nanoparticles." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:1ea3a662-242d-4734-a4da-25765fad4427.
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This thesis presents experimental work with two main aims: one is the detection and characterization of single electrocatalytic nanoparticles with an emphasis on metal nanoparticle decorated carbon nanotubes, and the other is to develop a more comprehensive understanding of nanoscale electrocatalysis by exploring the differences in the electrocatalytic behaviour of single nanotubes as compared to their ensembles. The first chapter introduces the basic principles and techniques of electrochemistry and the second chapter gives a brief introduction to the nanomaterials and electrochemical methods used in this thesis. Chapter 3 first reports the detection of individual carbon nanotubes with the 'nano-impact' method using the production of the under-potential deposited hydrogen (HUPD) from proton reduction on palladium nanoparticle decorated carbon nanotubes (CNT-Pds). The current spikes corresponding to the reduction of proton forming HUPD on the individual impacting CNT-Pds were detected via chronoamperometry. From the knowledge of the palladium nanoparticle sizes and their coverage on the CNTs it was further demonstrated how the magnitude of impact charge allows an assessment of the nanotube lengths. The correspondence between electrochemical sizing and microscopy results directly shows that a CNT-Pd is electroactive along its entire length, evidencing the reactivity and conductivity of the CNTs and further indicating the complete HUPD saturation of the palladium nanoparticles decorated on the carbon nanotubes. Chapter 4 then extends electrocatalytic nano-impacts of single CNT-Pd to investigate the hydrogen oxidation reaction (HOR). A facile procedure which enables rapidly and easily gathering single nanotube voltammetry was established and validated. Single CNT-Pds impact a micro wire electrode from dilute suspension and adhere to it for a sufficiently long time for cyclic voltammetry to be conducted. The single adsorbed decorated CNT is electro-catalytic towards HOR which thus occurs exclusively on it and cyclic voltammetry on single decorated carbon nanotube is realized. Single nanotube voltammetry of oxygen reduction reaction (ORR) was further studied and reported in Chapter 5. It demonstrates that the reduction of oxygen on Pd involves the initial formation of absorbed superoxide with fast electron transfer kinetics but with a low apparent transfer coefficient due to double layer effects arising from the Coulombic interactions of the adsorbed superoxide species inside the double layer. The mechanism of ORR on Pd was re-evaluated. Chapter 6 compares the oxidation of formate and of methanol at the single CNT-Pds and ensemble levels. Pd oxide formation as a competitive reaction with formate or methanol oxidation is significantly inhibited at high overpotentials at single nanotubes in comparison with what is seen with ensembles. The discovery of the superior electro-catalytic performance under high mass transport conditions created by single nanotubes suggests requirements for the design of better fuel cell development and offers the scope for new catalytic approaches to be developed. Chapter 7 is focused on the study of the origins of the current fluctuation observed in the single nanotube voltammetry by comparing the responses of HOR at a single CNT-Pds immobilised on the gold surface to analogous data on a carbon substrate. No significant distinction between the gold and carbon was found, demonstrating that the physical motion of the nanotube at the electrode is likely responsible for the modulation of current. A simple and feasible methodology based on the 'nano-impact' method is then developed to enable the measurement of the resistance across individual carbon nanotube-electrode contacts. It reveals that the major component of the measured resistance is associated with the single CNT-gold contact, which has major implications for the widespread use of CNTs as electro-catalysts and as catalyst supports.
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Toh, Her Shuang. "Electrochemistry of silver nanoparticles." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:7b9c8a2f-6599-446e-a0b3-cb33ca39e476.
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This thesis presents findings realising two main objectives. The first aim is to investigate the electrochemical detection of nanomaterials with an emphasis on silver nanoparticles. The second goal is to employ silver nanoparticles in electroanalysis to aid in the detection of other analytes. First, the detection of silver nanoparticles was demostrated through two different electrochemical methods, stripping voltammetry and 'nano-impacts'. For stripping voltammetry, the potential of metallic nanoparticles oxidation was quantified by various new analytical expressions for peak potential. For the novel method of 'nano-impacts', individual silver nanoparticles were successfully detected in an optically opaque suspension. Then, a comparison between the two techniques was achieved via the oxidation of silver nanoparticles with different capping agents. Strong capping agent effects was found for stripping voltammetry and one may markedly underestimate the amount of silver nanoparticle present on the electrode surface. The electrochemical sizing of nanoparticles via 'nano-impacts' remained unaffected by the capping agent effect. Amidst the study on the various types of capping agent, it was discovered that cetyltrimethylammonium bromide (CTAB) is electroactive due to the oxidation of its bromide content. This inspired the use of 'nano-impacts' to detect the presence of large CTAB micelles which self-assembled at concentrations above the critical micelle concentration. Next, various types of silver nanoparticles were applied to different electroanalytical systems to aid in the measurement of other analytes. (a) Small silver nuclei, remaining after the oxidative stripping of an electrode modified by silver nanoparticle suspension drop casting, allowed subsequent signal enhancement (at least a factor of three) in anodic stripping voltammetry of silver ions. (b) The thermodynamic favourable formation of silver halide complexes allowed the silver nanoparticle modified electrode to analyse the halide content of a solution. Hence, a proof-of-concept for an electrochemical sensor based on silver nanoparticle modified electrode for chloride ions was established. This might be applied to the pre-screening of cystic fibrosis, a genetic disease detrimental to many infants' lives. (c) Another key halide in human body, iodide ions, was also measured using a related concept. The level of iodide ions in synthetic human urine was determined. Last, the strong affinity of silver to thiol groups also warranted a study devoted to their interaction through electrochemical and spectroscopic measurements. It was found that there is no general mechanism for silver-thiol interaction and each thiol must be treated as a separate entity.
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Xiao, Shaorong. "The electrochemistry of phenothiazine derivatives." Thesis, University of Central Lancashire, 2000. http://clok.uclan.ac.uk/20876/.
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Methylene blue derivatives (MBDs) such as methylene blue (MB -), 1-methyl methylene blue (1MMB) and 1,9-dimethyl-methylene blue (DMMB) have potential use as drugs within photodynamic therapy (PDT). Knowing the redox properties of MBDs will help in understanding the way in which MBDs interact with a range of biological systems. In this work, the electrochemical behaviour of MBDs at various solution pHs have been studied for the first time on gold microdisc electrodes using steady state and non-steady state cyclic voltammetric methods. Steady-state studies The reduction of MBDs is an ECE(CC) process where the C steps are protonation reactions. The number (m) of W participating in the overall electrode process increases from 1 to 2 or 3 with decreasing pH although the profile is different among MBDs. The half-wave potential (E 112) of each methylene blue derivative (MBD) shifts to more negative potential with increasing pH values. The E 112 of MBD at the same pH shifts to more cathodic potentials with an increasing number of -CH 3 substituent, indicating that the thermodynamic facility of MB, lMMB and DMMB reduction decreases with increasing the number of -CH3 substituents. The reduction products of MBDs depend strongly on pH, sweep rate, and sweep potential limit, as well as number of -CH 3 substituents. Non-steady state studies The redox behaviour of MBDs under non-steady-state conditions is complicated. Their common characteristics are that (i) the initial reduction of MBD is a diffusion controlled process; (ii) the onset potentials for MBD reduction shift to more negative potentials with increasing pH and number of CH 3 substituents; (iii) the facility of observation of the charge transfer complex increases with increasing pH; (vi) the charge transfer complex can be further reduced at more cathodic potentials; and (v) the amounts of charge transfer complex and leuco form depend on sweep rate and sweep potential window. They also have some differences among the electrochemical behaviour of the three drugs, such as, some anodic and cathodic processes may occur in one of MBDs, and some may not. Possible mechanisms for the electroreduction of MBDs are suggested and discussed in the light of the effect of pH and potential sweep rate on the reaction products.
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Noël, James J. "The electrochemistry of titanium corrosion." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0028/NQ51663.pdf.
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Basura, Vesna Ivana. "Electrochemistry of proton exchange membranes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0011/NQ61625.pdf.
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Wain, Andrew John. "Electron spin resonance in electrochemistry." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.432259.
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Dickinson, Edmund John Farrer. "Charge transport dynamics in electrochemistry." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:e4acac56-7265-49ec-9a36-49b3ae6729ed.
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Electrolytic solutions contain mobile ions that can pass current, and are essential components of any solution-phase electrochemical system. The Nernst–Planck–Poisson equations describe the electrodynamics and transport dynamics of electrolytic solutions. This thesis applies modern numerical and mathematical techniques in order to solve these equations, and hence determine the behaviour of electrochemical systems involving charge transport. The following systems are studied: a liquid junction where a concentration gradient causes charge transport; an ideally polarisable electrode where an applied potential difference causes charge transport; and an electrochemical cell where electrolysis causes charge transport. The nanometre Debye length and nanosecond Debye time scales are shown to control charge separation in electrolytic solutions. At equilibrium, charge separation is confined to within a Debye length scale of a charged electrode surface. Non-equilibrium charge separation is compensated in solution on a Debye time scale following a perturbation, whereafter electroneutrality dictates charge transport. The mechanism for the recovery of electroneutrality involves both migration and diffusion, and is non-linear for larger electrical potentials. Charge separation is an extremely important consideration on length scales comparable to the Debye length. The predicted features of capacitive charging and electrolysis at nanoelectrodes are shown to differ qualitatively from the behaviour of larger electrodes. Nanoscale charge separation can influence the behaviour of a larger system if it limits the overall rate of mass transport or electron transfer. This thesis advocates the use of numerical methods to solve the Nernst–Planck–Poisson equations, in order to avoid the simplifying approximations required by traditional analytical methods. As this thesis demonstrates, this methodology can reveal the behaviour of increasingly elaborate electrochemical systems, while illustrating the self-consistency and generality of fundamental theories concerning charge transport.
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Whitaker, Richard George. "The electrochemistry of redox enzymes." Thesis, University of Warwick, 1989. http://wrap.warwick.ac.uk/4235/.
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The work presented in this thesis is of two types. Firstly methods for the electrochemical immobilisation of redox enzymes in organic polymers are described. The electrochemical monitoring of the immobilised enzyme reaction by detection of one of the enzyme's products is discussed, and the results obtained for such a system under a variety of experimental conditions are presented. A good understanding of the way in which such a system operates' was obtained by using a specially developed kinetic model., This model is explained fully in the theory chapter of this thesis. A variety of organic polymers were used in the electrochemical immobilisation process, with varying degrees of success. The flexibility of this approach is demonstrated by the use of a variety of immobilisation matrices and also by the development of bienzyme and bilayer devices. The final experimental chapter presents work on the covalent modification of redox enzymes with a variety of, redox centres based. on ferrocene. Although attempts to electrochemically immobilise a modified enzyme were not successful, some interesting information about the kinetic behaviour and stability of a series Of modified enzymes was obtained. An indication of possible work forming an extension to this thesis is given in the final part of this thesis. The electrochemical immobilisation techniques and the procedure for covalently modifying, enzymes using electroactive, groups are relatively recent ideas. Much work remains to be done before a better understanding of these systems is gained.
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Stevens, Nicholas P. C. "Finite element simulations in electrochemistry." Thesis, University of Bath, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285310.
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McCormack, Sean Patrick. "Electrochemistry in the gas phase." Thesis, University College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415192.
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Silva-Martinez, Susana. "Applications of ultrasound in electrochemistry." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242670.
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Kloppers, Marius Jacques 1962. "Electrochemistry of iron-chromium alloys." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/106706.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1991.Vita.
Includes bibliographical references (leaves 307-314).
by Marius Jacques Kloppers.
Ph.D.
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Dydek, EthelMae Victoria. "Electrochemistry and Electrokinetics in Microchannels." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/70401.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 119-123).
The main body of this work considers the design and development of a microfluidic, continuous electrochemical sensor capable of measuring accurate potential differences. The key challenge in creating such a device is the implementation of a miniaturized reference electrode and salt bridge. The purpose of a salt bridge is to allow ionic conduction between the reference and working electrodes while maintaining a physical separation between the two systems. Macro reference electrode and salt bridge techniques are difficult to implement on a micro scale. Instead of attempting to conform one of these techniques to function in a micro system, new methods were developed that take advantage of the conditions in a continuous microfluidic device. In particular, laminar flow and slow relative diffusion times allow for a reference electrode that does not require a physical salt bridge. Ionic conduction is maintained between neighboring reference and analyte streams while slow mixing effectively separates the two systems. Several different device designs were investigated focusing on the prevention of reference electrode contamination. If the reference electrode is chemically contaminated it will no longer behave as expected and can not be used as a reference point. Contamination at the reference electrode was evaluated while varying flow rates and the geometry of the microfluidic device. Mathematical models were simulated in order to understand the mass transport in each device design. Based on these simulations, dimensionless groups were found that defined the dominant physics in each system. These dimensionless numbers were then validated experimentally and numerically over a range of device parameters. Subsequently, operation criteria were developed to ensure that the reference electrode remains stable and uncontaminated. By creating a stable reference electrode on chip, any homogeneous electrochemical system that was previously studied on the macro scale can now be studied continuously in a microfluidic device. A secondary portion of this work investigates the role of surface charge with respect to electrodynamics in a microchannel. As the surface area to volume ratio increases, the concentration of charge at a channel wall may begin to approach the electrolyte concentration in the bulk solution. This phenomenon is studied numerically, with and without convection, in particular as it relates to a possible mechanism for overlimiting current. Additionally, a potential de-ionization device is theorized based on this mechanism along with scaling arguments that can be used to aid device design.
by EthelMae Victoria Dydek.
Ph.D.
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Dann, Thomas. "Pioneering investigations into organometallic electrochemistry." Thesis, University of East Anglia, 2014. https://ueaeprints.uea.ac.uk/49707/.
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Recently there has been a large effort to take advantage of electrochemistry to develop and understand novel chemical processes and reactivity. This thesis contains investigations into the synthesis and electrochemical properties of three diverse organometallic systems. In chapter 2, the first experimental determination of a an unsupported AuII-AuII bond is reported. The electrochemical characterisation of gold(III) hydride, hydroxide and chloride pincer complexes based on a backbone of a doubly cyclometalated 2,6-bis(4’-tert-butylphenyl) pyridine ligand was performed, in which it was determined that upon reduction of the AuIII complexes, an unsupported AuII dimer is formed, confirmed by characterisation of an authentic sample of the dimer. Using digital simulation, the reduction potentials of the hydride and hydroxide along with the oxidation potential of the dimer were determined, allowing the construction of a Hess cycle, from which the bond energy of the gold-gold bond in the dimer and the difference of the Au-OH and Au-H bond energies could be estimated. In chapter 3, the redox non-innocent behaviour of the ligands in zinc(II) bis(formazanate) complexes is investigated. These complexes have been electrochemically characterised by cyclic voltammetry, showing remarkably facile reduction to a radical anion, and further reduction to a dianion. Simulation of the cyclic voltammetry recorded for these compounds yielded optimised values of formal potentials, E0, and electron transfer rate constants, k0. In chapter 4, the synthesis and electrochemical characterisation of the first known examples of triazole-substituted cymantrene and cyrhetrene complexes are reported. The compounds h5-(-phenyltriazol-1-yl)cyclopentadienyl tricarbonyl manganese(I), with a phenyl, 3-aminophenyl or 4-aminophenyl substituent on the 4-position of the triazole ring were prepared via the copper(I)-catalyzed azide-alkyne cycloaddition (1,3-CuAAC) reaction. Cyclic voltammetric characterization of the redox behavior of each of the three cymantrene–triazole complexes is presented together with digital simulations, in-situ infrared spectroelectrochemistry, and DFT calculations to extract the associated kinetic and thermodynamic parameters. The synthesis and characterisation of the rhenium(I) analogues of the phenyl and 4-amino triazole substituted complexes are also reported. In chapter 5, the use of diazirines as carbene precursors for carbon surface modification is investigated, via the synthesis and characterisation of diazirine derivatised cymantrene and cyrhetrene. The surface modification of glassy carbon electrodes was attempted via irradiation of the half-sandwhich diazirine bearing complexes, resulting in oxidation waves visible on the electrode by cyclic voltammetric analysis.
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Sheng, Tian. "Heterogeneous catalytic reactions in electrochemistry." Thesis, Queen's University Belfast, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.675473.
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Cutress, Ian James. "Algorithm development in computational electrochemistry." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:a1cfb510-3656-4396-84b3-8e67b88d3d2f.
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This thesis presents algorithm development in computational chemistry, and applies new computer science concepts to voltammetric simulation. To begin, this thesis discusses why algorithm development is necessary, and inherent problems found in commercial simulation solvers. As a result of this discussion, this thesis describes the need for simulators to keep abreast of recent computational developments. Algorithm development in this thesis is taken through stages. Chapter 3 applies known theory relating to the stripping voltammetry at a macroelectrode to the diffusional model of a microdisk, using finite difference and alternating direction implicit simulation techniques. Chapter 4 introduces the concept of parallel computing, and how computational hardware has developed recently to take advantage of out-of-order calculations, by processing them in parallel to reduce simulation time. The novel area of graphics card simulation for highly parallel algorithms is also explained in detail. Chapter 5 discusses the adaptation of voltammetric finite difference algorithms to a purely parallel format for simulation by explicit solution. Through explicit solution, finite difference algorithms are applied to electrode geometries which necessitate a three-dimensional solution – elliptical electrodes; square, rectangular, and microband electrodes; and dual microdisk electrodes in collector-generator mode. Chapter 6 introduces 'Random Walk' simulations, whereby individual particles in the simulation are modelled and their trajectories over time are calculated. The random walk technique in this thesis is improved for pure three-dimensional diffusion, and adapted to graphics cards, allowing up to a factor 4000 increase in speed over previous computational methods. This method is adapted to various systems of low concentration confined voltammetry (chapter 6.4) and single molecule detection, ultra low concentration cyclic voltammetry (chapter 6.5), and underpotential deposition of thallium on mobile silver nanoparticles (chapter 6.6). Overall, this thesis presents, and applies, a series of algorithm development concepts in computational electrochemistry.
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Zhou, Xiaofei. "The electrochemistry of organic nanoparticles." Thesis, University of Oxford, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728824.
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Lin, Shioujenq Andrew. "The electrochemistry of carbon monoxide." Case Western Reserve University School of Graduate Studies / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=case1055944045.
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Howarth, Paul. "The electrochemistry of electrochemical machining." Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/10966.
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Electrochemical machining is a process that has the potential to machine complex shapes at high production rates. However, the expansion of ECM in industry has been impeded by the iterative trial and error approach that is often required to generate process parameters for any one machining set-up. This arises due to the incompleteness of models used to describe the complex physical, chemical and hydrodynamic parameter interdependencies. Such interdependence results in non-ideal effects that distort the transfer geometry between the tool shape and the required workpiece shape. The aim of this thesis is to address some of these problems, working towards developing a predictive stoichiometric model for the chemical interdependencies of ECM that can be applied to advanced alloys and therefore further the use of ECM in industry. This has been achieved by extending the planar tool system to a segmented tool arrangement capable of measuring the chemical parameters (dissolution valencies, n, and overpotentials, V0) along the flow path length. In addition, electrolyte sampling tubes have also been incorporated into this arrangement enabling the electrolyte to be sampled along the flow path length to determine the conductivity, K and the pH. This system has been applied to the stainless steel group of alloys. A systematic study of a variety of stainless steels [SS3 16, SS4 10, Jethete (J), Duplex (D) and Super Duplex (SD)] has been performed, measuring their electrochemical machining (ECM) characteristics in chloride and nitrate electrolytes. Theoretical current-time analysis using the segmented tool was used to determine the dissolution valency, n, and overpotential, V0, along the flow path length. Electrolyte samples from the interelectrode gap, taken at intervals along the flow path, and the bulk were analysed for conductivity, pH and the soluble products characterised by visible absorption spectroscopy. The insoluble products were analysed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The results indicate that the ECM dissolution characteristics of stainless steels are controlled by the surface oxide structure, which is primarily determined by the chromium content of the steel. An interesting "runaway current" phenomena was observed when machining J with nitrate electrolyte where dissolution valencies of n = 9 were observed. This phenomenon was also observed when machining pure iron. The effect was found to be caused by a short circuit reaction occurring in the interelectrode gap resulting in inefficient ECM. This short circuit problem was stopped either by using a chloride/nitrate mixed electrolyte or by the addition of a complexing agent such as EDTA. Therefore, an understanding of the dissolution chemistry has proved vital to the successful application of ECM to industrially important modern alloys.
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Udit, Andrew K. Barton Jacqueline K. "P450 BM3 electrochemistry and electrocatalysis /." Diss., Pasadena, Calif. : California Institute of Technology, 2005. http://resolver.caltech.edu/CaltechETD:etd-05112005-100825.
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Sebantu, Lambert. "Electrochemistry of polyaniline-DNA system." [Johnson City, Tenn. : East Tennessee State University], 2004. https://dc.etsu.edu/etd/895.
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Thesis (M.S.)--East Tennessee State University, 2004.Title from electronic submission form. ETSU ETD database URN: etd-0331104-130134. Includes bibliographical references. Also available via Internet at the UMI web site.
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Arnaboldi, S. "CHIRAL ELECTROCHEMISTRY IN IONIC LIQUIDS." Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/244316.
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This thesis has been initially conceived as a study of molecular electrochemistry and electrocatalysis in ionic liquids, emerging media for safe and environmentally friendly chemical and electrochemical processes, particularly focusing on the combined effects of the ionic liquid molecular structure and the nature of the electrode surface, and considering two model processes:
• the electroreductive cleavage of the carbon-halogen bond in organic halides, of high interest in the synthetic, analytical and environmental fields;
• the electrooxidative coupling of thiophene-based monomers, resulting in electrodeposition of conducting films for applications in photovoltaic, optoelectronic and sensor devices.
Both processes are thus of great applicative interest and, at the same time, two convenient model cases for electron transfer studies in ionic liquids, one reductive (via radical anion) and one oxidative (via radical cation), on which the cation and the anion of the ionic liquid should be more determining, respectively.
However, the 3-year research results actually went well beyond these initial targets, with the discovery of the outstanding properties of inherently chiral electroactive thiophene-based oligomers, on which we then concentrated most of our efforts.
In particular:
• electrooligomerization in ionic liquids of "inherently chiral" thiophene-based monomers developed by Professor Sannicolò's partner group afforded the preparation of enantiopure chiral electrodes of new concept and unprecedented enantiodiscrimination ability, resulting for the first time in a neat separation of voltammetry peaks for the enantiomers of a series of different chiral probes, also of pharmaceutical interest, in different media and operating conditions;
• such inherently chiral electroactive oligomers turned out to be mostly cyclic, idealizing chiral conducting polymers without ends, and displaying a pool of extraordinary properties, both as racemates (promising performance in organic solar cells, photoactivity, electrochromism, possibility to complex other semiconductors, outstanding oligomerization ability...) and as enantiopure antipodes (chirality tunable with electric potential, unprecedented enantiodiscrimination ability as electrodes, circularly polarized luminescence, possibility of preparation as self-supported membranes...). Such properties prompted a patent application for the new molecule class.
Furthermore, having verified the general validity and effectiveness of the inherent chirality concept, and considering our concern for ionic liquid media, we have started, again in cooperation with Professor Sannicolò's group, a further research line, aimed to the implementation of inherent chirality in new-concept ionic liquids, with the target of obtaining new, attractive media for chemical and electrochemical processes, possibly of cheap and simple synthesis, affording safe, mild and environmentally friendly operating conditions, intrinsic to the ionic liquid class, combined with powerful chirality manifestations. Three approaches, all based on the implementation of inherent chirality in the ionic liquid cation, are being developed and compared. As a valuable ancillary research product, a very simple "Egg of Columbus" protocol has been developed, providing an effective solution to the important issue of halide impurity removal from ionic liquid media.
Most of the present research has been supported by Fondazione Cariplo (Grants No. 2011-0417 and No. 2011-1851)
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FELIX, GISELE R. "Implantacao da tecnica potenciometrica para medidas in situ da solubilidade de oxidos em meio de sais fundidos .Eletrodos indicados de zirconia estabilizada." reponame:Repositório Institucional do IPEN, 1996. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10482.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP