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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Model-based experimental design in electrochemistry

Nguyen, H. Viet January 2018 (has links)
The following thesis applies an experimental design framework to investigate properties of electron transfer kinetics and homogeneous catalytic reactions. The approach is model-based and the classical Butler-Volmer description is chosen to describe the fundamental electrochemical reaction at a conductive interface. The methodology focuses on two significant design variables: the applied potential at the electrode and mass transport mode induced by physical arrangement. An important problem in electrochemistry is the recovery of model parameters from output current measurements. In this work, the identifiability function is proposed as a measure of correspondence between the parameters and output variable. Under diffusion-limit conditions, plain Monte Carlo optimization shows that the function is globally non-identifiable, or equivalently the correspondence is generally non-unique. However by selecting linear voltammetry as the applied potential, the primary parameters in the Butler-Volmer description are theoretically recovered from a single set of data. The result is accomplished via applications of Sobol ranking to reduce the parameter set and a sensitivity equation to inverse these parameters. The use of hydrodynamic tools for investigating electron transfer reactions is next considered. The work initially focuses on the rotating disk and its generalization - the rocking disk mechanism. A numerical framework is developed to analyze the latter, most notably the derivation of a Levich-like expression for the limiting current. The results are then used to compute corresponding identifiability functions for each of the above configurations. Potential effectiveness of each device in recovering kinetic parameters are straightforwardly evaluated by comparing the functional values. Furthermore, another hydrodynamic device - the rotating drum, which is highly suitable for viscous and resistive solvents, is theoretically analyzed. Combined with previous results, this rotating drum configuration shows promising potential as an alternative tool to traditional electrode arrangement. The final chapter illustrates the combination of modulated input signal and appro- priate mass transport regimes to express electro-catalytic effects. An AC voltammetry technique plays an important role in this approach and is discussed step-by-step from simple redox reaction to the complete EC′ catalytic mechanism. A general algorithm based on forward and inverse Fourier transform functions for extracting harmonic currents from the total current is presented. The catalytic effect is evaluated and compared for three cases: macro, micro electrodes under diffusion control condition and in micro fluidic environments. Experimental data are also included to support the simulated design results.
142

Estudio de la Corrosión de Ánodos de Plomo Utilizados en Electro Obtención de Cobre por Medio de Microscopía Electrónica de Barrido (SEM) y Microsonda (EDS)

Farías Villegas, Millaray Andrea January 2008 (has links)
Se estudió la morfología y composición química de la superficie de ánodos de Pb-Ca-Sn luego de ser sometidos a electro obtención de cobre, en una celda a escala de laboratorio. El objetivo fue determinar la morfología y composición química de la superficie de los ánodos luego de ser sometidos a distintas condiciones de densidad de corriente, temperatura y concentración de manganeso en el electrólito. Para la caracterización de la morfología y composición química de la superficie de los ánodos se utilizó un microscopio electrónico de barrido (SEM) que tenía acoplada una microsonda (EDS). Dichos equipos permiten realizar un análisis cualitativo y cuantitativo. La corrosión se cuantifica tomando la cantidad de plomo contenida en la capa superficial de óxidos sobre los ánodos. A menor intensidad de plomo del análisis EDS, corresponde a un más bajo contenido de dicho elemento en la capa de óxidos y se tendrá un ánodo con menor corrosión. Entre las variables estudiadas, densidad de corriente (250 y 1000 A/m2 ), temperatura (40 y 70°C) y concentración de manganeso (0, 20 y 100 mg/l) se encontró que la de mayor influencia en la corrosión de los ánodos es la temperatura. A menor temperatura, mayor es la corrosión que presentan los ánodos. El manganeso, según las condiciones, puede ayudar a proteger o a corroer el ánodo. La formación de compuestos amorfos de manganeso (MnOOH) en la capa de óxidos de Pb ayuda a la protección del ánodo. La corrosión se produce por la formación de permanganato, el que a su vez permite la formación de MnO2 sobre el ánodo que limita la formación de MnOOH protector. Para impedir lo último se debe evitar la formación de permanganato, lo que se consigue con un agente reductor, como por ejemplo con Fe2+ . Sin embargo, la mayor protección de los ánodos se da por una oxidación preferencial del Mn hasta Mn3+ en solución sin formación de precipitados sólidos. La temperatura y altas concentraciones de Mn protegen al ánodo, mientras que la densidad de corriente ejerce un efecto protector dispar, en general ayudando a la protección del ánodo a bajas temperaturas. El mejor resultado se obtuvo a 70°C, 1000 A/m2 y 100 mg/l de Mn en el electrólito, donde no se formó una capa de compuestos de Mn sobre el ánodo.
143

Développements de systèmes micro-nanofluidiques appliqués à la filtration et la préconcentration / Development of nanofluidic components applied to filtration and Concentration.

Aizel, Koceila 09 December 2013 (has links)
Les recherches menées au cours de cette thèse constituent une première étape de développement de méthodes expérimentales de concentration de nanoparticules à l'aide de composants micro-nanofluidiques. L'objectif principal est donc d'explorer différentes architectures de systèmes micro-nanofluidiques où l'étape de concentration est effectuée par effet d'exclusion stérique et/ou ionique sous l'application d'un champ de pression et/ou électrique. Une attention toute particulière a été portée sur les méthodes de caractérisation, comprenant notamment les méthodes de particule Tracking Micro-PIV et de microscopie par fluorescence pour mesurer la répartition en nanoparticules et quantifier les facteurs de concentration. Le premier axe concerne la concentration de nanoparticules dans des architectures de type « Bypass ». Dans le cas de la filtration stérique, une modélisation par méthode de différence finie permet de prédire l'apparition d'une zone localisée où la concentration est d'une centaine à un millier de fois plus élevée que la concentration initiale après une heure d'opération. Des composants micro-nano fluidique en silicium ont été réalisés afin de mener une étude paramétrique. En accord avec le modèle proposé, cette étude montre que le nombre de Peclet est le paramètre déterminent dans le choix du design et des conditions d'expérimentations optimums. Concernant la préconcentration par effet électrocinétique, les expérimentations ont essentiellement consisté à explorer le phénomène d'ICP (Ion Concentration Polarisation) et d'appliquer cette technique pour la concentration de nanoparticules. Enfin le type de géométries « Bypass » a été testé sous différentes conditions. Ainsi, le couplage avantageux de phénomènes électro-hydrodynamiques tel que le « streaming potentiel » permet d'ouvrir la voie à des systèmes de préconcentration à actionnements manuels, rapides et très simples d'utilisation. Le deuxième axe d'étude est quant à lui dédié à la conception et l'utilisation de configuration micro-nanofluidique plus originales. Y sont notamment étudiés des systèmes à configuration radial offrant une meilleure stabilité lors des étapes de préconcentration électrocinétiques. Sur la base des performances et limitations des différents systèmes micro-nanofluidiques réalisés, le dernier chapitre est une mise en perspective des champs d'applications potentiels, notamment pour les laboratoires sur puces. / The researches conducted during this thesis consist in a first step for the development of experimental methods applied to the concentration of nanoparticles using micro-nanofluidic devices. The main aim is to explore different system architectures where the préconcentration step are achieved using steric and/or ion exclusion under the influence of a pressure and/or electric field. A special attention is directed toward the characterization methods including Micro-Particle Image Velocimetry micro-PIV and fluorescent microscopy to measure the nanoparticles repartition and to quantify the concentration folds. The first axis deals with the preconcentration of nanoparticles within « Bypass » like architectures. Concerning the steric filtration, a theoretical model using finite element method allows to predict the rising of a located preconcentration zone where the local concentration is enhanced 1000 fold as compared to the initial concentration after 1h of concentration operation. Silicon Micro-nanofluidic devices were fabricated in order to conduct a parametric study. According to the proposed theoretical model, this study shows that the Peclet number is a key parameter to choose the optimal design and experimental conditions. Concerning the electrokinetic preconcentration, the experiments mainly consisted in exploring the ICP phenomenon (Ion Concentration Polarization) and in using this technic to preconcentrate nanoparticles. Finally the Bypass geometry was tested in many conditions. Thus, the advantageous coupling of electro-hydrodynamic phenomena such as the so called “streaming potential” opens new ways to fast, simple and manual preconcentration systems suitable for LOC applications. The second axis is dedicated to the conception and utilization of original micro-nanofluidic configurations. Will also be studied radial micro-nanofluidic devices offering better stability during electrokinetic preconcentration. On the basis of the performances and limitations inherent to each systems, the last chapter will focus on the potential applications relative to LOC.
144

The mechanism of antimicrobial action of electro-chemically activated (ECA) water and its healthcare applications

Kirkpatrick, Robin Duncan 11 June 2009 (has links)
The Electrochemical Activation (ECA) of water is introduced as a novel refinement of conventional electrochemical processes and the unique features and attributes are evaluated against the universal principles that have described the electrolytic processes to date. While the novel and patented novel reactor design retains the capacity to generate products common to conventional electrolysis, it also manipulates the properties of the reagent solutions to achieve an anomalous Oxidation-Reduction potential (ORP or REDOX) that cannot be replicated by traditional chemical and physical interventions. As a contemporary development in the field, the technology continues to undergo rigorous assessment and while not all of its theoretical aspects have been exhaustively interrogated, its undisputed biocidal efficacy has been widely established. Microbial vitality has been shown to be directly dependent upon the confluence of a diverse variety of physical and chemical environmental conditions. Fundamentally important in this regard is the electronic balance or REDOX potential of the microbial environment. The intricate balance of metabolic pathways that maintain cellular integrity underwrites the measures of irritability required for sustained viability. Aside from the direct effects of the conventional electrolysis products, overt electronic disruption of the immediate microbial environment initiates a cascade of secondary and largely independent autocidal molecular events which compromise the fundamental integrity of the microbe and leads to cell death. The distinctive capacity to impart unique physicochemical attributes to the ECA derived solutions also facilitates the characterisation of the same outside of the conventional physicochemical and gravimetric measures. These adjunct measures display a substantial relationship with the predictability of antimicrobial effect, and the direct relationship between inactivation of a defined microbial bioload and the titratable measures of REDOX capacity have been shown to describe a repeatable benchmark. The use of ultra-microscopy to investigate the impact of the ECA products on bacterial cell structures has shown this tool to have distinctive merit in the imaging and thus refined description of the consequences of exposure to biocidal solutions. The distinctive differences of the ECA solutions relative to conventional antibacterial compounds would suggest a heightened suitability for application in conditions where the efficacy of conventional biocidal compounds had been limited. Aeroslisation of the ECA solutions for the decontamination of airspaces challenged with tuberculosis pathogens revealed that despite initial success, further refinements to the application model will be required to meet the unresolved challenges. The health care benefits associated with the application of the ECA solutions in a medical environment substantiate the merits for the adoption of the technology as a complementary remedy for the management of nosocomial infections. The relative novelty of the technology in the commercial domain will raise questions regarding the potential for resistance development, and it has been proposed that the distinctive mechanism of biocidal action will not contribute to diminished bacterial susceptibility, as it does not reveal any cross- or co-resistance when assessed against multiple antibiotic resistant strains. These benefits are further reinforced by the capacity to install the technology for both onsite and on-demand availability, and being derived from natural ingredients (salt and water) the ECA solutions are regarded as safe and compatible for general in-contact use. Notwithstanding the multiple benefits that the technology may provide, further assessments into materials compatibility as well as potential by-products formation following environmental exposure are imperative before the unfettered adoption of this technology as a cost-effective, safe and reliable alternative to conventional disinfection can be promoted. / Thesis (PhD)--University of Pretoria, 2011. / Microbiology and Plant Pathology / unrestricted
145

Electro sequence analysis and sequence stratigraphy of wells EM1, E-M3 and E-AB1 within the central Bredasdorp Basin, South Africa

Levendal, Tegan Corinne January 2015 (has links)
>Magister Scientiae - MSc / The study area for this thesis focuses on the central northern part of the Bredasdorp Basin of southern offshore South Africa, where the depositional environments of wells E-M1, E-M3 and E-AB1 were inferred through electro sequence analysis and sequence stratigraphy analysis of the corresponding seismic line (E82-005). For that, the Petroleum Agency of South Africa (PASA) allowed access to the digital data which were loaded onto softwares such as PETREL and Kingdom SMT for interpretational purposes. The lithologies and sedimentary environments were inferred based on the shape of the gamma ray logs and reported core descriptions. The sequence stratigraphy of the basin comprises three main tectonic phases: Synrift phase, Transitional phase and Drift phase. Syn-rift phase, which began in the Middle Jurassic during a period of regional tectonism, consists of interbedded red claystones and discrete pebbly sandstone beds deposited in a non-marine setting. The syn-rift 1 succession is truncated by the regional Horizon ‘C’ (1At1 unconformity). The transitional phase was influenced by tectonic events, eustatic sea-level changes and thermal subsidence and characterized by repeated episodes of progradation and aggradation between 121Ma to 103Ma, from the top of the Horizon ‘C’ (1At1 unconformity) to the base of the 14At1 unconformity. Finally the drift phase was driven by thermal subsidence and marked by the Middle Albian14At1 unconformity which is associated with deep water submarine fan sandstones. During the Turonian (15At1 unconformity), highstand led to the deposition of thin organic-rich shales. In the thesis, it is concluded that the depositional environment is shallow marine, ranging from prograding marine shelf, a transgressive marine shelf and a prograding shelf edge delta environment.
146

Investigação da atividade de eletrocatalisadores nanoestruturados para a eletrooxidação de íons BH4- em eletrólito alcalino / Investigation of the catalytic activity of nanostructured electrocatalysts for BH4- ions electro-oxidation in alkaline media

Pasqualeti, Aniélli Martini 21 February 2013 (has links)
As células a combustível de borohidreto direto apresentam uma alta voltagem teórica (1,64 V) e alto número de elétrons por íon do combustível. Além disso, a utilização de eletrólitos alcalinos abre a possibilidade do uso de metais eletrocatalisadores não nobres e, por conseqüência, economicamente viáveis para aplicação prática. Entretanto, a falta de um eletrocatalisador altamente eficiente para a reação de oxidação de borohidreto limita o desempenho desses dispositivos, pois a oxidação total do borohidreto, envolvendo 8 elétrons por espécie BH4-, compete com vias paralelas de reação, com menor número de elétrons trocados por cada ânion BH4-. Recentemente, simulações e cálculos teóricos foram feitos para determinar os passos elementares da cinética da reação e, também, para guiar a confecção de eletrocatalisadores metálicos para a oxidação de borohidreto. Baseado nos resultados dos estudos teóricos, este trabalho teve como objetivo a investigação da eletrocatálise desta reação em nanopartículas, suportadas sobre pó de carbono, de metais puros, Au/C, Ag/C, Pt/C e Pd/C e em nanopartículas bimetálicas, formadas pela combinação entre estes metais. Os eletrocatalisadores foram sintetizados por métodos de redução química e/ou de impregnação e foram caracterizados por Difratometria de Raios X, Microscopia Eletrônica de Transmissão de Alta Resolução e Espectroscopia de Energia Dispersiva de Raios X. As atividades eletrocatalíticas foram medidas através de curvas de polarização usando eletrodo de disco rotatório. A hidrólise, com a consequente formação de H2, foi monitorada em função do potencial do eletrodo por meio de medidas de espectrometria de massas eletroquímica diferencial on-line. Os experimentos eletroquímicos, para os eletrocatalisadores de metais puros, mostraram maior atividade para Pd/C, o que foi atribuído à usa alta atividade para a eletro-oxidação do intermediário BH3OH-. O estudo do efeito da concentração de BH4-, de BH3OH- mostrou que os potenciais de onset tenderam a menores valores com o aumento da concentração, indicando que as correntes Faradaicas de eletro-oxidação direta do borohidreto e de hidroxiborano foram muito maiores que as correntes de oxidação e de desprendimento de H2. O aumento da carga de Pd/C no eletrodo levou a um aumento da corrente global de reação em baixos potenciais, o que se traduz em um efeito do aumento de área total. Dentre os materiais bimetálicos investigados, a combinação entre Pt2Pd/C apresentou a maior corrente Faradaica. O material de AgPd/C apresentou o menor potencial de onset de reação. Apesar dos resultados teóricos indicarem o aumento da atividade do Pd/C com a inserção de Ag, os resultados eletroquímicos e de espectrometria de massas indicaram maior atividade para o Pd/C puro e baixo efeito sinérgico entre os átomos de Ag e Pd. Isso foi associado ao baixo grau de interação entre os átomos de Ag e Pd nas composições atômicas investigadas. / The direct borohydride fuel cells (DBFC) display a high theoretical cell voltage (1.64) and a high electron number per borohydride ion. Furthermore, the DBFC also presents the advantages of alkaline fuel cells, in which it is possible to use non-noble metal electrocatalysts and, hence, it is economically feasible for practical applications. However the lack of highly efficient electrocatalysts for the borohydride oxidation reaction (BOR) limits the performance of these devices, since its total oxidation, involving the transfer of eight electrons per BH4- ion, competes with parallel reaction pathways with a lower number of exchanged electrons. Recently, theoretical calculations were applied to determine the elementary steps of the reaction kinetics and also to guide metallic electrocatalyst design for borohydride oxidation. Based on the theoretical results, this work aimed at the BOR electrocatalysis investigation on carbon supported nanoparticles, of pure metals, Au/C, Ag/C, Pt/C and Pd/C, and on bimetallic nanoparticles, composed by the combination of these metals. The electrocatalysts were synthesized by chemical and/or impregnation reduction methods, and X-Ray Diffraction, High Resolution Transmission Electron Microscopy and X-Ray Energy Dispersive Spectroscopy techniques were used for their physical characterization. The electrocatalytic activities were studied by steady state polarization curves using rotating disc electrodes. The borohydride hydrolysis, with the production of H2, was monitored in function of the electrode potential by on-line differential electrochemical mass spectrometry. The electrochemical experiments for the pure metal electrocatalysts showed higher electrocatalytic activity for Pd/C, and this was attributed to its high activity for BH3OH- electro-oxidation. The study of BH4- and BH3OH- concentration effect showed that with the increase of concentration, the onset potential shifted to lower values, indicating that the Faradaic currents of borohydride and hydroxyborane electro-oxidation were much higher than the current for the H2 evolution. The increase in the Pd/C load on the electrode led to an increase of the global current reaction at low potentials, which was associated to an increase in total surface area. Among the investigated bimetallic materials, the Pt2Pd/C electrocatalyst presented the higher Faradaic current. The Ag2Pd/C material showed the lower reaction potential onset. Although theoretical calculations pointed out to an increased activity of the Ag-modified Pd/C electrocatalysts in relation to that of pure Pd/C, the electrochemical and mass spectrometry results of this work indicated higher activity for pure Pd/C, and low synergic effect between the Ag and Pd atoms. This was associated to the low degree of interaction between Ag and Pd for the present investigated atomic composition.
147

The “Avant-pop” Style of Jacob Ter Veldhuis: Annotated Bibliography of Boombox Pieces with an Analysis of “Pimpin’” for Baritone Saxophone and Boombox

Roberts, Sarah L. 08 1900 (has links)
JacobTV has spent over thirty years utilizing his interest in American pop culture as the muse upon which he creates his works. Sources of popular culture including commercials, television evangelists, political speeches, interviews, and urban pop songs have earned him the title of the “Andy Warhol of new music.” His contributions to classical music are significant and include works for solo instruments and voice, chamber ensembles, and large ensembles. This study serves as an annotated bibliography of selected pieces written for saxophone and boombox written by JacobTV. Chapter 2 provides a brief historical background of electronic music and chapter 3 describes JacobTV’s compositional style and vocabulary. The pieces included in the bibliography of chapter 4 are Believer (2006) for baritone saxophone and soundtrack; Billie (2003) for alto saxophone and soundtrack; Buku (2006) for alto saxophone and soundtrack; Garden of Love (2002) for soprano saxophone and soundtrack; Grab It! (1999) for tenor saxophone and soundtrack; May This Bliss Never End (1996) for tenor saxophone, piano, and soundtrack; TaTaTa (1998) for tenor and baritone saxophone and soundtrack; Heartbreakers (1997-98) for saxophone quartet, soundtrack, and video; Jesus Is Coming (2003) for saxophone quartet and soundtrack; Pitch Black (1998) for saxophone quartet and soundtrack; and Take A Wild Guess (2007) for saxophone quartet and soundtrack. In addition, chapter 5 provides a detailed analysis of JacobTV’s composition Pimpin’ and offers further insight into his “avant-pop” compositional style.
148

Development of Electro-Microbial Carbon Capture and Conversion Systems

Al Rowaihi, Israa 05 1900 (has links)
Carbon dioxide is a viable resource, if used as a raw material for bioprocessing. It is abundant and can be collected as a byproduct from industrial processes. Globally, photosynthetic organisms utilize around 6’000 TW (terawatt) of solar energy to fix ca. 800 Gt (gigaton) of CO2 in the planets largest carbon-capture process. Photosynthesis combines light harvesting, charge separation, catalytic water splitting, generation of reduction equivalents (NADH), energy (ATP) production and CO2 fixation into one highly interconnected and regulated process. While this simplicity makes photosynthetic production of commodity interesting, yet photosynthesis suffers from low energy efficiency, which translates in an extensive footprint for solar biofuels production conditions that store < 2% of solar energy. Electron transfer processes form the core of photosynthesis. At moderate light intensity, the electron transport chains reach maximum transfer rates and only work when photons are at appropriate wavelengths, rendering the process susceptible to oxidative damage, which leads to photo-inhibition and loss of efficiency. Based on our fundamental analysis of the specialized tasks in photosynthesis, we aimed to optimize the efficiency of these processes separately, then combine them in an artificial photosynthesis (AP) process that surpasses the low efficiency of natural photosynthesis. Therefore, by combining photovoltaic light harvesting with electrolytic water splitting or CO2 reduction in combination with microbiological conversion of electrochemical products to higher valuable compounds, we developed an electro-microbial carbon capture and conversion setups that capture CO2 into the targeted bioplastic; polyhydroxybutyrate (PHB). Based on the type of the electrochemical products, and the microorganism that either (i) convert products formed by electrochemical reduction of CO2, e.g. formate (using inorganic cathodes), or (ii) use electrochemically produced H2 to reduce CO2 into higher compounds (autotrophy), three AP setups were designed: one-pot, two-pot, and three-pot setups. We evaluated the kinetic (microbial uptake and conversion, electrochemical reduction) and thermodynamics (efficiencies) of the separate processes, and the overall process efficiency of AP compared to photosynthesis. We address the influence of several parameters on efficiencies and time-space yields, e.g. salinity, pH, electrodes, media, partial pressures of H2 and CO2. These data provide a valuable basis to establish a highly efficient and continuous AP process in the future.
149

Electro-Mechanical Coupling of Indium Tin Oxide Coated Polyethylene Terephthalate ITO/PET for Flexible Solar Cells

Saleh, Mohamed A. 15 May 2013 (has links)
Indium tin oxide (ITO) is the most widely used transparent electrode in flexible solar cells because of its high transparency and conductivity. But still, cracking of ITO on PET substrates due to tensile loading is not fully understood and it affects the functionality of the solar cell tremendously as ITO loses its conductivity. Here, we investigate the cracking evolution in ITO/PET exposed to two categories of tests. Monotonous tensile testing is done in order to trace the crack propagation in ITO coating as well as determining a loading range to focus on during our study. Five cycles test is also conducted to check the crack closure effect on the resistance variation of ITO. Analytical model for the damage in ITO layer is implemented using the homogenization concept as in laminated composites for transverse cracking. The homogenization technique is done twice on COMSOL to determine the mechanical and electrical degradation of ITO due to applied loading. Finally, this damage evolution is used for a simulation to predict the degradation of ITO as function in the applied load and correlate this degradation with the resistance variation. Experimental results showed that during unloading, crack closure results in recovery of conductivity and decrease in the overall resistance of the cracked ITO. Also, statistics about the crack spacing showed that the cracking pattern is not perfectly periodical however it has a positively skewed distribution. The higher the applied load, the less the discrepancy in the crack spacing data. It was found that the cracking mechanism of ITO starts with transverse cracking with local delamination at the crack tip unlike the mechanism proposed in the literature of having only cracking pattern without any local delamination. This is the actual mechanism that leads to the high increase in ITO resistance. The analytical code simulates the damage evolution in the ITO layer as function in the applied strain. This will be extended further to correlate the damage to the resistance variation in following studies.
150

Surface and Interface Engineering of Conjugated Polymers and Nanomaterials in Applications of Supercapacitors and Surface-functionalization

Hou, Yuanfang 23 May 2016 (has links)
In this dissertation, three aspects about surface and interface engineering of conjugated polymers and nanomaterials will be discussed. (i) There is a significant promise for electroactive conjugated polymers (ECPs) in applications of electrochemical devices including energy harvesting, electrochromic displays, etc. Among these, ECPs has also been developed as electroactive materials in electrochemical supercapacitors (ESCs). Compared with metal oxides, ECPs are attractive because they have good intrinsic conductivity, low band-gaps, relatively fast doping-and-undoping process, the ease of synthesis, and tunable electronic and structural properties through structural modifications. Here, Multiple-branch-chain 3,4-ethylenedioxythiophene (EDOT) derivatives was designed as crosslinkers in the co-electropolymerization of EDOT to optimize its morphology and improve the cycling stability of PEDOT in the supercapacitor applications. High-surface-area π-conjugated polymeric networks can be synthesized via the electrochemical copolymerization of the 2D (trivalent) motifs benzo[1,2-b:3,4-b’:5,6-b’’]trithiophene (BTT) and tris-EDOT-benzo[1,2-b:3,4-b’:5,6-b’’]trithiophene (TEBTT) with EDOT. Of all the material systems studied, P(TEBTT/EDOT)-based frameworks achieved the highest areal capacitance with values as high as 443.8 mF cm-2 (at 1 mA cm-2), higher than those achieved by the respective homopolymers (PTEBTT and PEDOT) in the same experimental conditions of electrodeposition (PTEBTT: 271.1 mF cm-2 (at 1 mA cm-2); PEDOT: 12.1 mF cm-2 (at 1 mA cm-2). (ii) In electrochemical process, the suitable choice of appropriate electrolytes to enlarge the safe working potential window with electrolyte stability is well known to improve ECPs’ performance in ESCs applications. Ionic liquids (ILs) are ion-composed salts and usually fluid within a wide temperature range with low melting points. There are many unique characteristics for these intrinsic ion conductors, including high ionic conductivity, wide electrochemical voltage windows in neutral conditions, fast ion mobility in redox reaction process (>10-14 m2 V-1 s-1), low vapor pressure, and environmental stability. These properties qualified ambient-temperature ILs to be applied as supporting medium for various devices and materials processing applications in both industry and academia, overcoming the limitation of volatile organic compounds (VOCs). Especially, ILs have been utilized as superior medium to electrodeposit metals, alloys, semiconductors and ECPs in the application of supercapacitors. Electropolymerization of EDOT and its derivative 4,4'-dimethoxy-3,3'-bithiophene (BEDOT) have been studied in three kinds of imidazolium-based ionic liquids and conducting salt in VOCs with different anions both as the growth medium and the supporting electrolyte, to assess the influence of these anions on their morphology and electrochemical activity. It is found these thiophene polymers grown in ILs with higher viscosity and lower diffusion shows much slower growth rate and orderly morphologies than in Tetrabutylammonium hexafluorophosphate (TBAPF6) dissolved in acetonitrile (ACN), and gives better electrochemical performance via cyclic voltammetry (CV) and galvanostatic charge-and-discharge (CD) studies. Polymers displayed multiple redox peaks in several cases, the possible reasons and origins are discussed. The synthesized polymer can be affected greatly by both the ILs with different anion/cation, and its mutal interation with targeted monomer.. As far as known, there is no systematic study on how the anions of ILs and common organic solution could play a role as a medium both for polymerization and post-polymerization electrolyte for PEDOT and its derivatives. This study can be used as an easy reference and provide experimental diagnositc data when selecting ionic liquids to investigate and optimize thiophene-based electrochemical systems, such as batteries and supercapactiors. (iii) Another aspect about interface chemistry of direct functionalization of nanodiamond with maleimide has also been addressed. Functional nanodiamonds are promising candidates for extensive practical applications in surface science, photonics and nanomedicine. Here, a protocol of direct functionalization is described by which maleimide-derivatized substituents can be appended to the outer shell of thermally annealed nanodiamonds through Diels-Alder reaction. This protocol can be carried out in room temperature, ambient atmosphere, without catalyst, and provide functionalized nanodiamonds with good solubility in organic solution. Also, this method can be applied for other maleimide derivatives,e.g.m aleimide-fluorescene, which can be applied in fluorescence labeling, sensing, and drug delivery. A series of techniques, especially Fourier transform infrared spectroscopy (FTIR), and Solid State Nuclear Magnetic Resonance (SS-NMR) was conducted for the analysis of surface chemistry and the investigation of the two-point binding strategy in details.

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