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Reuter, Daniel [Verfasser], et Alois [Akademischer Betreuer] Loidl. « Ionic and Dipolar Dynamics in Glassy Electrolytes / Daniel Reuter ; Betreuer : Alois Loidl ». Augsburg : Universität Augsburg, 2020. http://d-nb.info/1222437201/34.
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Karlsson, Christian. « Ionic conduction in glasses and nanocomposite polymer electrolytes / ». Göteborg : Chalmers university of technology, 2003. http://catalogue.bnf.fr/ark:/12148/cb392991306.
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Salami, Taiye James. « Novel Conductive Glass-Perovskites as Solid Electrolytes in Lithium – ion Batteries ». University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1533220964477566.
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Novita, Deassy I. « Evidence for Intermediate Phase in Solid Electrolyte Glasses ». University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1234751813.
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Mahapatra, Manoj Kumar. « Study of Seal Glass for Solid Oxide Fuel/Electrolyzer Cells ». Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/77281.
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Seal glass is essential and plays a crucial role in solid oxide fuel/electrolyzer cell performance and durability. A seal glass should have a combination of thermal, chemical, mechanical, and electrical properties in order to seal different cell components and stacks and prevent gas leakage. All the desired properties can simultaneously be obtained in a seal glass by suitable compositional design. In this dissertation, SrO-La₂O₃-A₂O₃-B₂O₃3-SiO₂ based seal glasses have been developed and composition-structure-property relationships have been investigated. B₂O₃ free SrO-La₂O₃-Al₂O₃-SiO₂ based seal glass is the most suitable and its compatibility with the metallic interconnects and sealing performances have been evaluated.
A seal glass should be stable for 5,000-40,000 hrs in the oxidizing and reducing atmospheres at 600-900°C but both the thermal and chemical stability is a persistent problem. The effect of Al₂O₃ on a SrO-La₂O₃-Al₂O₃-B₂O₃-SiO₂ based seal glass has been studied to improve the thermal properties, such as glass transition temperature, softening temperature and thermal expansion coefficient, and the thermal stability. Al₂O₃ improves the thermal stability but does not significantly affect the thermal properties of the seal glass.
Comprehensive understanding of composition-structure-property relationships is needed to design a suitable seal glass. The thermal properties and stability of a borosilicate seal glass depend on the B2O3:SiO2 ratio in the composition. The role of B₂O₃:SiO₂ ratio on the glass network structure of the SrO-La₂O₃-Al₂O₃-B₂O₃-SiO₂ based seal glasses has been studied using Raman spectroscopy and nuclear magneto resonance spectroscopy. The thermal properties and thermal stability were correlated with the glass network structure and the calculated network connectivity. This study shows that the thermal properties degrade with increasing B₂O₃:SiO₂ ratio due to increase in the non-bridging oxygen and decrease in the network connectivity. High B₂O₃:SiO₂ ratio induces BO4 and SiO4 structural unit ordering, increases micro-heterogeneity, and subsequently degrades thermal stability. B₂O₃ free SrO-La₂O₃-Al₂O₃-SiO₂ seal glass shows the best combination of the thermal properties and thermal stability among the studied glasses.
Nickel or nickel oxide is added into a seal glass to modify the thermal properties depending on the specific composition. The role of nickel as a network former or modifier and its effect on the thermal properties and thermal stability of the SrO-La₂O₃-Al₂O₃-SiO₂ based seal glasses have been investigated. Nickel is a modifier in this glass system and does not improve the thermal properties but degrades thermal stability by decreasing network connectivity and inducing micro-heterogeneity.
The interconnect-seal glass interface stability is the most crucial for solid oxide fuel/electrolyzer cell. Crofer 22 APU and AISI 441 alloys are the preferred interconnects. The interfacial stability of the SrO-La₂O₃-Al₂O₃-SiO₂ based seal glass with these alloys have been studied as a function of time (0-1000 hrs), temperature (700-850°C), atmospheres (air, argon, and H₂O/H₂) using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction analysis (XRD). Complementary analytical techniques such as wave length dispersive spectroscopy (WDS) and SEM of thin samples were also carried out for selected samples. This study shows good interfacial stability of the SrO-La₂O₃-Al₂O₃-SiO₂ based seal glass with these alloys for the studied conditions.
A suitable seal glass should be hermetic and withstand 100-1000 thermal cycles for practical application. Sealing performances of the SrO-La2O3-Al2O3-SiO2 based seal glass have been evaluated by pressure-leakage method. The seal glass is hermetic for at least 2000 hrs and withstands 100 thermal cycles. Overall, present work shows that the SrO-La₂O₃-Al₂O₃-SiO₂ based glass has all the desired properties and suitable for solid oxide fuel/electrolyzer cell seal.Ph. D.
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Cohen, Sally Elizabeth. « Synthesis and characterisation of glass electrolytes for sensing bismuth and antimony in non ferrous metals ». Thesis, University of Leeds, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275676.
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Wachtman, Jacob L. « Molecular structure of (AsSe)₁₋x̳ (Ag₂Se)x̳ solid electrolyte glasses ». Cincinnati, Ohio : University of Cincinnati, 2009. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1250625212.
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Thesis (M.S.)--University of Cincinnati, 2009.On t.p. "x̳" is subscript. Advisor: P. Boolchand. Title from electronic thesis title page (viewed Jan. 14, 2010). Includes abstract. Keywords: AsSe; Ag2Se; AgAsSe; solid electrolyte glass; raman. Includes bibliographical references.
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Pablo, Fleurdelis, of Western Sydney Nepean University et Faculty of Science and Technology. « Adsorptive stripping voltammetry of trace elements on a glassy carbon mercury film electrode ». THESIS_FST_XXX_Pablo_F.xml, 1994. http://handle.uws.edu.au:8081/1959.7/207.
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This thesis describes the development of new adsorptive cathodic stripping voltammetric methods for reliable determination of some trace metals in biological and environmental materials on a glassy carbon mercury film electrode. In particular, the development of these methods involved selection of a suitable complexing agent for the respective metal ion studied, characterization of the electrode processes, investigation of factors affecting the voltammetric response such as concentration and pH of supporting electrolyte, concentration of complexing agent, accumulation potential, accumulation time and electrode rotation rate. Also, organic and inorganic interferences, linear concentration range, and detection limits were carefully considered. Furthermore, the analytical application of the method was demonstrated for each metal in biological and/or environmental materials, after optimization of the sample decomposition procedure. Some conclusions : the results obtained by the AdCSV method for the determination of tin in juices agreed reasonably with those obtained by atomic absorption method; the use of the adsorptive voltammetric technique after dry-ashing and UV treatment of the samples was successfully demonstrated for the determination of vanadium in standard reference materials such as urban particulate matter, peach leaves, apple leaves and bovine liver; and, the use of the adsorptive stripping voltammetric technique, after decomposition of samples by dry-ashing and UV treatment, was successfully demonstrated for the determination of molybdenum in peach leaves, apple leaves and bovine liver samples.Doctor of Philosophy (PhD)
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Jui, Sumit Kumar Narendrakumar. « Study of Micro-Electrochemical Discharge Machining (ECDM) Using Low Electrolyte Concentration ». University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1384870046.
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Castro, Alexandre. « Développement de batteries tout solide sodium ion à base d’électrolyte en verre de chalcogénures ». Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S126/document.
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L'évolution des consommations énergétiques au cours des dernières décennies entraîne des modifications majeures dans la conception des systèmes électriques autonomes à fournir, que ce soit pour des applications électriques ou électroniques. La nécessité présente de réaliser des générateurs capables de délivrer l'énergie suffisante, avec une garantie de sûreté maximale, impose à la recherche l'exploration de nouvelles voies de stockage. Les voies actuelles par accumulateurs au lithium tendent à montrer leurs limites, tant stratégiques qu'environnementales. Dans ce cadre, la construction de nouveaux systèmes électrochimiques mettant en œuvre le sodium ouvre une possibilité de réalisation d'accumulateurs sans lithium. Le besoin de batteries toujours plus performantes oblige à des conceptions innovantes, abandonnant la voie liquide au profit de systèmes tout solide plus sécuritaires. De plus, la miniaturisation de l'électronique conduit à revoir le dimensionnement des batteries, vers des batteries de type micro, pour lesquelles l'intérêt d'un empilement tout solide n'est plus à démontrer. Aujourd'hui, des verres de chalcogénures au soufre permettent l'accès à des conductivités ioniques qui laissent entrevoir la possibilité d'une réalisation de batteries tout solide, à la fois sous forme de micro batteries ou de batteries massives. Un effort de recherche a été porté à la formulation de ces verres de chalcogénures afin d'obtenir des conductivités ioniques maximales et des propriétés autorisant leur utilisation comme électrolyte. La modification de ces verres met alors en lumière l'intérêt des différents éléments les composant. L'étude de la mise en forme de l'électrolyte par dépôts de type couches minces (obtenues par Radio Fréquence Magnétron Sputering, RFMS) prouve la faisabilité de ces micro batteries tout solide au sodium. Par la suite, la réalisation de batteries massives tout solide a demandé la synthèse de deux matériaux de cathode (NaCrO2 et Na[Ni0,25Fe0,5Mn0,25]O2) et de deux matériaux d'anode (Na15Sn4 et Na) permettant ainsi la mise en œuvre de quatre empilements électrochimiques, tous caractérisés comme accumulateurs. Enfin, l'amélioration des interfaces grâce à un gel-polymère a permis de perfectionner les propriétés des assemblages avec notamment une augmentation des vitesses de charge/décharge et une mobilisation accrue des matériaux actifs de cathodeThe evolution of energy consumption in recent decades has led to major changes in the design of autonomous electrical systems dedicated to either electrical or electronic applications. The present demand to build generators capable of delivering sufficient energy, with a guarantee of maximum safety, requires to explore new storage routes. The current lithium battery routes tend to show their limits, both strategic and environmental. In this context, the construction of new electrochemical systems implementing sodium opens the way of the lithium-free accumulators production. The need for ever more efficient batteries requires innovative designs, giving up the liquid path in favor of stronger solid systems. In addition, the miniaturization of electronics leads to a review of the size of the batteries, to micro-type batteries, for which the interest of a solid stack is no longer to demonstrate. Today, sulfur chalcogenide glasses allow access to ionic conductivities that suggest the possibility of a realization of all solid batteries, both in the form of micro batteries or massive batteries. A research effort has been made to formulate these chalcogenide glasses in order to obtain a maximum of ionic conductivity and properties allowing their use as electrolytes. The composition of these glasses highlights the interest of the different elements for such properties. The study of the electrolyte shaping by thin-film deposition (obtained by Radio Frequency Magnetron Sputering, RFMS) proves the feasibility of these all-solid sodium micro-batteries. Subsequently, the realization of massive all solid batteries required the synthesis of two cathode materials (NaCrO2 and Na [Ni0.25Fe0.5Mn0.25]O2) and two anode materials (Na15Sn4 and Na) thus allowing the implementation of four electrochemical stacks, all characterized as accumulators. Finally, the improvement of the interfaces thanks to a gel-polymer made it possible to improve the properties of the assemblies with notably an increase of the speeds of charge / discharge and an enhanced mobilization of the cathode active materials
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Wachtman, Jacob L. « Molecular Structure of (AsSe)1-x(Ag2Se)x solid electrolyte glasses ». University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1250625212.
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Pablo, Fleurdelis. « Adsorptive stripping voltammetry of trace elements on a glassy carbon mercury film electrode ». Thesis, View thesis, 1994. http://handle.uws.edu.au:8081/1959.7/207.
Texte intégralRésumé :
This thesis describes the development of new adsorptive cathodic stripping voltammetric methods for reliable determination of some trace metals in biological and environmental materials on a glassy carbon mercury film electrode. In particular, the development of these methods involved selection of a suitable complexing agent for the respective metal ion studied, characterization of the electrode processes, investigation of factors affecting the voltammetric response such as concentration and pH of supporting electrolyte, concentration of complexing agent, accumulation potential, accumulation time and electrode rotation rate. Also, organic and inorganic interferences, linear concentration range, and detection limits were carefully considered. Furthermore, the analytical application of the method was demonstrated for each metal in biological and/or environmental materials, after optimization of the sample decomposition procedure. Some conclusions : the results obtained by the AdCSV method for the determination of tin in juices agreed reasonably with those obtained by atomic absorption method; the use of the adsorptive voltammetric technique after dry-ashing and UV treatment of the samples was successfully demonstrated for the determination of vanadium in standard reference materials such as urban particulate matter, peach leaves, apple leaves and bovine liver; and, the use of the adsorptive stripping voltammetric technique, after decomposition of samples by dry-ashing and UV treatment, was successfully demonstrated for the determination of molybdenum in peach leaves, apple leaves and bovine liver samples.
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Chamaani, Amir. « Hybrid Polymer Electrolyte for Lithium-Oxygen Battery Application ». FIU Digital Commons, 2017. https://digitalcommons.fiu.edu/etd/3562.
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The transition from fossil fuels to renewable resources has created more demand for energy storage devices. Lithium-oxygen (Li-O2) batteries have attracted much attention due to their high theoretical energy densities. They, however, are still in their infancy and several fundamental challenges remain to be addressed. Advanced analytical techniques have revealed that all components of a Li-O2 battery undergo undesirable degradation during discharge/charge cycling, contributing to reduced cyclability. Despite many attempts to minimize the anode and cathode degradation, the electrolyte remains as the leading cause for rapid capacity fading and poor cyclability in Li-O2 batteries. In this dissertation, composite gel polymer electrolytes (cGPEs) consisting of a UV-curable polymer, tetragylme based electrolyte, and glass microfibers with a diameter of ~1 µm and an aspect ratio of >100 have been developed for their use in Li-O2 battery application. The Li-O2 batteries containing cGPEs showed superior charge/discharge cycling for 500 mAh.g-1 cycle capacity with as high as 400% increase in cycles for cGPE over gel polymer electrolytes (GPEs). Results using in-situ electrochemical impedance spectroscopy (EIS), Raman spectroscopy, and scanning electron microscopy revealed that the source of the improvement was the reduction of the rate of lithium carbonates formation on the surface of the cathode. This decrease in formation rate afforded by cGPE-containing batteries was possible due to the decrease of the rate of electrolyte decomposition. The increase in solvated to the paired Li+ ratio at the cathode, afforded by increased lithium transference number, helped lessen the probability of superoxide radicals reacting with the tetraglyme solvent. This stabilization during cycling helped prolong the cycling life of the batteries. The effect of ion complexes on the stability of liquid glyme based electrolytes with various lithium salt concentrations has also been investigated for Li-O2 batteries. Charge/discharge cycling with a cycle capacity of 500 mAh·g-1 showed an improvement as high as 300% for electrolytes containing higher lithium salt concentrations. Analysis of the Raman spectroscopy data of the electrolytes suggested that the increase in lithium salt concentration afforded the formation of cation-solvent complexes, which in turn, mitigated the tetragylme degradation.
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JAVED, HASSAN. « Design, synthesis and characterization of glass-ceramic and ceramic based materials for solid oxide electrolysis cell (SOEC) applications ». Doctoral thesis, Politecnico di Torino, 2019. http://hdl.handle.net/11583/2743336.
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Matinise, Nolubabalo. « Electrolytic determination of phthalates organic pollutants with n nostructured titanium and iron oxides sensors ». Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_1177_1305892404.
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This work reports the chemical synthesis, characterisation and electrochemical application of titanium dioxide (TiO2) and iron oxide (Fe2O3) nanoparticles in the determination of phthalates. The other part of this work involved electrochemical polymerization of aniline doped with titanium and iron oxide nanoparticles for the sensor platform in the electrolytic determination of phthalates. The TiO2 and Fe2O3 nanoparticles were prepared by sol gel and hydrothermal methods respectively. Particle sizes of 20 nm (TiO2) and 50 nm (Fe2O3) were estimated from transmission electron microscopy (TEM) The other technical methods used in this study for the characterization of the TiO2 and iron oxide Fe2O3 NPs were SEM, XRD and UV- visible spectroscopy. Cyclic voltammetry, square wave voltammetry and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical properties of the nanoparticles. These electrochemical studies of the nanoparticles were performed with a Fe2O3 or TiO2/nafion/glassy carbon membrane electrode in 0.1 M phosphate buffer (pH 7.0) and 0.1 M lithium perchlorate (pH 6.8) under an aerobic condition.
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Tambelli, Caio Eduardo de Campos. « Estudo por técnicas de ressonância magnética nuclear das propriedades físicas de novos eletrólitos poliméricos e vidros fosfatos ». Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-01092010-172135/.
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Neste trabalho foram estudados novos eletrólitos poliméricos e vidros fosfatos utilizando a técnica de Ressonância Magnética Nuclear. Os eletrólitos estudados foram o poliéster (etileno glicol / ácido cítrico - EG/AC) e os filmes de hidroxietilcelulose (HEC) entrecruzados com diisocianatos de poli (óxido de etileno) e poli (óxido de propileno), ambos dopados com sais de lítio No estudo dos eletrólitos poliméricos, foram realizadas medidas da forma de linha e da taxa de relaxação spin-rede do 1H e do 7Li em função da temperatura e da viscosidade, com objetivo de estudar a mobilidade da cadeia polimérica e dos íons lítio. Os valores para o tempo de correlação, obtidos dos dados de relaxação, mostram que a mobilidade da cadeia polimérica e dos íons lítio são comparáveis aos encontrados em outros eletrólitos poliméricos similares Os sistemas vítreos estudados foram o vidro fosfato In(PO3)3 e o sistema binário (1-x)In(PO3)3 - xBaF2, com o objetivo de determinar o grau de polimerização da cadeia de fosfatos. Os estudos do 31P MAS RMN para diferentes tempos de fusão dos vidros fosfatos, permitiram verificar que presença da água reduz o comprimento da cadeia pela hidrólise das ligações P-O-P produzindo duas cadeias com grupos terminais -P-OH. A adição do BaF2 no vidro fosfato, reduz o comprimento da cadeia de fosfatos formando oxigênio não ponteante. Altas concentrações do BaF2 causa a depolimerização da cadeia de fosfatos formando grupos pirofosfatos (Q1) e grupos ortofosfatos (Q0).In this work we report the study of new polymer electrolytes and phosphate glasses using Nuclear Magnetic Resonance (NMR) technique. The polymer electrolytes studied were polyester (glycol ethylene / citric acid) and films formed by hydroxyethylcelluloses (HEC), poly(ethy1ene oxide) and poly(propy1ene oxide) diisocyanates, both with lithium salt. To study the mobility of polymer chains and lithium ions in the polymer electrolytes, measurements of the temperature and viscosity dependence of 1H e do 7Li lineshape and spin-lattice relaxation rate were realized. The correlation times obtained from relaxation data, show that the mobility of polymer chains and lithium ions are comparable to those found in other similar polymer electrolytes. The degree of polymerization of the phosphate chain was studied in phosphate glass In(PO3)3 and in the binary system(1-x)In(PO3)3 - xBaF2. The 31P MAS NMR for different melting times, indicate that the water reduces the chain length by hydrolyzing P-O-P bonds to produce two separated chains, terminated by -P-OH groups. The addition of BaF2 in the phosphate glass, reduces the phosphate chain length by forming non-bridging oxygen ions. High concentration of BaF2 causes depolymerization of the phosphate chain to create pyrophosphate groups (Q1) and orthophosphate groups (Q0).
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Junior, Pedro Luiz Frare. « Estudo de condutores iônicos vítreos e poliméricos por ressonância magnética nuclear ». Universidade de São Paulo, 1996. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-13122013-101728/.
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Neste trabalho apresenta-se um estudo por Ressonância Magnética Nuclear (RMN) dos condutores iônicos vítreos (fluoroindatos) e poliméricos, com base nos Poli-Óxidos de Propileno (PPO). Nosso principal objetivo é investigar as propriedades de RMN dos íons responsáveis pela condução iônica nestes condutores amorfos. Entre as propriedades estudadas estão os mecanismos de relaxação nuclear em função da temperatura e freqüência, a forma de linha e o segundo momento associado as linhas de ressonância. No caso dos complexos poliméricos, nossos resultados indicam que a condutividade é governada pelos movimentos segmentários de cadeia polimérica. A análise do segundo momento das linhas, permitiu determinar a intensidade das interações dominantes que estão envolvidas nestes complexos. Dos resultados de relaxação em polímeros, obtivemos os parâmetros importantes do movimento iônico, tais como: a energia de ativação (Ea), a freqüência de saltos (▨ e a dependência em freqüência da taxa de relaxação. Nossos resultados refletem a natureza desordenada destes materiais e a complexidade do processo de condução iônica nestes sistemas. Nos estudos realizados em vidros fluorados, pudemos discriminar os mecanismos re relaxação spin-rede presentes. Estes resultados mostram que, abaixo da temperatura de transição vítrea (Tg), T1-1 é fracamente dependente da freqüência e da temperatura. Enquanto que acima de Tg, T1-1 passa a ter um comportamento típico de sistemas termicamente ativados. Um terceiro mecanismo (contribuição paramagnética) foi estudado nas amostras de vidros fluoroindatos dopados com um íon paramagnético (Gd3+), onde pôde se observar das medidas da taxa de relaxação spin-spin (T2-1), o comportamento descrito pela interação hiperfina de contato, entre o núcleo de 19F em difusão com o spin eletrônico do íon paramagnético. Aborda-se ainda, aspectos técnicos necessários a utilização e desenvolvimento do espectrômetro, tais como: sondas de alta e baixa temperaturas, circuitos de recepção e softwares de controleIn this work we report a Nuclear Magnetic Resonance (NMR) study of two types of ionic conductors: fluoroindates glasses and polymers based on polypropylene oxide (PPO). We have investigated the nuclear spin relaxation process of the diffusing ions by measuring relaxation times and the second moment of the resonance line as a function of temperature and frequency. In the case of the polymeric systems our results indicates that the conduction mechanism is d e d by segmental motions of the polymer chain. Analysis of the second moment allow us to determine the intensity of the main interactions involved and, from relaxation measurements, important parameters of the ionic motion can be extracted. Our results are compatible with the complexity of the ionic conduction process characteristic of these disordered systems. Studies realized with the fluoride glass systems allow us to distinguish between the different spin-lattice relaxation mechanisms. Results show that bellow the vitreous transition temperature (Tg), T1-1 has a weak dependence with temperature and frequency. The behavior of T1-1 above Tg is typical of thermally activated systems, from which we could calculate the activation energy. A third mechanism (paramagnetic contribution) was studied in the fluoride glasses doped with (Gd3+). In this case, the spin-spin relaxation process is dominated by the contact hyperfine interaction between diffusing 19F nuclei and the electronic spin of the paramagnetic ion. We still discuss in this work different technical aspects of the NMR spectrometer, such as the low and high temperature probes and software for control and data analysis
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Andrejevic, Marina. « Functionalized Sulfone and Sulfonamide Based Poly(arylene ether)s ». Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1402073837.
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He, Ruixuan. « Studies on Ionic Conductivity and Electrochemical Stability of Plasticized Photopolymerized Polymer Electrolyte Membranes for Solid State Lithium Ion Batteries ». University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1478969519588062.
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Clément, Valérie. « Réalisation d'un dispositif de mesure de l'effet Hall ionique : application au système vitreux AgPO3-AgI ». Grenoble 1, 1987. http://www.theses.fr/1987GRE10027.
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Beckert, Steffen, Frank Stallmach, Jens Kullmann et Dirk Enke. « Concentration dependent self-diffusion coefficients of aqueous electrolyte solutions in bulk phase and confined in porous glasses measured by pulsed field gradient NMR ». Diffsuion fundamentals 16 (2011) 38, S. 1-2, 2011. https://ul.qucosa.de/id/qucosa%3A13773.
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Beckert, Steffen, Frank Stallmach, Jens Kullmann et Dirk Enke. « Concentration dependent self-diffusion coefficients of aqueous electrolyte solutions in bulk phase and confined in porous glasses measured by pulsed field gradient NMR ». Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-184977.
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Fleutot, Benoit. « Amélioration des performances des microbatteries au lithium : corrélation entre la structure locale et la conductivité ionique d’électrolytes solides amorphes ». Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14162/document.
Texte intégralRésumé :
Les microbatteries sont des microsources d’énergie adaptées à l’alimentation des microsystèmes tels que l’horloge à temps réel des téléphones portables, les étiquettes intelligentes RFID…. Pour pouvoir être considéré comme un composant classique de la microélectronique, la microbatterie doit être compatible avec le processus de soudure de type solder-reflow qui atteint une température de 260 °C pendant quelques secondes. Au cours de cette thèse, nous nous sommes focalisés sur l’étude de couches minces de LiPON (oxynitrure de phosphate de lithium) utilisé comme électrolyte solide qui est le matériau limitant pour une application à basse température en établissant des relations entre sa composition, sa structure et ses performances électriques. Ayant observé une baisse des performances après traitement thermique, nous avons proposé un matériau présentant une meilleure stabilité. Nous avons également étudié la compatibilité des autres couches ainsi que l’empilement complet de la microbatterie vis-à-vis du solder-reflowMicrobatteries are energy sources well-adapted to power microsystems such as the real time clock of mobile phones, smart tags RFID. To be considered as a microelectronic component, the microbattery must be compatible with the solder-reflow process which reaches a temperature of 260 °C during few seconds. During this Ph-D, various thin films of LiPON (lithium phosphate oxynitride) used as amorphous solid electrolyte have been prepared by sputtering. As this material presents limited performances for an application of the microbattery at low temperature, we have investigated the influence of its composition and local structure on its electrical performances. In addition, a decrease of its performances has been noticed after solder-reflow. In this work, we have proposed a new material, much more thermally stable. Finally, we have studied the compatibility of other active layers as well as the all-solid-state microbattery towards the solder-reflow
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Holbrook, Chad Monroe. « Characterization and Solid Electrolyte behavior of (Ag2S)x(As2S3)1-x glasses ». University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1187051715.
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Agapov, Alexander. « Decoupling Phenomena in Dynamics of Soft Matter ». University of Akron / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=akron1321922264.
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Martins, Rodrigues Ana Candida. « Synthèse et propriétés électriques de verres oxydes conducteurs par ion lithium ». Grenoble INPG, 1988. http://www.theses.fr/1988INPG0010.
Texte intégralRésumé :
L'etude porte sur la variation de la conductivite electrique des systemes borotellurates et borophosphates suivants : lio::(2)-b::(2)o::(3)-te::(2)o::(4) et li::(2)o-b::(2)o::(3)-p::(2)o::(6)-lix (x=f, cl, br). L'effet de formateur mixte pour le premier systeme et l'effet de sel dopant dans le second systeme ont ete interpretes a l'aide de la theorie de l'electrolyte faible et d'un modele de solutions regulieres
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Cozic, Solenn. « Étude des propriétés électriques et structurales de verres de sulfures au lithium pour électrolytes de batteries tout-solide ». Thesis, Rennes 1, 2016. http://www.theses.fr/2016REN1S054/document.
Texte intégralRésumé :
Le marché du stockage de l'énergie est en perpétuelle expansion, tant pour les applications nomades que fixes. Afin de répondre aux exigences requises pour les diverses applications (appareils électroniques, véhicules hybrides et électriques, stockage des énergies renouvelables…), des batteries toujours plus performantes, compactes et légères doivent être développées. Pour cela, les batteries utilisant du lithium métallique en tant qu'anode sont les plus attractives en termes de densités d'énergies. Néanmoins, l'utilisation d'électrolytes liquides conventionnels, généralement des solvants organiques inflammables, dans de tels dispositifs soulève des problématiques de sécurité. Les travaux de recherche présentés dans ce manuscrit concernent l'étude de matériaux vitreux pouvant être utilisés en tant qu'électrolyte solide afin de permettre le développement de batteries tout-solide sûres et performantes. Des verres de sulfures au lithium, attractifs pour leurs propriétés de conduction ionique, sont étudiés et caractérisés. Les propriétés de conduction ionique dans les verres étant toujours mal comprises et sujettes à controverses, l'analyse structurale des verres présente ici un réel intérêt pour une meilleure compréhension des corrélations entre structure et propriétés. Un effort de recherche a donc été porté sur l'étude de l'ordre local dans les verres préparés via différentes techniques d'analyse structurale complémentaires. Enfin, les matériaux vitreux, sont de manière générale relativement faciles à mettre en forme. Les verres étudiés dans ce manuscrit peuvent alors également être utilisés en tant qu'électrolytes sous forme de couches minces dans les micro-batteries. Des premiers essais de dépôts par pulvérisation cathodique RF magnétron de couches minces conductrices ont donc été effectués et constituent la première brique à la fabrication de micro-batteriesThe energy storage market is in constant growth for both portable and stationary applications. To satisfy the requirements of various applications (electronic devices, hybrid-electric vehicles, renewable energy storage…), always more efficient, more compact and lightweight batteries have to be developed. Then, thanks to their high energy densities, batteries using Li metal anodes are the most promising to complete this challenge. However, the use of conventional liquid electrolytes raises safety issues, mainly related to the flammability of the organic liquid. In this thesis, glassy materials, exhibiting great interest towards developing solid electrolytes are considered and might enable the development of safe and efficient all-solid-state batteries. Here, Li-sulfide glasses, attractive for their ionic conduction properties, have been studied and characterized. The ionic conduction properties of glasses are still misunderstood and controversial, the structural investigation of glasses is of great interest in order to get a better understanding of structure-properties relationship. Then, the short and intermediate range order of prepared glasses have been investigated by the mean of various complementary structural analysis techniques. Finally, glassy materials are usually quite easy to shape. Thus, studied glasses in this thesis can also be used as thin-film electrolytes in microbatteries. First tests of sputtering of conducting thin-films have been performed by RF magnetron sputtering and constitute a first step in order to design microbatteries
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Biswas, Tanujit. « Investigation of Switching mechanism, Thermal, Electrochemical and Structural properties of Solid Electrolytic, Superionic α-AgI based Silver Molybdate glass for Resistive Memory (RRAM) Applications ». Thesis, 2019. https://etd.iisc.ac.in/handle/2005/4346.
Texte intégralRésumé :
Developing efficient, fast performing and thermally stable AgI-Ag2O-MoO3glasses are of great interest for Resistive Random Access Memory (RRAM) applications; however there many challenges such as metallization in bulk, behavior of Vth profile over composition and corrosion reactions. In this thesis work, fast ion conducting (FIC) AgI-Ag2O-MoO3 glasses have been investigated with an idea to solve some technical challenges such as thermal stability, corrosion etc. with the help of deep understanding of the material. Employing various experimental and characterization techniques, this research work aims to identify the links between various material and technical aspects and how to tune these aspects to solve the challenges envisaged.
Bulk AgI-Ag2O-MoO3 (50:25:25) glasses have been prepared by melt quenching method (Microwave heating and quenched between two heavy steel plates). The electrical switching experiments have been carried out using a Keithley Source Meter (model 2410) controlled by Lab VIEW 6i, on samples of thicknesses (d) 0.1, 0.2 and 0.3 mm at different ON state currents (Imax) (3 mA, 2 mA, 1 mA, 0.6 mA, 0.4 mA and 0.25 mA); It has been found that these samples exhibit fast near ideal memory switching. The power dissipation (P) increases with both d and Imax. It is also found that the threshold voltage (Vth) increases with d; and for a given thickness, the Vth decreases with increasing Imax. A sample of d = 0.1 mm exhibits near ideal memory switching with the least P for Imax = 0.25 mA. These samples can be used for fast switching applications with minimum power dissipation. Further, the electrical switching behavior of bulk, FIC (AgI)50+x-(Ag2O)25-(MoO3)25-x, for 10 ≤ x ≤ -10 glasses has been investigated, in order to understand the switching mechanism of bulk samples with the inert electrodes. It is found that by using inert electrodes, the switching becomes irreversible, memory type. In these samples, the switching mechanism is an electrochemical metallization process. The inert electrodes restrain ionic mass transfer; however exhibit a low barrier to electron transfer allowing the cathodic metallization reaction to reach Nernst equilibrium faster. The cations involved in this process transport thorough the free volume within the glass structure and follows Mott-Gurney (MG) model for electric field driven thermally activated ion hopping conductivity. This model along with the thermal stability profile provide a narrow region within composition with better switching performance based on swiftness to reach Vth and less power loss. It is found that traces of anionic contribution to metallization are absent. Moreover, anodic oxidation involves reactions that cause bubble formation and corrosion which becomes evident from SEM (Scanning electron Microscope) micrographs of the switched and un-switched parts of the sample.
Rigidity percolation phenomena in (AgI)50+x-(Ag2O)25-(MoO3)25-x, for 5 ≤ x ≤ -12.5 has been observed by performing calorimetry (ADSC) and photoelectron spectroscopy experiments (XPS). The temperature dependence of heat capacity (normalized Cp) at glass transition temperature (Tg), exhibits fluctuations for samples with higher AgI concentration indicating the fragile nature of the glass. The composition range chosen in the present study, accommodates both the fragile and strong glasses, and the fragility threshold. Cp (absolute) values, at Tg, exhibits abrupt sign shift at this threshold. The negative Cp is identified as a thermodynamic behavior of nanoclusters. The XPS study shows the formation of covalent structural units, [‒Mo‒O‒Ag‒O‒] and complex molybdenum oxides in the positive Cp region. Finally, the non-reversing enthalpy profile, exhibits square well minima, sandwiched between floppy and stress rigid region, which has been identified to be the intermediate phase, within the range 32.25 ≤ MoO3 concentration ≤ 35.
Electrochemical Impedance Spectroscopy (EIS) and Raman studies have been performed on this glass, over a wide range of composition ((AgI)50+x-(Ag2O)25-(MoO3)25-x, for 3.75 ≤ x ≤ -10.5) to understand the features of structure, ion migration and their correlation. These features essentially involve diffusion and relaxation. The coefficients associated with diffusion process, especially, the diffusion coefficient, diffusion length and relaxation time has been determined by applying Nguyen-Breitkopf method. Besides, by tuning the concentration of the constituents, it is possible to obtain samples which exhibit two important structural characteristics, namely fragility and polymeric phase formation. The present study essentially addresses these issues and endeavors to figure out the corroboration among them. The relaxation behavior, when scrutinized in the light of Diffusion Controlled Relaxation (DCR) model, ascertains the fragility threshold which is also identified as the margin between the two types of polymeric phases. Simultaneously, it fathoms into the equivalent circuitry, its elements and their behavioral changes with above mentioned features. The power law behavior of A.C. conductivity exhibits three different non-Jonscher type dispersive regimes along with a high frequency plateau. The sub-linearity and super-linearity remain significantly below and above the Jonscher’s carrier transport limit, 0.5 ≤ n ≤ 0.9. Finally, by observing the behavior of the crossover between these sun-linear and super-linear (SLPL) regime, an intuitive suggestion has been proposed for the appearance of SLPL: oxygen vacancy formation.
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Green, Brandice Annette. « Localized Corrosion Behavior of Zr-based Bulk Metallic Glasses in Neutral NaCl Electrolytes ». 2008. http://trace.tennessee.edu/utk_graddiss/532.
Texte intégralRésumé :
The electrochemical behaviors the Zr50Cu40Al10, Zr50Cu33Al10Pd7, and Zr52.5Cu17.9Al10Ni14.6Ti5.0 BMGs were investigated in NaCl solutions. Both Zr50Cu40Al10 and Zr50Cu33Al10Pd7 exhibited poor corrosion behaviors. Zr50Cu40Al10 was vulnerable to localized corrosion at the open-circuit conditions (OCC). Zr50Cu33Al10Pd7 experienced localized corrosion at OCC or at slightly higher potentials. Anodic-polarization of both alloys demonstrated that small increases in the applied potential resulted in significant increases in the current density. Scanning electron microscopy examination of the corroded surfaces of both the Zr50Cu40Al10 and Zr50Cu33Al10Pd7 BMGs revealed that an oxide layer formed on the surfaces after the exposure to the chloride solutions. In both cases, the growth pattern of the oxide seemed to be related to a dendritic structure. Scanning Auger microanalysis of the heavily corroded areas on Zr50Cu40Al10 showed that the attacked regions were enriched with Cu, Cl, and O. Higher concentrations of Pd and Cu were observed in pits as opposed to the surface of Zr50Cu33Al10Pd7. A corrosion mechanism related to a galvanic electrode effect and the formation of CuCl and CuO was proposed.
The anodic-polarization behavior of Zr52.5Cu17.9Al10Ni14.6Ti5.0 (Vitreloy 105) was improved over the behaviors of Zr50Cu40Al10 and Zr50Cu33Al10Pd7. Corrosion investigations were performed on samples obtained from regions transverse to and along the long axis of Vitreloy 105 ingots. “Swirl” features, usually thought to be areas of crystallinity, were visible in the longitudinal samples. Some longitudinal samples were treated with a laser in attempts to induce crystallinity. The cross-sectional samples were passivated at OCC; however, pits did initiate after significant overpotentials were applied. Some regions of the pits had a porous morphology that was enriched with Cu. The longitudinal samples also exhibited passive behavior at OCC. However, despite the presence of the “swirl” regions, the longitudinal samples were immune to pitting corrosion for the tested potential range. In-situ AFM experiments were performed on longitudinal samples in 0.6 M NaCl at an applied potential of -190 mV, SCE. Generally, the height of the surface increased with time, which was thought to be related to the thickening of the passive film. This observation may be associated with the improved pitting resistance of the longitudinal samples.
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Kuo, Kuan-yuan, et 郭寬淵. « Study of Wire Electrochemical Discharge Machining (WECDM) of Quartz Glass with Titrated Electrolyte Flow ». Thesis, 2015. http://ndltd.ncl.edu.tw/handle/91357165184471106269.
Texte intégralRésumé :
博士國立中央大學
機械工程學系
103
Quartz has excellent properties, but its brittleness property results in the difficulty of balance between efficiency and precision for traditional machining method. ECDM aids in machining with high temperature fusion and etching, and is very appropriate for quartz material. In WECDM machining system, uneasy control of insulation gas film structure and difficult electrolyte circulation in machining zone. Therefore, thesis topic is to explore WECDM machining mechanisms, development new methods and improve the micro slit surface quality. First, investigate the flow of electrolyte influence on the processing of quartz glass, adding graphite powder or silicon carbide powder of composite processing methods to improve the processing efficiency and accuracy. From experimental results, the surface roughness value for electrolyte WECDM machining without adding any powder under the same condition is Ra＝1.13μm, while the surface roughness may achieve Ra＝0.36μm as 0.4wt％ of graphite is added into electrolyte . The improvement rate is 68%. As 5wt％ of silicon carbide is added into electrolyte, the surface roughness can achieve Ra＝0.22μm, that is, the improvement rate is 80%. Furthermore, electrolyte is used very few under the best appropriate condition. It is proved that the utilization of graphite or silicon carbide characteristics for local machining of quartz glass in titration electrolyte is advantageous of improving surface quality effectively, reducing environmental pollution, lowering cost, and achieving one-time machining to reduce machining procedures.
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YANG, ZHONG-DAO, et 楊中道. « Liquid phase bonding of 3Y-TZ with CaO-TiO2 -SiO2 glass slurry and electrical behavior of Nd2 O3 -doped Ce-ZrO2 solid state electrolyte ». Thesis, 1990. http://ndltd.ncl.edu.tw/handle/80975274452166539770.
Texte intégral
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Chen, Chun Yi, et 陳駿逸. « Study of the electrochemical oxidation of dissolved CO in acidic and alkaline electrolyte by using pulse-electrodeposition fabricated gold and gold-platinum alloy nano-clusters on glass carbon RDE ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/88663853696423733413.
Texte intégralRésumé :
碩士長庚大學
化工與材料工程學系
100
The fabrication of gold and gold-platinum clusters on glass carbon rotating disc electrode (RDE) by using pulse-electrodeposition and co-electrodeposition approaches, and the metal clusters on glass carbon RDE were characterized by cyclic voltammetry to examine forced convection of the solution phase carbon monoxide (CO) electrochemical oxidation on metal cluster electrodes in alkaline and acid electrolyte. The oxidation currents of dissolved CO (10-3 M) on gold electrode in 1 M perchloric acid exhibits pure diffusion control behavior by using rotating disc electrode. The cyclic voltammograms features of the co-electrodeposited gold-platinum clusters on glass carbon indicate the characteristics of gold-platinum bimetallic and the limiting currents of the electrochemical oxidation of CO on the Au-Pt RDE indicated the adsorbed CO effect on the electrochemical oxidation of dissolved CO. The intrinsic properties of gold-platinum alloy may affect the electrochemical oxidation of the dissolved carbon monoxide by surface adsorbed CO due to the change of electronic band structures of Pt interactions to gold. The results of CO electrochemical oxidation potential in alkaline system are lower than the acid and the carbon monoxide current in alkaline system are lower than the acid system.