Download or read book Electrochemical Studies of Mobile Charged Species During Zirconium Alloy Oxidation written by James Stephen Smith and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This research has used a suite of electrochemical techniques, both in-situ and ex-situ to investigate the mobile charged species in the oxides of zirconium alloys. Limits on the corrosion resistance of existing zirconium alloys used for fuel cladding are a major restriction on the burn-up that can be achieved within a pressurised water reactor (PWR). Developing a full mechanistic understanding of the corrosion process of zirconium alloys in the primary water environment is necessary for prolonging the life-time of fuel cladding. A key component in the corrosion of zirconium alloy is the transport properties of various charged species within the oxide layer, which determine the rate of corrosion. Three distinct electrochemical methods have been employed in this work. The first technique, Electrochemical Impedance Spectroscopy (EIS), has been used to determine the physical properties of the oxide. The second technique, Mott-Schottky analysis, studied the oxide acceptor/donor densities; hence the nature, concentration and activation energy of the major electronic charge carrier could be determined. The final method, a DC method known as Wagner-asymmetric polarization (WAP), separated the ionic and electronic currents and can thus allow the calculation of transport numbers, partial conductivities and activation energies of the ionic species. All the techniques investigated parameters as a function of oxidation time, lithium concentration and alloying elements. Work was carried out on oxides grown under PWR conditions (2 ppm Li and 1000 ppm B) at temperatures of 240-360 °C on specimens of zircaloy-4, ZIRLO, Zr-0.1%Nb and Zr-1%Nb. The EIS was undertaken in-situ to determine the oxide thickness and showed that the electrochemically active oxide grows quicker in a higher lithium concentration. Variances in oxide growth rates are also seen between specimens of differing niobium and tin content. In-situ Mott-Schottky analysis of the electronic charge carriers within the thin oxide showed the oxide to be a n-type semiconductor. Hence the dominant charge carriers, for early stage oxidation of Zircaloy-4 under simulated PWR conditions, were electrons with a donor density of approximately 2 x 1017 cm-3. The addition of lithium to the oxidation environment increases the donor density, which indicates lithium plays a previously unknown active role in the corrosion process. Despite the oxide being highly resistive, this research has also shown that the ionic charge carriers within the oxide can be directly measured using asymmetric-polarisation. However, further work needs to be undertaken to perfect this technique under inert atmospheres.

Download or read book First principles Based Treatment of Charged Species Equilibria at Electrochemical Interfaces Model System of Zirconium Oxide and Titanium Oxide written by Jing Yang (Ph. D.) and published by . This book was released on 2020 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ionic defects are known to influence the magnetic, electronic and transport properties of oxide materials. Understanding defect chemistry provides guidelines for defect engineering in various applications including energy storage and conversion, corrosion, and neuromorphic computing devices. While DFT calculations have been proven as a powerful tool for modeling point defects in bulk oxide materials, challenges remain for linking atomistic results with experimentally-measurable materials properties, where impurities and complicated microstructures exist and the materials deviate from ideal bulk behavior. This thesis aims to bridge this gap on two aspects. First, we study the coupled electro-chemo-mechanical effects of ionic impurities in bulk oxide materials. Second, we develop a modeling framework for describing point defect redistribution at extended defects, including grain boundaries, oxide/oxide interfaces, and oxide/water interfaces. The first part of this thesis deals with zirconium oxide in the context of corrosion of zirconium alloys used as nuclear cladding materials in light water reactors. We provide physically-deduced diffusion coefficients for higher-level modeling as well as better mechanistic understanding of zirconium alloy corrosion by studying defect equilibria in ZrO2 passive films. A first-principles based model for predicting charged species redistribution profiles at electrochemical interfaces is established and applied to ZrO2/Cr2O3 and ZrO2/water interfaces, and ZrO2 grain boundaries. Defect redistribution at these extended defects can lead to significant changes in transport properties of oxides. The second part applies similar methodology to TiO2 as a model system for studying field-assisted sintering (FAST). FAST has been demonstrated for multiple ceramic materials as a promising sintering technique for shortening consolidation times and lowering sintering temperatures. By studying the defect chemistry of acceptor- and donor-TiO2 and designing experiments accordingly, we show that while Joule heating is the dominant effect of the applied electric field, the shrinkage rate also correlates strongly with titanium diffusivity. Through donor doping, which increases the concentrations of fast-diffusing titanium interstitials, a higher shrinkage rate is achievable. These results prove that first-principles base calculations are capable of predicting the defect chemistry of oxide materials that quantitatively agree with measured values. Such understanding of defect chemistry gives insights into practical defect engineering strategies that are broadly applicable to electrochemical applications.

Download or read book Electrochemical and Polarographic Studies on the Corrosion of Zirconium in Presence of Various Aqueous Media written by George B. Adams (Jr.) and published by . This book was released on 1953 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1973 with total page 990 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nuclear Power Reactor Instrumentation Systems Handbook written by Joseph M. Harrer and published by . This book was released on 1973 with total page 1052 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Journal of the Electrochemical Society written by Electrochemical Society and published by . This book was released on 1958 with total page 1046 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues for 19 - contain separately paged section consisting of editorials and various special features.

Download or read book Electrochemical Technology written by and published by . This book was released on 1966 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Zirconium in the Nuclear Industry Tenth International Symposium written by A. M. Garde and published by ASTM International. This book was released on 1994 with total page 805 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Corrosion Science and Technology written by Mars Guy Fontana and published by . This book was released on 1970 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Corrosion Abstracts written by and published by . This book was released on 1984 with total page 682 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plasma Electrolytic Oxidation PEO Coatings written by Marta Mohedano and published by MDPI. This book was released on 2021-06-02 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma electrolytic oxidation (PEO), also known as micro-arc oxidation (MAO), functionalizes surfaces, improving the mechanical, thermal, and corrosion performance of metallic substrates, along with other tailored properties (e.g., biocompatibility, catalysis, antibacterial response, self-lubrication, etc.). The extensive field of applications of this technique ranges from structural components, in particular, in the transport sector, to more advanced fields, such as bioengineering. The present Special Issue covers the latest advances in PEO‐coated light alloys for structural (Al, Mg) and biomedical applications (Ti, Mg), with 10 research papers and 1 review from leading research groups around the world.

Download or read book Electrochemistry for Materials Science written by Walfried Plieth and published by Elsevier. This book was released on 2008-01-08 with total page 433 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the principles of electrochemistry with a special emphasis on materials science. This book is clearly organized around the main topic areas comprising electrolytes, electrodes, development of the potential differences in combining electrolytes with electrodes, the electrochemical double layer, mass transport, and charge transfer, making the subject matter more accessible.In the second part, several important areas for materials science are described in more detail. These chapters bridge the gap between the introductory textbooks and the more specialized literature. They feature the electrodeposition of metals and alloys, electrochemistry of oxides and semiconductors, intrinsically conducting polymers, and aspects of nanotechnology with an emphasis on the codeposition of nanoparticles.This book provides a good introduction into electrochemistry for the graduate student. For the research student as well as for the advanced reader there is sufficient information on the basic problems in special chapters. The book is suitable for students and researchers in chemistry, physics, engineering, as well as materials science.- Introduction into electrochemistry- Metal and alloy electrodeposition- Oxides and semiconductors, corrosion- Intrinsically conducting polymers- Codeposition of nanoparticles, multilayers

Download or read book Corrosion and Surface Chemistry of Metals written by Dieter Landolt and published by EPFL Press. This book was released on 2007-05-02 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt: Textbook; grad.

Download or read book Metals Abstracts Index written by and published by . This book was released on 1996 with total page 1622 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Intermediate Temperature Solid Oxide Fuel Cells written by Gurbinder Kaur and published by Elsevier. This book was released on 2019-11-21 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt: Intermediate Temperature Solid Oxide Fuel Cells: Electrolytes, Electrodes and Interconnects introduces the fundamental principles of intermediate solid oxide fuel cells technology. It provides the reader with a broad understanding and practical knowledge of the electrodes, pyrochlore/perovskite/oxide electrolytes and interconnects which form the backbone of the Solid Oxide Fuel Cell (SOFC) unit. Opening with an introduction to the thermodynamics, physiochemical and electrochemical behavior of Solid Oxide Fuel Cells (SOFC), the book also discusses specific materials, including low temperature brownmillerites and aurivillius electrolytes, as well as pyrochlore interconnects. This book analyzes the basic concepts, providing cutting-edge information for both researchers and students. It is a complete reference for Intermediate Solid Oxide Fuel Cells technology that will be a vital resource for those working in materials science, fuel cells and solid state chemistry. - Provides a single source of information on glass, electrolytes, interconnects, vanadates, pyrochlores and perovskite SOFC - Includes illustrations that provide a clear visual explanation of concepts being discussed - Progresses from a discussion of basic concepts that will enable readers to easily comprehend the subject matter

Download or read book Polymer Electrolyte Fuel Cell Durability written by Felix N. Büchi and published by Springer Science & Business Media. This book was released on 2009-02-08 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers a significant number of R&D projects, performed mostly after 2000, devoted to the understanding and prevention of performance degradation processes in polymer electrolyte fuel cells (PEFCs). The extent and severity of performance degradation processes in PEFCs were recognized rather gradually. Indeed, the recognition overlapped with a significant number of industrial dem- strations of fuel cell powered vehicles, which would suggest a degree of technology maturity beyond the resaolution of fundamental failure mechanisms. An intriguing question, therefore, is why has there been this apparent delay in addressing fun- mental performance stability requirements. The apparent answer is that testing of the power system under fully realistic operation conditions was one prerequisite for revealing the nature and extent of some key modes of PEFC stack failure. Such modes of failure were not exposed to a similar degree, or not at all, in earlier tests of PEFC stacks which were not performed under fully relevant conditions, parti- larly such tests which did not include multiple on–off and/or high power–low power cycles typical for transportation and mobile power applications of PEFCs. Long-term testing of PEFCs reported in the early 1990s by both Los Alamos National Laboratory and Ballard Power was performed under conditions of c- stant cell voltage, typically near the maximum power point of the PEFC.

Download or read book New Promising Electrochemical Systems for Rechargeable Batteries written by V. Barsukov and published by Springer Science & Business Media. This book was released on 1996-02-29 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: Electricity is the most important secondary energy source, the present production rate, mainly from thermal electric power stations, being of the order of 1.3 TW. However, the total capacity of primary and rechargeable batteries currently in use is the same as the output of the world's power stations. But present battery systems will not meet future needs for the economical storage of large amounts of electrical energy for vehicles, public transport, road levelling, solar energy utilisation, civil video and audio, terrestrial and space communications, etc. Current accumulators based on aqueous acid or alkali systems do not have sufficient output and, moreover, the materials employed (Pb, Cd, Ni) are environmental pollutants that require safe recycling. Further, stocks of these strategic metals are being rapidly depleted. This book discusses actual field results with novel systems, such as rechargeable lithium batteries, zinc/air cells, metal-free accumulators, graphite/carbon devices and others, including fuel cells. The book stresses that a universal electrochemical system is not feasible: the choice of any system must depend on the concrete field of application and must be taken in consideration of a large number of technical, economic and environmental circumstances.