Download or read book Theory and Simulation Methods for Electronic and Phononic Transport in Thermoelectric Materials written by Neophytos Neophytou and published by . This book was released on 2020 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces readers to state-of-the-art theoretical and simulation techniques for determining transport in complex band structure materials and nanostructured-geometry materials, linking the techniques developed by the electronic transport community to the materials science community. Starting from the semi-classical Boltzmann Transport Equation method for complex band structure materials, then moving on to Monte Carlo and fully quantum mechanical models for nanostructured materials, the book addresses the theory and computational complexities of each method, as well as their advantages and capabilities. Presented in language that is accessible to junior computational scientists, while including enough detail and depth with regards to numerical implementation to tackle modern research problems, it offers a valuable resource for computational scientists and postgraduate researchers whose work involves the theory and simulation of electro-thermal transport in advanced materials.

Download or read book Theory and Simulation Methods for Electronic and Phononic Transport in Thermoelectric Materials written by Neophytos Neophytou and published by Springer Nature. This book was released on 2020-03-16 with total page 97 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces readers to state-of-the-art theoretical and simulation techniques for determining transport in complex band structure materials and nanostructured-geometry materials, linking the techniques developed by the electronic transport community to the materials science community. Starting from the semi-classical Boltzmann Transport Equation method for complex band structure materials, then moving on to Monte Carlo and fully quantum mechanical models for nanostructured materials, the book addresses the theory and computational complexities of each method, as well as their advantages and capabilities. Presented in language that is accessible to junior computational scientists, while including enough detail and depth with regards to numerical implementation to tackle modern research problems, it offers a valuable resource for computational scientists and postgraduate researchers whose work involves the theory and simulation of electro-thermal transport in advanced materials.

Download or read book Electron and Phonon Transport in Disordered Thermoelectric Materials written by Simon Thébaud and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decades, the increasingly pressing need for clean energy sources and the realization that a huge proportion of the world energy consumption is wasted in heat have prompted great interest in developing efficient thermoelectric generation modules. These devices could harvest waste heat from industrial processes or other sources, turning a temperature gradient into a voltage through the Seebeck effect. Efficient thermoelectric materials should exhibit a low thermal conductivity, a high electrical conductivity and a high Seebeck coefficient. Simultaneously optimizing these parameters is a great challenge of condensed matter physics and materials science. With a view to enhance the thermoelectric properties of several promising materials, we explore several strategies in which defects (atomic substitutions, vacancies...), disorder and dimensional confinement play a crucial role. We perform density functional theory calculations and projections on Wannier orbitals to construct realistic Hamiltonians and dynamical matrices describing their electronic and vibrational structure in real space. These parameters are then used to compute the thermoelectric transport properties using the Kubo formalism, the Boltzmann transport equation, the Landauer formalism, and the Chebyshev polynomial Green's function method that allows for an exact treatment of disorder. We investigate the electronic transport properties and thermoelectric performances of two promising materials for high-temperature power generation, strontium titanate and rutile titanium dioxide. Comparison of our predictions with a wealth of experimental data yields a very good agreement. We show that the increase of the Seebeck coefficient observed in strontium titanate superlayers, until now attributed to quantum confinement effects, is in fact well explained assuming delocalized electrons. The general effects of resonant states on electronic transport are explored in a model study, showing a sixfold increase of the thermoelectric performances. The particular case of strontium titanate is then examined, and localization effects are shown to destroy the performances if Vanadium atoms are introduced as resonant impurities. The influence of defects in two-dimensional materials is investigated. Contrary to adatoms, substitutions in transition metal dichalcogenides are shown to localize the charge carriers. We study the effect of vacancies on phonon transport in graphene, and determine the phonon-vacancy scattering rate. Comparison with thermal conductivity data for irradiated and finite-size graphene samples yields a very good agreement between theory and experiments.

Download or read book Novel Applications of Piezoelectric and Thermoelectric Materials written by Rafael Vargas-Bernal and published by BoD – Books on Demand. This book was released on 2024-01-31 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Piezoelectric and thermoelectric materials represent emerging cutting-edge technological materials for energy harvesting for high-value-added applications. Although these materials have been exhaustively exploited for decades, researchers around the world continue to find technological and scientific innovations that must be disseminated to the engineers of yesterday, today, and tomorrow. Piezoelectric materials, through mechanical stresses applied to them, are capable of generating electricity, while thermoelectric materials are capable of producing electricity thanks to the heat applied to them. Therefore, the direct application of these materials is in energy harvesting, which, together with the reduction of materials, leads them to portable and wearable functional applications. The purpose of this work is to disseminate some of the latest scientific and technological advances by different researchers around the world in the development of devices and applications based on these materials. The book compiles state-of-the-art fundamentals, current uses, as well as emerging applications of piezoelectric and thermoelectric materials. It is a source of inspiration for continued scientific research on the commercial, industrial, and military applications of these materials. Furthermore, it is a valuable and informative resource for undergraduate and graduate students, as well as experts and researchers in the field.

Download or read book Refrigerators Heat Pumps and Reverse Cycle Engines written by Jocelyn Bonjour and published by John Wiley & Sons. This book was released on 2023-08-29 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nanoscale Electron Phonon and Spin Transport in Thermoelectric Materials written by Bolin Liao (Ph. D.) and published by . This book was released on 2016 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climate change is among the most critical challenges that are facing the human race in the 21st century. One of the major factors that leads to climate change is the increasing consumption of fossil fuels, driven by industrialization and economic growth at an unprecedented pace. For a secure and sustainable future of energy and the environment, new clean and efficient energy technologies are in urgent need. Thermoelectric materials are a group of materials that can directly convert heat into electricity. Being solid state, clean, reliable and without moving parts, thermoelectric energy conversion holds great promise as a candidate technology to harvest energy from thermal sources, such as the sun and terrestrial heat sources, as well as improve the efficiency of existing energy systems by recycling the inevitable waste heat. The bottleneck that prevents large-scale deployment of thermoelectric modules so far, however, is the relatively low efficiency and high cost. A good thermoelectric material needs to conduct electricity well and conduct heat poorly to attain high efficiency. Remarkable progress has been made in the past decade to decouple the charge and heat transport and thus improve the material performance. Most of the progress has been based on a more detailed understanding of the transport and interaction of fundamental energy carriers, such as electrons and phonons in most semiconductors, and magnons in magnetic materials. These understandings have been achieved through the development of both first-principles simulations and experimental spectroscopic tools, in particular for phonon transport and phonon-phonon interaction, which have enabled calculations and measurements at the single-phonon-mode level. Information gained from these studies formed the foundation of the successful engineering efforts of designing nanostructured thermoelectric materials. Although the nanostructuring approach has been able to reduce the thermal conductivity of thermoelectric materials down to proximity of the amorphous limit, it has been realized by the community that further improvement of thermoelectric materials requires breakthroughs in boosting the electrical transport properties, including the electrical conductivity and the Seebeck coefficient. Despite several existing strategies, a prerequisite for systematic improvement is, again, insight into the transport and interaction of fundamental carriers, particularly involving electrons, at the single-mode level. This insight has largely remained lacking in terms of electrons, both on the simulation side and on the experimental side. This thesis aims to develop both simulation and experimental tools to study nanoscale electron, phonon and magnon transport and their interactions, with a particular emphasis on understanding the electron-phonon interaction at the single-mode level. This is among the most important forms of carrier interactions and determines the intrinsic electron transport properties of most conductors. Regarding phonon transport, we applied first-principles lattice dynamics to study phonon-phonon interaction and lattice thermal conductivity in a strongly-correlated thermoelectric compound FeSb 2. On electronphonon interactions, we studied from first-principles the intrinsic electrical transport properties of phosphorene, which are limited by electron-phonon interactions, analyzed its anisotropy and evaluated its potential as a thermoelectric material; we studied how free carriers can in turn scatter phonons through the electron-phonon interaction and reduce the lattice thermal conductivity; to verify this finding, we designed an ultrafast photoacoustic spectroscopic technique to directly detect the damping of a single phonon mode due to electron-phonon interaction. On phonon-magnon interactions, we applied the coupled Boltzmann equation to analyze coupled phonon-magnon diffusion and proposed a novel magnon cooling effect. These fundamental discoveries can potentially lead to new design principles for more efficient thermoelectric materials in the future.

Download or read book Novel Thermoelectric Materials and Device Design Concepts written by Sergey Skipidarov and published by Springer Nature. This book was released on 2019-12-17 with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents and facilitates the interchange of new research and development results concerned with hot topics in thermoelectric generators (TEGs) research, development and production. Topics include prospective thermoelectric materials for manufacturing TEGs operating in low-, mid-, and high temperature ranges, thermal and mechanical degradation issues in prospective thermoelectric materials and TEG modules, theoretical study of novel inorganic and organic thermoelectric materials, novel methods and apparatus for measuring performance of thermoelectric materials and TEGs, and thermoelectric power generators simulation, modeling, design and practice.This book helps researchers tackle the challenges that still remain in creating cheap and effective TEGs and presents the latest trends and technologies in development and production of advanced thermoelectric generation devices. Provides a concentration of new research and development in the field of Thermoelectric energy generation; Facilitates the interchange of new ideas and results to react effectively to the challenges of Thermoelectric generators; Explains both the advancements and challenges in TEGs.

Download or read book Electronic Transport Theories written by Navinder Singh and published by CRC Press. This book was released on 2016-11-17 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Maintaining a practical perspective, Electronic Transport Theories: From Weakly to Strongly Correlated Materials provides an integrative overview and comprehensive coverage of electronic transport with pedagogy in view. It covers traditional theories, such as the Boltzmann transport equation and the Kubo formula, along with recent theories of transport in strongly correlated materials. The understood case of electronic transport in metals is treated first, and then transport issues in strange metals are reviewed. Topics discussed are: the Drude-Lorentz theory; the traditional Bloch-Boltzmann theory and the Grüneisen formula; the Nyquist theorem and its formulation by Callen and Welton; the Kubo formalism; the Langevin equation approach; the Wölfle-Götze memory function formalism; the Kohn-Luttinger theory of transport; and some recent theories dealing with strange metals. This book is an invaluable resource for undergraduate students, post-graduate students, and researchers with a background in quantum mechanics, statistical mechanics, and mathematical methods.

Download or read book Thermoelectric Materials and Devices written by Lidong Chen and published by Elsevier. This book was released on 2020-09-25 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermoelectric Materials and Devices summarizes the latest research achievements over the past 20 years of thermoelectric material and devices, most notably including new theory and strategies of thermoelectric materials design and the new technology of device integration. The book's author has provided a bridge between the knowledge of basic physical/chemical principles and the fabrication technology of thermoelectric materials and devices, providing readers with research and development strategies for high performance thermoelectric materials and devices. It will be a vital resource for graduate students, researchers and technologists working in the field of energy conversion and the development of thermoelectric devices. - Discusses the new theory and methods of thermoelectric materials design - Combines scientific principles, along with synthesis and fabrication technologies in thermoelectric materials - Presents the design optimization and interface technology for thermoelectric devices - Introduces thermoelectric polymers and organic-inorganic thermoelectric composites

Download or read book Thermoelectrics written by HoSung Lee and published by John Wiley & Sons. This book was released on 2016-09-07 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermoelectrics: Design and Materials HoSung Lee, Western Michigan University, USA A comprehensive guide to the basic principles of thermoelectrics Thermoelectrics plays an important role in energy conversion and electronic temperature control. The book comprehensively covers the basic physical principles of thermoelectrics as well as recent developments and design strategies of materials and devices. The book is divided into two sections: the first section is concerned with design and begins with an introduction to the fast developing and multidisciplinary field of thermoelectrics. This section also covers thermoelectric generators and coolers (refrigerators) before examining optimal design with dimensional analysis. A number of applications are considered, including solar thermoelectric generators, thermoelectric air conditioners and refrigerators, thermoelectric coolers for electronic devices, thermoelectric compact heat exchangers, and biomedical thermoelectric energy harvesting systems. The second section focuses on materials, and covers the physics of electrons and phonons, theoretical modeling of thermoelectric transport properties, thermoelectric materials, and nanostructures. Key features: Provides an introduction to a fast developing and interdisciplinary field. Includes detailed, fundamental theories. Offers a platform for advanced study. Thermoelectrics: Design and Materials is a comprehensive reference ideal for engineering students, as well as researchers and practitioners working in thermodynamics. Cover designed by Yujin Lee

Download or read book Exploring Electron and Phonon Transport at the Nanoscale for Thermoelectric Energy Conversion written by Austin Jerome Minnich and published by . This book was released on 2011 with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermoelectric materials are capable of solid-state direct heat to electricity energy conversion and are ideal for waste heat recovery applications due to their simplicity, reliability, and lack of environmentally harmful working fluids. Recently, nanostructured thermoelectrics have demonstrated remarkably enhanced energy conversion efficiencies, primarily due to a reduction in lattice thermal conductivity. Despite these advances, much remains unknown about heat transport in these materials, and further efficiency improvements will require a detailed understanding of how the heat carriers, electrons and phonons, are affected by nanostructures. To elucidate these processes, in this thesis we investigate nanoscale transport using both modeling and experiment. The first portion of the thesis studies how electrons and phonons are affected by grain boundaries in nanocomposite thermoelectric materials, where the grain sizes are smaller than mean free paths (MFPs). We use the Boltzmann transport equation (BTE) and a new grain boundary scattering model to understand how thermoelectric properties are affected in nanocomposites, as well as to identify strategies which could lead to more efficient materials. The second portion of the thesis focuses on determining how to more directly measure heat carrier properties like frequency-dependent MFPs. Knowledge of phonon MFPs is crucial to understanding and engineering nanoscale transport, yet MFPs are largely unknown even for bulk materials and few experimental techniques exist to measure them. We show that performing macroscopic measurements cannot reveal the MFPs; instead, we must study transport at the scales of the MFPs, in the quasi- ballistic transport regime. To investigate transport at these small length scales, we first numerically solve the frequency-dependent phonon BTE, which is valid even in the absence of local thermal equilibrium, unlike heat diffusion theory. Next, we introduce a novel thermal conductivity spectroscopy technique which can measure MFP distributions over a wide range of length scales and materials using observations of quasi-ballistic heat transfer in a pump-probe experiment. By observing the changes in thermal resistance as a heated area size is systematically varied, the thermal conductivity contributions from different MFP phonons can be determined. We present the first experimental measurements of the MFP distribution in silicon at cryogenic temperatures. Finally, we develop a modification of this technique which permits us to study transport at scales much smaller than the diffraction limit of approximately one micron. It is important to access these length scales as many technologically relevant materials like thermoelectrics have MFPs in the deep submicron regime. To beat the diffraction limit, we use electron-beam lithography to pattern metallic nano dot arrays with diameters in the hundreds of nanometers range. Because the effective length scale for heat transfer is the dot diameter rather than the optical beam diameter, we are able to study nanoscale heat transfer while still achieving ultrafast time resolution. We demonstrate the modified technique by measuring the MFP distribution in sapphire. Considering the crucial importance of the knowledge of MFPs to understanding and engineering nanoscale transport, we expect these newly developed techniques to be useful for a variety of energy applications, particularly for thermoelectrics, as well as for gaining a fundamental understanding of nanoscale heat transport.

Download or read book Thermoelectrics written by N. M. Ravindra and published by Springer. This book was released on 2018-08-29 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a concise but comprehensive introduction to the fundamentals and current state of the art in thermoelectrics. Addressing an audience of materials scientists and engineers, the book covers theory, materials selection, and applications, with a wide variety of case studies reflecting the most up-to-date research approaches from the past decade, from single crystal to polycrystalline form and from bulk to thin films to nano dimensions. The world is facing major challenges for finding alternate energy sources that can satisfy the increasing demand for energy consumption while preserving the environment. The field of thermoelectrics has long been recognized as a potential and ideal source of clean energy. However, the relatively low conversion efficiency of thermoelectric devices has prevented their utility on a large scale. While addressing the need for thermal management in materials, device components, and systems, thermoelectrics provides a fundamental solution to waste heat recovery and temperature control. This book summarizes the global efforts that have been made to enhance the figure of merit of various thermoelectric materials by choosing appropriate processes and their influence on properties and performance. Because of these advances, today, thermoelectric devices are found in mainstream applications such as automobiles and power generators, as opposed to just a few years ago when they could only be used in niche applications such as in aeronautics, infrared imaging, and space. However, the continued gap between fundamental theoretical results and actual experimental data of figure of merit and performance continues to challenge the commercial applications of thermoelectrics. This book presents both recent achievements and continuing challenges, and represents essential reading for researchers working in this area in universities, industry, and national labs.

Download or read book Modern Theory of Thermoelectricity written by Veljko Zlatic and published by OUP Oxford. This book was released on 2014-05-22 with total page 303 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, there have been important developments in the design and fabrication of new thermoelectrics. While a decade ago, progress was mainly empirical, recent advances in theoretical methods have led to a deeper understanding of the parameters that affect the performance of materials in thermoelectric devices. These have brought the goal of producing materials with the required characteristics for commercial application a significant step closer. A search for efficient materials requires a fully microscopic treatment of the charge and heat transport, and the aim of this book is to explain all thermoelectric phenomena from this modern quantum-mechanical perspective. In the first part on phenomenology, conjugate current densities and forces are derived from the condition that the rate of change of the entropy density of the system in the steady state is given by the scalar product between them. The corresponding transport coefficients are explicitly shown to satisfy Onsager's reciprocal relations. The transport equations are solved for a number of cases, and the coefficient of performance, the efficiency, and the figure of merit are computed. State-of-the-art methods for the solution of the transport equations in inhomogeneous thermoelectrics are presented. A brief account on how to include magnetization transport in the formalism is also given. In the second part, quantum mechanical expressions for the transport coefficients are derived, following the approach by Luttinger. These are shown to satisfy Onsager's relations by construction. Three lattice models, currently used to describe strongly correlated electron systems, are introduced: the Hubbard, the Falicov-Kimball, and the periodic Anderson model (PAM), and the relevant current density operators are derived for each of them. A proof of the Jonson-Mahan theorem, according to which all transport coefficients for these models can be obtained from the integral of a unique transport function multiplied by different powers of the frequency, is given. The third part compares theory and experiment. First for the thermoelectric properties of dilute magnetic alloys, where the theoretical results are obtained from poor man's scaling solutions to single impurity models. Then it is shown that the experimental data on heavy fermions and valence fluctuators are well reproduced by the transport coefficients computed for the PAM at low and high temperature. Finally, results obtained from first principles calculations are shown, after a short introduction to density functional theory and beyond. A number of useful appendices complete the book.

Download or read book Thermoelectric Thin Films written by Paolo Mele and published by Springer. This book was released on 2019-07-17 with total page 211 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will provide readers with deep insight into the intriguing science of thermoelectric thin films. It serves as a fundamental information source on the techniques and methodologies involved in thermoelectric thin film growth, characterization and device processing. This book involves widespread contributions on several categories of thermoelectric thin films: oxides, chalcogenides, iodates, nitrides and polymers. This will serve as an invaluable resource for experts to consolidate their knowledge and will provide insight and inspiration to beginners wishing to learn about thermoelectric thin films. Provides a single-source reference on a wide spectrum of topics related to thermoelectric thin films, from organic chemistry to devices, from physical chemistry to applied physics, from synthesis to device implementation; Covers several categories of thermoelectric thin films based on different material approaches such as oxides, chalcogenides, iodates, nitrides and polymers; Discusses synthesis, characterization, and device processing of thermoelectric thin films, as well as the nanoengineering approach to tailor the properties of the used materials at the nanoscale level.

Download or read book Thermoelectric Energy Conversion written by Ryoji Funahashi and published by Woodhead Publishing. This book was released on 2021-02-05 with total page 730 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermoelectric Energy Conversion: Theories and Mechanisms, Materials, Devices, and Applications provides readers with foundational knowledge on key aspects of thermoelectric conversion and reviews future prospects. Sections cover the basic theories and mechanisms of thermoelectric physics, the chemical and physical aspects of classical to brand-new materials, measurement techniques of thermoelectric conversion properties from the materials to modules and current research, including the physics, crystallography and chemistry aspects of processing to produce thermoelectric devices. Finally, the book discusses thermoelectric conversion applications, including cooling, generation, energy harvesting, space, sensor and other emerging areas of applications. Reviews key applications of thermoelectric energy conversion, including cooling, power generation, energy harvesting, and applications for space and sensing Discusses a wide range of materials, including skutterudites, heusler materials, chalcogenides, oxides, low dimensional materials, and organic materials Provides the fundamentals of thermoelectric energy conversion, including the physics, phonon conduction, electronic correlation, magneto-seebeck theories, topological insulators and thermionics

Download or read book New Materials for Thermoelectric Applications Theory and Experiment written by Veljko Zlatic and published by Springer. This book was released on 2012-10-17 with total page 283 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermoelectric devices could play an important role in making efficient use of our energy resources but their efficiency would need to be increased for their wide scale application. There is a multidisciplinary search for materials with an enhanced thermoelectric responses for use in such devices. This volume covers the latest ideas and developments in this research field, covering topics ranging from the fabrication and characterization of new materials, particularly those with strong electron correlation, use of nanostructured, layered materials and composites, through to theoretical work to gain a deeper understanding of thermoelectric behavior. It should be a useful guide and stimulus to all working in this very topical field.

Download or read book Quantum Transport in Mesoscopic Systems written by David Sánchez and published by MDPI. This book was released on 2021-01-06 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mesoscopic physics deals with systems larger than single atoms but small enough to retain their quantum properties. The possibility to create and manipulate conductors of the nanometer scale has given birth to a set of phenomena that have revolutionized physics: quantum Hall effects, persistent currents, weak localization, Coulomb blockade, etc. This Special Issue tackles the latest developments in the field. Contributors discuss time-dependent transport, quantum pumping, nanoscale heat engines and motors, molecular junctions, electron–electron correlations in confined systems, quantum thermo-electrics and current fluctuations. The works included herein represent an up-to-date account of exciting research with a broad impact in both fundamental and applied topics.