Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and transport properties of 2D transition metal carbides MXenes written by Joseph Halim and published by Linköping University Electronic Press. This book was released on 2018-09-28 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the isolation and characterization of graphene, there has been a growing interest in 2D materials owing to their unique properties compared to their 3D counterparts. Recently, a family of 2D materials of early transition metal carbides and nitrides, labelled MXenes, has been discovered (Ti2CTz, Ti3C2Tz, Mo2TiC2Tz, Ti3CNTz, Ta4C3Tz, Ti4N3Tz among many others), where T stands for surface-terminating groups (O, OH, and F). MXenes are mostly produced by selectively etching A layers (where A stands for group A elements, mostly groups 13 and 14) from the MAX phases. The latter are a family of layered ternary carbides and/or nitrides and have a general formula of Mn+1AXn (n = 1-3), where M is a transition metal and X is carbon and/or nitrogen. The produced MXenes have a conductive carbide core and a non-conductive O-, OH- and/or F-terminated surface, which allows them to work as electrodes for energy storage applications, such as Li-ion batteries and supercapacitors. Prior to this work, MXenes were produced in the form of flakes of lateral dimension of about 1 to 2 microns; such dimensions and form are not suitable for electronic characterization and applications. I have synthesized various MXenes (Ti3C2Tz, Ti2CTz and Nb2CTz) as epitaxial thin films, a more suitable form for electronic and photonic applications. These films were produced by HF, NH4HF2 or LiF + HCl etching of magnetron sputtered epitaxial Ti3AlC2, Ti2AlC, and Nb2AlC thin films. For transport properties of the Ti-based MXenes, Ti2CTz and Ti3C2Tz, changing n from 1 to 2 resulted in an increase in conductivity but had no effect on the transport mechanism (i.e. both Ti3C2Tx and Ti2CTx were metallic). In order to examine whether the electronic properties of MXenes differ when going from a few layers to a single flake, similar to graphene, the electrical characterization of a single Ti3C2Tz flake with a lateral size of about 10 μm was performed. These measurements, the first for MXene, demonstrated its metallic nature, along with determining the nature of the charge carriers and their mobility. This indicates that Ti3C2Tz is inherently of 2D nature independent of the number of stacked layers, unlike graphene, where the electronic properties change based on the number of stacked layers. Changing the transition metal from Ti to Nb, viz. comparing Ti2CTz and Nb2CTz thin films, the electronic properties and electronic conduction mechanism differ. Ti2CTz showed metallic-like behavior (resistivity increases with increasing temperature) unlike Nb2CTz where the conduction occurs via variable range hopping mechanism (VRH) - where resistivity decreases with increasing temperature. Furthermore, these studies show the synthesis of pure Mo2CTz in the form of single flakes and freestanding films made by filtering Mo2CTz colloidal suspensions. Electronic characterization of free-standing films made from delaminated Mo2CTz flakes was investigated, showing that a VRH mechanism prevails at low temperatures (7 to ≈ 60 K). Upon vacuum annealing, the room temperature, RT, conductivity of Mo2CTx increased by two orders of magnitude. The conduction mechanism was concluded to be VRH most likely dominated by hopping within each flake. Other Mo-based MXenes, Mo2TiC2Tz and Mo2Ti2C3Tz, showed VRH mechanism at low temperature. However, at higher temperatures up to RT, the transport mechanism was not clearly understood. Therefore, a part of this thesis was dedicated to further investigating the transport properties of Mo-based MXenes. This includes Mo2CTz, out-of-plane ordered Mo2TiC2Tz and Mo2Ti2C3Tz, and vacancy ordered Mo1.33CTz. Magneto-transport of free-standing thin films of the Mo-based MXenes were studied, showing that all Mo-based MXenes have two transport regimes: a VRH mechanism at lower temperatures and a thermally activated process at higher temperatures. All Mo-based MXenes except Mo1.33CTz show that the electrical transport is dominated by inter-flake transfer. As for Mo1.33CTz, the primary electrical transport mechanism is more likely to be intra-flake. The synthesis of vacancy ordered MXenes (Mo1.33CTz and W1.33CTz) raised the question of possible introduction of vacancies in all MXenes. Vacancy ordered MXenes are produced by selective etching of Al and (Sc or Y) atoms from the parent 3D MAX phases, such as (Mo2/3Sc1/3)2AlC, with in-plane chemical ordering of Mo and Sc. However, not all quaternary parent MAX phases form the in-plane chemical ordering of the two M metals; thus the synthesis of the vacancy-ordered MXenes is restricted to a very limited number of MAX phases. I present a new method to obtain MXene flakes with disordered vacancies that may be generalized to all quaternary MAX phases. As proof of concept, I chose Nb-C MXene, as this 2D material has shown promise in several applications, including energy storage, photothermal cell ablation and photocatalysts for hydrogen evolution. Starting from synthetizing (Nb2/3Sc1/3)2AlC quaternary solid solution and etching both the Sc and Al atoms resulted in Nb1.33C material with a large number of vacancies and vacancy clusters. This method may be applicable to other quaternary or higher MAX phases wherein one of the transition metals is more reactive than the other, and it could be of vital importance in applications such as catalysis and energy storage.
Download or read book Air Force Research Resum s written by and published by . This book was released on with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Introduction to Thin Films written by Leon I. Maissel and published by CRC Press. This book was released on 1973 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crystal and Epitaxial Growth written by V. Alexander Stefan, Editor and published by Stefan University Press. This book was released on 2002 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crystal Growth Bibliography written by and published by Springer Nature. This book was released on 1981 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics Briefs written by and published by . This book was released on 1991 with total page 1328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book MXenes and their Composites written by Kishor Kumar Sadasivuni and published by Elsevier. This book was released on 2021-10-07 with total page 796 pages. Available in PDF, EPUB and Kindle. Book excerpt: MXenes and their Composites: Synthesis, Properties and Potential Applications presents a state of the art overview of the recent developments on the synthesis, functionalization, properties and emerging applications of two-dimensional (2D) MXenes and their composites.The book systematically describes the state-of-the-art knowledge and fundamentals of MXene synthesis, structure, surface chemistry and functionalization. The book also discusses the unique electronic, optical, mechanical and topological properties of MXenes. Besides, this book covers the various emerging applications of MXenes and their composites across different fields such as energy storage and conversion, gas sensing and biosensing, rechargeable lithium and sodium-ion batteries, lithium-sulphur and multivalent batteries, electromagnetic interference shielding, hybrid capacitors and supercapacitors, hydrogen storage, catalysis and photoelectrocatalysis, gas separation and water desalination, environmental remediation and medical and biomedical applications. All these applications have been efficiently discussed in the specific chapters and in each case, the processing of MXene composites has also been discussed.This book will be an excellent reference for scientists and engineers across various disciplines and industries working in the field of highly promising 2D MXenes and their composites. The book will also act as a guide for academic researchers, material scientists, and advanced students in investigating the new applications of 2D MXenes based materials. - Covers fundamentals of technologically important MAX phases, MXene derivatives, MXene synthesis methods, intercalation and delamination strategies, surface functionalization, fundamental characteristics and properties - Demonstrates major application areas of MXenes, including catalytic, energy storage and energy generation, flexible electronics, EMI shielding, sensors and biosensors, medical and biomedical, gas separation and water desalination - Presents a detailed discussion on the processing and performance of various MXenes towards different applications
Download or read book Proceedings of the Symposium on Recent Advances in the Chemistry and Physics of Fullerenes and Related Materials written by Karl M. Kadish and published by The Electrochemical Society. This book was released on 1997 with total page 1274 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermodynamic Properties of Inorganic Materials written by Bertrand Cheynet and published by Elsevier Publishing Company. This book was released on 1989 with total page 1648 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This book is a bibliographical database of articles on thermodynamical properties of inorganic compounds, gases, solutions, metals and alloys, published between 1970 and 1987. This reference source book compiles 25,846 references about more than 13,400 systems and should be particularly useful for people working in inorganic chemical engineering, metallurgy, and new materials processing."--Preface.
Download or read book III Nitride Electronic Devices written by and published by Academic Press. This book was released on 2019-10-18 with total page 542 pages. Available in PDF, EPUB and Kindle. Book excerpt: III-Nitride Electronic Devices, Volume 102, emphasizes two major technical areas advanced by this technology: radio frequency (RF) and power electronics applications. The range of topics covered by this book provides a basic understanding of materials, devices, circuits and applications while showing the future directions of this technology. Specific chapters cover Electronic properties of III-nitride materials and basics of III-nitride HEMT, Epitaxial growth of III-nitride electronic devices, III-nitride microwave power transistors, III-nitride millimeter wave transistors, III-nitride lateral transistor power switch, III-nitride vertical devices, Physics-Based Modeling, Thermal management in III-nitride HEMT, RF/Microwave applications of III-nitride transistor/wireless power transfer, and more. - Presents a complete review of III-Nitride electronic devices, from fundamental physics, to applications in two key technical areas – RF and power electronics - Outlines fundamentals, reviews state-of-the-art circuits and applications, and introduces current and emerging technologies - Written by a panel of academic and industry experts in each field
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1971 with total page 2174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 2D Metal Carbides and Nitrides MXenes written by Babak Anasori and published by Springer Nature. This book was released on 2019-10-30 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the rapidly expanding field of two-dimensional (2D) transition metal carbides and nitrides (MXenes). It covers fundamental knowledge on synthesis, structure, and properties of these new materials, and a description of their processing, scale-up and emerging applications. The ways in which the quickly expanding family of MXenes can outperform other novel nanomaterials in a variety of applications, spanning from energy storage and conversion to electronics; from water science to transportation; and in defense and medical applications, are discussed in detail.
Download or read book Graphene written by Viera Skakalova and published by Woodhead Publishing. This book was released on 2021-06-23 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt: Graphene: Properties, Preparation, Characterization and Devices, Second Edition, provides a comprehensive look at the methods used to prepare and analyze graphene. Since the first edition's publication, there have been many advances in the understanding of graphene, in particular, its key properties and most relevant applications. Updates to this new edition include chapters on liquid exfoliation production of graphene and scanning transmission electron microscopy of graphene. New sections cover graphene's thermal, optical, mechanical, chemical and biocompatibility, with special attention paid to transport properties, a main barrier to the realization of commercial applications. - Reviews the preparation and characterization of graphene, covering the latest advances in liquid exfoliation production and the scanning transmission electron microscopy of graphene - Includes a new section dedicated to the properties of graphene (thermal, transport, optical, mechanical, chemical) to reflect the latest understanding of this important material - Discusses the most relevant applications of graphene, such as biomedical, sensing, energy and electronic applications
Download or read book Ceramic Abstracts written by and published by . This book was released on 1998 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1048 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bell Laboratories Talks and Papers written by Bell Telephone Laboratories. Libraries and Information Systems Center and published by . This book was released on 1974 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:
