Synthesis and Characterization of Transition Metal Nitrides and Carbides for Catalysis and Electrochemistry Application

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (959 download)

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Book Synopsis Synthesis and Characterization of Transition Metal Nitrides and Carbides for Catalysis and Electrochemistry Application by : Sarah Metzke

Download or read book Synthesis and Characterization of Transition Metal Nitrides and Carbides for Catalysis and Electrochemistry Application written by Sarah Metzke and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: It was the goal of this work to explore two different synthesis pathways using green chemistry. The first part of this thesis is focusing on the use of the urea-glass route towards single phase manganese nitride and manganese nitride/oxide nano-composites embedded in carbon, while the second part of the thesis is focusing on the use of the “saccharide route” (namely cellulose, sucrose, glucose and lignin) towards metal (Ni0), metal alloy (Pd0.9Ni0.1, Pd0.5Ni0.5, Fe0.5Ni0.5, Cu0.5Ni0.5 and W0.15Ni0.85) and ternary carbide (Mn0.75Fe2.25C) nanoparticles embedded in carbon. In the interest of battery application, MnN0.43 nanoparticles surrounded by a graphitic shell and embedded in carbon with a high surface area (79 m^2/g) were synthesized, following a previously set route.The comparison of the material characteristics before and after the discharge showed no remarkable difference in terms of composition and just slight differences in the morphological point of view, meaning the particles are stable but agglomerate. The graphitic shell ...

The Chemistry of Transition Metal Carbides and Nitrides

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Publisher : Springer Science & Business Media
ISBN 13 : 9400915659
Total Pages : 565 pages
Book Rating : 4.4/5 (9 download)

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Book Synopsis The Chemistry of Transition Metal Carbides and Nitrides by : S.T. Oyama

Download or read book The Chemistry of Transition Metal Carbides and Nitrides written by S.T. Oyama and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 565 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book arose from a symposium titled 'Transition Metal Carbides and Nitrides: Preparation, Properties, and Reactivity' organized by Jae Sung Lee, Masatoshi Nagai and myself. The symposium was part of the 1995 Congress of Pacific Rim Chemical Societies, held in Honolulu, Hawaii between December 17-22, 1995. The meeting was the first major conference to exclusively address the theme of metal carbides and nitrides, and brought together many of the major researchers in the field. Over 50 scientists and engineers reported their latest findings in five sessions of presentations and discussions. The book closely follows the topics covered in the conference: Theory of bonding Structure and composition Catalytic properties Physical properties New methods of preparation Spectroscopy and microscopy The book is unique in its coverage. It provides a general introduction to the properties and nature of the materials, but also covers their latest applications in a wide variety of fields. It should thus be of interest to both experts and nonexperts in the fields of material science, solid-state chemistry, physics, ceramics engineering, and catalysis. The first chapter gives an overview, and many of the chapters provide summaries of advanced topics. All contributions were peer-reviewed.

Transition Metal Carbides and Nitrides (MXenes) Handbook

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Publisher : John Wiley & Sons
ISBN 13 : 1119869498
Total Pages : 788 pages
Book Rating : 4.1/5 (198 download)

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Book Synopsis Transition Metal Carbides and Nitrides (MXenes) Handbook by : Chuanfang Zhang

Download or read book Transition Metal Carbides and Nitrides (MXenes) Handbook written by Chuanfang Zhang and published by John Wiley & Sons. This book was released on 2024-07-23 with total page 788 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive overview of the synthesis of high-quality MXenes In Transition Metal Carbides and Nitrides (MXenes) Handbook: Synthesis, Processing, Properties and Applications, a team of esteemed researchers provides an expert review encompassing the fundamentals of precursor selection, MXene synthesis, characterizations, properties, processing, and applications. You’ll find detailed discussions of the selection of MXene members for specific applications, as along with summaries of the physical and chemical properties of MXenes, including electrical, mechanical, optical, electromechanical, electrochemical, and electromagnetic properties. The authors delve into both successful and unsuccessful synthesis examples, offering detailed explanations of various failures to facilitates a comprehensive understanding of the reasons behind unsuccessful syntheses. Additionally, they provide detailed examinations on the characterizations of MXenes, empowering readers to develop a sophisticated understanding of how to achieve optimal quality, flake size, oxidation states, and more. You’ll also find: A thorough review of common applications of MXenes, including electrochemical applications, electromagnetic interference shielding, communications devices, and more Comprehensive explorations of solution and non-solution processing of MXenes Practical discussions of the synthesis of high-quality MXene powders, colloidal solutions and flakes, including information about MXene precursors Fulsome treatments of MXene precursor selection and their impact on MXene quality Tailored to meet the needs of graduate students, researchers, and scientists in the areas of materials science, inorganic chemistry, and physical chemistry, the Transition Metal Carbides and Nitrides (MXenes) Handbook will also benefit biochemists and professionals working in drug delivery.

2D Metal Carbides and Nitrides (MXenes)

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Publisher : Springer Nature
ISBN 13 : 3030190269
Total Pages : 534 pages
Book Rating : 4.0/5 (31 download)

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Book Synopsis 2D Metal Carbides and Nitrides (MXenes) by : Babak Anasori

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 534 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.

Transition Metal Carbides and Nitrides

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Publisher : Elsevier
ISBN 13 : 032315722X
Total Pages : 296 pages
Book Rating : 4.3/5 (231 download)

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Book Synopsis Transition Metal Carbides and Nitrides by : Louis Toth

Download or read book Transition Metal Carbides and Nitrides written by Louis Toth and published by Elsevier. This book was released on 2014-04-11 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Refractory Materials, Volume 7: Transition Metal Carbides and Nitrides discusses the developments in transition metal carbide and nitride research. This volume is organized into nine chapters that emphasize the mechanical and superconducting properties of these compounds. The introductory chapters deal with the general properties, preparation techniques, characterization, crystal chemistry, phase relationships, and thermodynamics of transition metal carbides and nitrides. The following chapter highlights the mechanical properties of these compounds, such as elastic and plastic deformation, fracture, strengthening mechanisms, and hardness. The discussion then shifts to specific electrical and magnetic properties, including electrical resistivity, Hall coefficient, and magnetic susceptibility. A separate chapter is devoted to carbides and nitrides as superconductors. The concluding chapters explore certain theories that explain the mechanisms of band structure and bonding in carbides and nitrides. This volume is of great value to research workers in metallurgy, ceramics, physics, chemistry, and related fields, as well as to advanced students investigating problems concerning high temperature materials or interstitial compounds.

Synthesis of Two-Dimensional Transition Metal Nitrides

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ISBN 13 :
Total Pages : 330 pages
Book Rating : 4.:/5 (115 download)

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Book Synopsis Synthesis of Two-Dimensional Transition Metal Nitrides by : Patrick S. Urbankowski

Download or read book Synthesis of Two-Dimensional Transition Metal Nitrides written by Patrick S. Urbankowski and published by . This book was released on 2019 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: The family of two-dimensional (2D) materials 0̐Ư solids with high aspect ratios and thicknesses consisting of a few atomic layers 0̐Ư has grown far beyond graphene. 2D transition metal carbides, nitrides and carbonitrides, known as MXenes, are one of the latest additions to this family. This rapidly growing class of 2D materials finds applications in fields ranging from energy storage to electromagnetic interference shielding and transparent conductive coatings. However, while over twenty carbide MXenes have been synthesized, very few transition metal nitrides (TMNs), and no nitride MXenes, had previously been reported. Two-dimensional TMNs, including nitride MXenes, have several potential advantages over their carbide analogs. They theoretically have higher values of electrical conductivity than carbide MXenes, which has implications on outperforming carbides in electrochemical and other applications. Compared to carbides, they are superior candidates for promising plasmonic devices and spintronic devices that incorporate magnetic 2D materials. Although there are theoretically as many nitride MXenes as carbide MXenes predicted, synthesizing nitride MXenes and 2D TMNs in general faces several challenges. Synthesis methods that have produced over two dozen 2D carbides MXenes have failed to yield 2D TMNs. The major focus of this dissertation is investigating routes of synthesizing 2D TMNs including, but not limited to, selective etching of layered bulk metal nitride precursors. Three promising routes of synthesis are explored, and their electronic and magnetic properties of the synthesized materials are also characterized. Discovering how to synthesize 2D TMNs will remove the barrier between merely studying their theoretically predicted properties and finally applying these outstanding properties in devices for energy storage, spintronics and beyond.

Transition Metal Carbide and Nitride Nanoparticles with Noble Metal Shells as Enhanced Catalysts

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ISBN 13 :
Total Pages : 157 pages
Book Rating : 4.:/5 (11 download)

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Book Synopsis Transition Metal Carbide and Nitride Nanoparticles with Noble Metal Shells as Enhanced Catalysts by : Aaron R. Garg

Download or read book Transition Metal Carbide and Nitride Nanoparticles with Noble Metal Shells as Enhanced Catalysts written by Aaron R. Garg and published by . This book was released on 2018 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: Core-shell nanostructures represent a promising and versatile design platform for enhancing the performance of noble metal catalysts while reducing the cost. Early transition metal carbides (TMCs) and nitrides (TMNs) have been identified as ideal core materials for supporting noble metal shells owing to their earth-abundance, thermal and chemical stability, electrical conductivity, and their ability to bind strongly to noble metals while still being immiscible with them. Unfortunately, the formation of surface oxides or carbon on TMCs and TMNs presents a difficult synthetic challenge for the deposition of atomically thin, uniform noble metal layers. Recent advances have enabled the synthesis of TMC core nanoparticles with noble metal shells (denoted as NM/TMC), although applicability toward TMN cores has not been previously demonstrated. Furthermore, the complete properties of these unique materials are still unknown. This thesis conducts a detailed investigation of the synthesis, characterization, and catalytic performance of NM/TMC and NM/TMN core-shell nanoparticles to provide a comprehensive understanding of their material properties and the underlying phenomena. First, in-situ studies yielded insight into the mechanism behind the high temperature self-assembly of NM/TMC particles, indicating the presence of a metallic alloy phase preceding the formation of the core-shell structure upon insertion of carbon into the lattice. Next, the synthesis of NM/TMN nanoparticles was demonstrated via nitridation of a parent NM/TMC, and the structural and electronic properties of both core-shell materials were examined through in-situ X-ray absorption spectroscopy (XAS). The analysis revealed significant alterations to the electronic structure of the noble metal shell due to bonding interactions with the TMC and TMN cores, which led to weakened adsorbate binding energies. Finally, the materials displayed improved performance for the oxygen reduction reaction (ORR), a critical challenge for fuel cell technologies. Notably, particles with complete, uniform shells exhibited unprecedented stability during electrochemical ageing at highly oxidizing conditions, highlighting the great potential of core-shell architectures with earth-abundant TMC and TMN cores for future ORR applications. Overall, this work will provide new opportunities toward the design of enhanced noble metal catalysts and enable further optimization of their performance.

Rapid Microwave-assisted Synthesis and Characterization of Transition Metal Carbides and Nitrides

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (16 download)

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Book Synopsis Rapid Microwave-assisted Synthesis and Characterization of Transition Metal Carbides and Nitrides by : Giandomenico Furnari

Download or read book Rapid Microwave-assisted Synthesis and Characterization of Transition Metal Carbides and Nitrides written by Giandomenico Furnari and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Synthesis and Characterization of Intermetallic Compounds and Transition Metal Nitrides as High-performance Proton Exchange Membrane Fuel Cell Materials

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Publisher :
ISBN 13 :
Total Pages : 67 pages
Book Rating : 4.:/5 (9 download)

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Book Synopsis Synthesis and Characterization of Intermetallic Compounds and Transition Metal Nitrides as High-performance Proton Exchange Membrane Fuel Cell Materials by : Weitian Zhao

Download or read book Synthesis and Characterization of Intermetallic Compounds and Transition Metal Nitrides as High-performance Proton Exchange Membrane Fuel Cell Materials written by Weitian Zhao and published by . This book was released on 2014 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the major challenges in fuel cell technologies, particularly for Proton Exchange Membrane Fuel Cells (PEMFCs), is developing effective catalysts for use in both the anode and cathode. Ordered intermetallic compounds have shown considerable potential for fuel cell applications due to their enhanced catalytic activity, better durability and lower cost. In this work, Pd-Sn intermetallic compounds were investigated. PdSn and Pd3Sn nanoparticles were synthesized under air-free conditions and were tested for their electrochemical properties. Both materials showed poor activities in acidic environment for formic acid and methanol oxidation, but enhanced activities under basic conditions. Various electrochemical tests and structural characterization including high-resolution TEM/STEM and EDX were performed to investigate the changes in these materials that might have resulted in such performance. In this thesis, we also focus on developing stable catalyst supports for fuel cell electrodes, another topic in fuel cell research. Motivated by recent studies which revealed the potential of transition metal nitrides as high performance catalyst supports, we developed a facile synthesis of single-phase, nanocrystalline macroporous chromium nitride and chromium titanium (oxy)nitride with an inverse opal morphology. Characterization using XRD, SEM, HR-TEM/STEM, TGA and XPS is reported. Interconversion of macroporous CrN to Cr2O3 and back to CrN while retaining the inverse opal morphology was also demonstrated. iii.

Synthesis and Characterization of Transition-metal Nanocrystals and Their Application in Catalysis

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ISBN 13 :
Total Pages : 488 pages
Book Rating : 4.:/5 (68 download)

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Book Synopsis Synthesis and Characterization of Transition-metal Nanocrystals and Their Application in Catalysis by : Guangjun Cheng

Download or read book Synthesis and Characterization of Transition-metal Nanocrystals and Their Application in Catalysis written by Guangjun Cheng and published by . This book was released on 2003 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Materials for Energy Storage

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Publisher : CRC Press
ISBN 13 : 1040096778
Total Pages : 319 pages
Book Rating : 4.0/5 (4 download)

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Book Synopsis Materials for Energy Storage by : Niroj Kumar Sahu

Download or read book Materials for Energy Storage written by Niroj Kumar Sahu and published by CRC Press. This book was released on 2024-07-26 with total page 319 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials for Energy Storage offers a combinatorial understanding of materials science and electrochemistry in electrochemical energy storage devices with a holistic overview of the status, research gaps, and future opportunities. Rooted in a profound understanding of contemporary energy utilization, aligned with the sustainable development goals, this book delves deep into the several device chemistries, impact of nanomaterials, and critical factors related to the device performance. It discusses electrode-electrolyte interaction, device fabrication, and commercial aspects. This book will offer value to the graduate and postgraduate students, researchers, and industry professionals related to materials science and energy technology.

Synthesis and Characterization of Transition Metal Nitride Materials

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Publisher :
ISBN 13 :
Total Pages : 412 pages
Book Rating : 4.:/5 (477 download)

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Book Synopsis Synthesis and Characterization of Transition Metal Nitride Materials by : Shalawn Kirkland Jackson

Download or read book Synthesis and Characterization of Transition Metal Nitride Materials written by Shalawn Kirkland Jackson and published by . This book was released on 2001 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:

A Neglected World

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (935 download)

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Book Synopsis A Neglected World by : Cristina Giordano

Download or read book A Neglected World written by Cristina Giordano and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Potentiality of nanosized materials has been largely proved but a closer look shows that a significant percentage of this research is related to oxides and metals, while the number drastically drops for metallic ceramics, namely transition metal nitrides and metal carbides. The lack of related publications do not reflect their potential but rather the difficulties related to their synthesis as dense and defect-free structures, fundamental prerequisites for advanced mechanical applications. The present habilitation work aims to close the gap between preparation and processing, indicating novel synthetic pathways for a simpler and sustainable synthesis of transition metal nitride (MN) and carbide (MC) based nanostructures and easier processing thereafter. In spite of simplicity and reliability, the designed synthetic processes allow the production of functional materials, with the demanded size and morphology. The goal was achieved exploiting classical and less-classical precursors, ranging from common metal salts and molecules (e.g. urea, gelatin, agar, etc), to more exotic materials, such as leafs, filter paper and even wood. It was found that the choice of precursors and reaction conditions makes it possible to control chemical composition (going for instance from metal oxides to metal oxy-nitrides to metal nitrides, or from metal nitrides to metal carbides, up to quaternary systems), size (from 5 to 50 nm) and morphology (going from mere spherical nanoparticles to rod-like shapes, fibers, layers, meso-porous and hierarchical structures, etc). The nature of the mixed precursors also allows the preparation of metal nitrides/carbides based nanocomposites, thus leading to multifunctional materials (e.g. MN/MC@C, MN/MC@PILs, etc) but also allowing dispersion in liquid media. Control over composition, size and morphology is obtained with simple adjustment of the main route, but also coupling it with processes such as electrospin, aerosol spray, bio-templating, etc. Last but not least, the nature of the precursor materials also allows easy processing, including printing, coating, casting, film and thin layers preparation, etc). The designed routes are, concept-wise, similar and they all start by building up a secondary metal ion-N/C precursor network, which converts, upon heat treatment, into an intermediate "glass". This glass stabilizes the nascent nanoparticles during their nucleation and impairs their uncontrolled growth during the heat treatment (scheme 1). This way, one of the main problems related to the synthesis of MN/MC, i.e. the need of very high temperature, could also be overcome (from up to 2000°C, for classical synthesis, down to 700°C in the present cases). The designed synthetic pathways are also conceived to allow usage of non-toxic compounds and to minimize (or even avoid) post-synthesis purification, still bringing to phase pure and well-defined (crystalline) nanoparticles. This research aids to simplify the preparation of MN/MC, making these systems now readily available in suitable amounts both for fundamental and applied science. The prepared systems have been tested (in some cases for the first time) in many different fields, e.g. battery (MnN0.43@C shown a capacity stabilized at a value of 230 mAh/g, with coulombic efficiencies close to 100%), as alternative magnetic materials (Fe3C nanoparticles were prepared with different size and therefore different magnetic behavior, superparamagnetic or ferromagnetic, showing a saturation magnetization value up to 130 emu/g, i.e. similar to the value expected for the bulk material), as filters and for the degradation of organic dyes (outmatching the performance of carbon), as catalysts (both as active phase but also as active support, leading to high turnover rate and, more interesting, to tunable selectivity). Furthermore, with this route, it was possible to prepare for the first time, to the best of our knowledge, well-defined and crystalline MnN0.43, Fe3C and Zn1.7GeN1.8O nanoparticles via bottom-up approaches. Once the synthesis of these materials can be made straightforward, any further modification, combination, manipulation, is in principle possible and new systems can be purposely conceived (e.g. hybrids, nanocomposites, ferrofluids, etc).zeige weniger

Theoretical and Experimental Studies on Early Transition Metal Nitrides for Thermoelectrics

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Publisher : Linköping University Electronic Press
ISBN 13 : 9179299644
Total Pages : 56 pages
Book Rating : 4.1/5 (792 download)

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Book Synopsis Theoretical and Experimental Studies on Early Transition Metal Nitrides for Thermoelectrics by : Mohammad Amin Gharavi

Download or read book Theoretical and Experimental Studies on Early Transition Metal Nitrides for Thermoelectrics written by Mohammad Amin Gharavi and published by Linköping University Electronic Press. This book was released on 2019-11-18 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermoelectricity transforms temperature gradients across thermoelectric material into an external voltage through a phenomenon known as the Seebeck effect. This property has resulted in niche applications such as solid-state cooling for electronic and optoelectronic devices which exclude the need for a coolant or any moving parts and long-lasting, maintenance-free radioisotope thermoelectric generators used for deep-space exploration. However, the high price and low efficiency of thermoelectric generators have prompted scientists to search for new materials and/or methods to improve the efficiency of the already existing ones. Thermoelectric efficiency is governed by the dimensionless figure of merit ????, which depends on the electrical conductivity, thermal conductivity and Seebeck coefficient value of the material and has rarely surpassed unity. In order to address these issues, research conducted on early transition metal nitrides spearheaded by cubic scandium nitride (ScN) thin films showed promising results with high power factors close to 3000 ?Wm?1K?2 at 500 °C. These results are the main motivation behind my thesis where the conducted research is separated into two different routes: • the synthesis and characterization of chromium nitride thin films and its alloys • the study of hypothetical ternary nitrides equivalent to scandium nitride Rock-salt cubic chromium nitride (CrN) deposited in the form of thin films by reactive magnetron sputtering was chosen for its large Seebeck coefficient of approximately -200 ?V/K and low thermal conductivity between 2 and 4 Wm?1K?1. The results show that CrN in single crystal form has a low electrical resistivity below 1 m?cm, a Seebeck coefficient value of -230 ?V/K and a power factor close to 5000 ?Wm?1K?2 at room temperature. These promising results could lead to CrN based thermoelectric modules which are cheaper and more stable compared to traditional thermoelectric material such as bismuth telluride (Bi2Te3) and lead telluride (PbTe). Although cubic CrN has been shown to be a promising material for research with a large power factor, the electrical resistivity limits applications in pure form as the ???? is estimated to be slightly below 0.5. To overcome this issue, I enhanced the thermoelectric power-factor of CrN by alloying it with a conductor, Rock-salt cubic vanadium nitride (VN). VN is a suitable choice as both materials share the same crystal structure and have almost equal lattice constants. Through deposition at 720 °C, where a small amount of VN (less than 5%) and Cr2N is introduced into the film, a reduced electrical resistivity averaged around 0.8 × 10-3 ?cm, Seebeck coefficient value of 270 ?V/K and a power-factor of 9.1 × 10-3 W/mK2 is measured at room temperature, which surpasses the thermoelectric properties of Bi2Te3. Hexagonal dichromium nitride (Cr2N) nano-inclusions increase the charge carrier concentration and act as phonon scattering sites. Single crystal Cr2N was also studied separately, as it shows interesting elastic-plastic mechanical properties and high resistance to oxidation at high temperatures for long periods of time. In the second part of this thesis, hypothetical ternary nitrides equivalent to ScN are investigated for their prospective thermoelectric properties. Scandium nitride has a relatively high thermal conductivity value (close to 10 Wm?1K?1), resulting in a low ????. A hypothetical ternary equivalent to ScN may have a similar electronic band structure and large power factor, but with a lower thermal conductivity value leading to better thermoelectric properties. Thus, the elements magnesium, titanium, zirconium, and hafnium were chosen for this purpose. DFT calculations were used to simulate TiMgN2, ZrMgN2 and HfMgN2. The results show the MeMgN2 stoichiometry to be stable, with two rivaling crystal structures: trigonal NaCrS2 and monoclinic LiUN2. The calculated electronic band structure of these compounds shows a direct band-gap for the monoclinic and an indirect band-gap for the trigonal crystal structures. These findings, coupled with predicted Seebeck coefficient values, encourages actual synthesis of such materials. DFT calculations were also used to study (Zr, Mg)N and (Hf, Mg)N alloys based on the SQS model. The transition temperature between the ordered monoclinic structure of ZrMgN2 and HfMgN2 and the disordered (Zr, Mg)N and (Hf, Mg)N alloys is calculated to be approximately 800 K and 1050 K respectively. Density of State (DoS) calculations show that similar to (Ti, Mg)N, (Zr, Mg)N and (Hf, Mg)N are also semiconducting. The thermoelectric properties of both compounds are also predicted, and that in the range of a moderate change in the Fermi level, high Seebeck coefficient values at room temperature can be achieved. Finally, in order to complete the mentioned study on hypothetical ternaries, I deposited (Ti, Mg)N thin film alloys by reactive magnetron sputtering. These films, which were deposited at 400 °C, are porous and are crystallized in the rocksalt cubic structure. As-deposited films show an electrical resistivity of 150 m?cm and a Seebeck coefficient of -25 ?V/K, which shows semiconducting properties. In order to initiate a phase transformation, these films when annealed at approximately 800 °C, where nano-inclusions of a titanium/magnesium oxynitride are formed in a LiTiO2-type superstructure are identified by XRD and TEM analysis.

Mechanism and Kinetics of 2D Transition Metal Carbides (MXenes) Synthesis

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (14 download)

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Book Synopsis Mechanism and Kinetics of 2D Transition Metal Carbides (MXenes) Synthesis by : Mark Anayee

Download or read book Mechanism and Kinetics of 2D Transition Metal Carbides (MXenes) Synthesis written by Mark Anayee and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two-dimensional (2D) nanomaterials including graphene, hexagonal boron nitride (h-BN), transition metal dichalcogenides (TMDs), and MXenes have attracted much attention because they present a wide range of physicochemical, optoelectronic, and mechanical properties along with various atomic structures and compositions. MXenes represent the largest and rapidly growing family of 2D transition metal carbides and/or nitrides, which exhibit unique combinations of properties, including metallic conductivity, hydrophilic surface chemistry, redox-active surface, and plasmonic behavior that make them attractive as electrodes for pseudocapacitive energy storage to coatings for electromagnetic interference shielding, transparent conducting displays for optoelectronics, conductive yarns for functional textiles, implantable electrodes for medicine, and many other applications. MXenes are typically derived via topochemical etching of atomically thick layers from precursor layered MAX phases using corrosive aqueous etchants. However, the chemical etching process is only somewhat optimized for one composition, and is nonetheless often slow, with low-yield, and results in defects in the materials.

The Synthesis and Characterization of Nitrides and Other Non-oxide Materials

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ISBN 13 :
Total Pages : 896 pages
Book Rating : 4.E/5 ( download)

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Book Synopsis The Synthesis and Characterization of Nitrides and Other Non-oxide Materials by : Mark Stuart Bailey

Download or read book The Synthesis and Characterization of Nitrides and Other Non-oxide Materials written by Mark Stuart Bailey and published by . This book was released on 2005 with total page 896 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Synthesis and Characterization of New Transition - Metal Nitrides

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (16 download)

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Book Synopsis Synthesis and Characterization of New Transition - Metal Nitrides by : Lev A. Sviridov

Download or read book Synthesis and Characterization of New Transition - Metal Nitrides written by Lev A. Sviridov and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: