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:

Download or read book Synthesis and Characterization of Transition Metal Based Metal Oxide and Metallic Nanocrystals for AC Magnetic Devices and Catalysis written by Hongseok Yun and published by . This book was released on 2015 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: The d-block elements are very important in magnetics, electronics, catalysis, and biological systems. The synthesis and characterization of nearly monodisperse d-block element based nanocrystals with a precise control over the size, composition, and shape are important to utilize the nanocrystals in such applications. The goals of my thesis are to synthesize d-block transition metal based nanocrystals and understand their magnetic and catalytic properties. I present the size- and composition-dependent AC magnetic permeability of superparamagnetic iron oxide nanocrystals for radio frequency applications. The nanocrystals are synthesized through high-temperature solvothermal decomposition, and their stoichiometry is determined by Mössbauer spectroscopy. Size-dependent magnetic permeability is observed in maghemite nanocrystals, while as-synthesized, magnetite-rich, iron oxide nanocrystals do not show size dependence due to the inhomogeneous crystal structure of the as-synthesized nanocrystals. The saturation magnetization of iron oxide nanocrystals is increased by doping of non-magnetic Zn2+ into A site of ferrite, resulting the enhancement of the real part of the magnetic permeability of Zn0.25Fe2.75O4 nanocrystals by twofold compared to that of similarly sized ferrite nanocrystals. The integration of 12.3 nm Zn0.25Fe2.75O4 nanocrystals into a microfabricated toroidal inductor and a solenoid inductor yield higher quality factors than air core inductors with the same geometries. The ligand exchange with dendrimers reduces the blocking temperature of Mn0.08Zn0.33Fe2.59O4 nanocrystal, indicating the decrease of dipolar coupling between nanocrystals. The study on MnxFe3-xO4 and CoxFe3-xO4 nanocrystals shows a clear difference in DC and AC magnetic behaviors of soft and hard magnetic nanocrystals. The inductor with zinc ferrite nanocrystal core is embedded into a power converter and its temperature dependent energy efficiency is measured. The energy efficiency of a power converter with the nanocrystal core inductor rises as the temperature increases while that of the power converters with an air core inductor or commercial core inductor decreases. Finally, I describe the hydrodeoxygenation reaction of 5-hydroxymethylfurfural into 2,5-dimethylfuran by metallic nanocrystals such as Pt, PtMn, PtFe, PtCo, and PtNi. Both conversion ratio and selectivity for 2,5-dimethylfuran show clear composition dependent catalytic properties and, in particular, 3.7 nm Pt3Co2 nanocrystals achieve 98 % of selectivity for 2,5-dimethylfuran.

Download or read book Metal Nanocrystals written by Kallum M. Koczkur and published by American Chemical Society. This book was released on 2020-07-31 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our society depends heavily on metals. They are ubiquitous construction materials, critical interconnects in integrated circuits, common coinage materials, and more. Excitingly, new uses for metals are emerging with the advent of nanoscience, as metal crystals with nanoscale dimensions can display new and tunable properties. The optical and photothermal properties of metal nanocrystals have led to cancer diagnosis and treatment platforms now in clinical trials, while, at the same time, the ability to tune the surface features of metal nanocrystals is giving rise to designer catalysts that enable more sustainable use of precious resources. These are just two examples of how metal nanocrystals are addressing important social needs.

Download or read book Functional Nanometer Sized Clusters of Transition Metals written by Wei Chen and published by Royal Society of Chemistry. This book was released on 2014-08-14 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal nanoclusters, which bridge metal atoms and nanocrystals, are gaining attention due to their unique chemical and physical properties which differ greatly from their corresponding large nanoparticles and molecular compounds. Their electronic and optical properties are of particular interest for their use in sensing, optoelectronics, photovoltaics and catalysis. The book highlights recent progress and challenges in size-controlled synthesis, size-dependent properties, characterization and applications of metal nanoclusters. Specific topics include organochalcogenolate-stabilized metal nanoparticles, water-soluble fluorescent silver nanoclusters, thiolate-protected Au and Ag nanoclusters, DNA-templated metal nanoclusters, fluorescent platinum nanoclusters and janus nanoparticles by interfacial engineering. Edited by active researchers in the area, the book provides a valuable reference for researchers in the area of functional nanomaterials. It also provides a guide for graduate students, academic and industrial researchers interested in the fundamentals of the materials or their applications.

Download or read book Nanoparticles in Catalysis written by Karine Philippot and published by John Wiley & Sons. This book was released on 2021-03-16 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanoparticles in Catalysis Discover an essential overview of recent advances and trends in nanoparticle catalysis Catalysis in the presence of metal nanoparticles is an important and rapidly developing research field at the frontier of homogeneous and heterogeneous catalysis. In Nanoparticles in Catalysis, accomplished chemists and authors Karine Philippot and Alain Roucoux deliver a comprehensive guide to the key aspects of nanoparticle catalysis, ranging from synthesis, activation methodology, characterization, and theoretical modeling, to application in important catalytic reactions, like hydrogen production and biomass conversion. The book offers readers a review of modern and efficient tools for the synthesis of nanoparticles in solution or onto supports. It emphasizes the application of metal nanoparticles in important catalytic reactions and includes chapters on activation methodology and supported nanoclusters. Written by an international team of leading voices in the field, Nanoparticles in Catalysis is an indispensable resource for researchers and professionals in academia and industry alike. Readers will also benefit from the inclusion of: A thorough introduction to New Trends in the Design of Metal Nanoparticles and Derived Nanomaterials for Catalysis An exploration of Dynamic Catalysis and the Interface Between Molecular and Heterogeneous Catalysts A practical discussion of Metal Nanoparticles in Water: A Relevant Toolbox for Green Catalysis Organometallic Metal Nanoparticles for Catalysis A concise treatment of the opportunities and challenges of CO2 Hydrogenation to Oxygenated Chemicals Over Supported Nanoparticle Catalysts Perfect for catalytic, organic, inorganic, and physical chemists, Nanoparticles in Catalysis will also earn a place in the libraries of chemists working with organometallics and materials scientists seeking a one-stop resource with expert knowledge on the synthesis and characterization of nanoparticle catalysis.

Download or read book Metal Nanoparticles for Catalysis written by Franklin Tao and published by Royal Society of Chemistry. This book was released on 2014-06-12 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalysis is a central topic in chemical transformation and energy conversion. Thanks to the spectacular achievements of colloidal chemistry and the synthesis of nanomaterials over the last two decades, there have also been significant advances in nanoparticle catalysis. Catalysis on different metal nanostructures with well-defined structures and composition has been extensively studied. Metal nanocrystals synthesized with colloidal chemistry exhibit different catalytic performances in contrast to metal nanoparticles prepared with impregnation or deposition precipitation. Additionally, theoretical approaches in predicting catalysis performance and understanding catalytic mechanism on these metal nanocatalysts have made significant progress. Metal Nanoparticles for Catalysis is a comprehensive text on catalysis on Nanoparticles, looking at both their synthesis and applications. Chapter topics include nanoreactor catalysis; Pd nanoparticles in C-C coupling reactions; metal salt-based gold nanocatalysts; theoretical insights into metal nanocatalysts; and nanoparticle mediated clock reaction. This book bridges the gap between nanomaterials synthesis and characterization, and catalysis. As such, this text will be a valuable resource for postgraduate students and researchers in these exciting fields.

Download or read book Design Synthesis and Characterization of Transition Metal Oxide Nanomaterials for Emerging Catalytic Applications written by Dharmarathna Arachchige Saminda Dharmarathna and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Nanoparticles and Catalysis written by Didier Astruc and published by John Wiley & Sons. This book was released on 2008-06-25 with total page 663 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by international experts, this monograph combines two of the most important aspects of modern chemistry, presenting the latest knowledge on these environmental friendly applications. This result is a comprehensive overview of the application of nanoparticles in catalysis, focusing on synthesis and the most important reaction types, providing all the information needed by catalytic, organic and solid state chemists, as well as those working with or on organometallics, materials scientists, and chemists in industry.

Download or read book Nanomaterials in Catalysis written by Philippe Serp and published by John Wiley & Sons. This book was released on 2012-11-15 with total page 741 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanocatalysis has emerged as a field at the interface between homogeneous and heterogeneous catalysis and offers unique solutions to the demanding requirements for catalyst improvement. Heterogeneous catalysis represents one of the oldest commercial applications of nanoscience and nanoparticles of metals, semiconductors, oxides, and other compounds have been widely used for important chemical reactions. The main focus of this fi eld is the development of well-defined catalysts, which may include both metal nanoparticles and a nanomaterial as the support. These nanocatalysts should display the benefits of both homogenous and heterogeneous catalysts, such as high efficiency and selectivity, stability and easy recovery/recycling. The concept of nanocatalysis is outlined in this book and, in particular, it provides a comprehensive overview of the science of colloidal nanoparticles. A broad range of topics, from the fundamentals to applications in catalysis, are covered, without excluding micelles, nanoparticles in ionic liquids, dendrimers, nanotubes, and nanooxides, as well as modeling, and the characterization of nanocatalysts, making it an indispensable reference for both researchers at universities and professionals in industry.

Download or read book Synthesis and Characterization of Transition Metal Nitride and Selenide Nanocrystals and Heterostructures written by Robert William Lord and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The properties of nanomaterials are intimately dependent on their size, morphology, composition both elemental and structural, as well as their crystal structure or atomic arrangement. There exists a fundamental need to develop methods to precisely control and tune these parameters in order to target desirable materials. Colloidal chemistries utilize wet chemical precursors to synthesize inorganic nanomaterials from the bottom up and produce high quality materials. In addition to single component material synthesis, colloidal chemistries have been developed to synthesize multicomponent nanomaterials systems through a process called seeded growth. Seeded growth utilizes preformed nanoparticles as substrates to nucleate and grow new materials from their surfaces. This has led to the synthesis of highly complex heterostructured nanoparticles which allow for the incorporation of multiple material properties within single particle frameworks. While these techniques can control the structure and composition of the synthesized material, they do not allow for as much control over the resulting crystal structure. Other methods have been developed which allow for crystallographic templating and compositional modulation by post-synthetic cation exchange. Cation exchange utilizes molecular agents to solvate and exchange host cations in preformed crystals with those in solution while maintaining the anion sublattice relatively unperturbed. The crystallographic symmetry of the anion sublattice determines the symmetry of the final product phase. As such, cation exchange has allowed researchers to synthesize materials which are either metastable in bulk or not easily assessable through other methods. In this dissertation I discuss my efforts to utilize these synthetic tools to synthesize new and complex inorganic nanoparticles. First, I describe the seeded growth of Cu3N and Cu3PdN on Pt and Au nanocrystals. Utilizing Pt-Cu3PdN as the model system, it was observed that Cu3PdN nucleated and grew in a step-wise pathway with the initial deposition of Cu onto the surface. This was followed by the deposition of Pd onto the corners and edges of the Pt nanocubes which was followed by the coalescence and crystallization of Cu with the Pd to ultimately give Cu3PdN. When nucleating on more faceted or spherical seeds, whether Pt or Au, the resulting heterostructures took on more core@shell structures. In the absence of Pd, Cu3N nucleates indiscriminately on the surface of Pt without any of the regioselectivity seen with Cu3PdN. When utilizing Au seeds, AuCu alloy formation is observed without any apparent heterostructure formation. These observations helped us develop guidelines which are anticipated to be applicable to the formation of other ternary nitride heterostructures. Second, I discuss the synthesis of a new, metastable phase of copper selenide nanoparticles. This material was shown by EDS and XPS to adopt a nominally 2:1 stoichiometry and the XRD pattern did not match any known phase of Cu2-xSe. However, the nanoparticles did adopt a crystal structure similar to previously observed weissite Cu2-xTe. A structural model for our Cu2-xSe phase was developed utilizing a recently reported structural model for weissite Cu2-xTe which was computationally verified in collaboration with Professor Ismaila Dabo's group. Weissite-like Cu2-xSe has trigonal symmetry (space group P ̄3 m1) and is a layered structure with alternative Cu-rich and Cu-deficient layers sandwiched between layers of Se. UV-vis-NIR spectroscopy of weissite-like Cu2-xSe showed a broad plasmon absorbance band centered around 1550 nm. Lastly, I discuss my efforts to develop synthetic guidelines for the competitive synthesis of ternary copper selenide phases during their nucleation on Pt nanoparticle seeds. We showed experiments which allude to two potential synthetic pathways for the formation of CuFeSe2 and CuInSe2. It was observed that the CuInSe2 forms through a multistep pathway starting with the initial nucleation of Cu2-xSe followed by the incorporation of the In3+ through a high temperature cation exchange reaction. However, CuFeSe2 was shown to most likely to form by direct nucleation. The differences in these reactions were observed when their simultaneous nucleation was attempted, where only Pt--CuIn¬Se2 formed.

Download or read book Design Synthesis and Characterization of Transition Metal Oxide Based Functional Materials for Multi phase Catalytic Applications written by and published by . This book was released on 2015 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metastable Phase Materials written by Qi Shao and published by John Wiley & Sons. This book was released on 2024-08-26 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes an arising branch of materials, metastable materials, which are rarely discussed before and addresses their applications in catalytic reactions.

Download or read book Carbon Supported Transition Metal Nanoparticles for Catalytic and Electromagnetic Applications written by and published by . This book was released on 2018 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently, there has been growing interest in using transition metals (TM) for catalytic and electromagnetic applications, due to the ability of TMs to form stable compounds in multiple oxidation states. In this research, the focus has been on the synthesis and characterization of carbon-supported TM nanoparticles (NPs), specifically palladium (Pd) and gold (Au) NPs, for catalytic applications, and transition metal oxides (TMO) NPs, specifically Fe3O4 NPs for electromagnetic applications. Carbon supports have several advantages, such as enabling even distribution of particles, offering large specific surface area with excellent electron conductivity, and relative chemical inertness. In this dissertation, for catalytic applications, emphasis was on removal of trichloroethylene (TCE) from groundwater. For this application, carbon-supported Pd/Au NP catalysts were developed. Pd was chosen because it is more active, stable and selective for desired end-products, and Au has shown to be a good promotor of Pd's catalytic activity. Often, commercially available Pd-based catalysts are made using harsh chemicals, which can be harmful to the environment. Here, an environmentally friendly process with aspects of green chemistry was developed to produce carbon-supported Pd/Au NP catalysts. This process uses a combination of sonochemistry and solvothermal syntheses. The carefully designed carbon-supported Pd/Au NP catalyst material was systematically characterized, tested against TCE, and optimized for increased rate of removal of TCE. Electron microscopy and spectroscopy techniques were used to study the material including structure, configuration and oxidative state. The Pd/Au NPs were found mainly to form clusters with an aggregate-PdShellAuCore structure. Using state-of-the-art direct detection with electron energy loss spectroscopy, the Pd NPs were found to have an oxidative state of zero (0). The formation of the catalyst material was studied in detail by varying several synthesis parameters including type of solvent, sonication time, synthesis temperature etc. The most optimized catalyst was found remove TCE at double the rate of corresponding commercial Pd-based catalysts in a hydrogen headspace. This material was found to catalyze the removal of TCE via traditional hydrodehalogenation and shows promise for the removal of other contaminants such as trichloropropane (TCP), carbon tetrachloride (CT). The focus of this dissertation was on the development of a methodology for carbon-supported TM and TMO NPs for specific applications. It is envisioned that this approach and strategy will contribute towards the future optimization of similar material systems for a multitude of applications.

Download or read book Design Synthesis and Characterization of Transition Metal Oxide Nanomaterials as Efficient Sorbents and Multifunctional Catalysts for Oxidation Dehydrogenative Coupling and Desulfurization Reactions written by Chandima Weerakkody and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The research work presented here is focused on nanotechnological synthetic approaches for transition metal oxide nanomaterials and their applications in heterogeneous catalysis and adsorptive desulfurization reactions. Here, we discuss the controllable synthesis of functional nanomaterials and investigation of their structure-activity relationship in multiphase catalytic and sorption reactions. Among transition metal oxides, Co3O4 is well known for the presence of mobile oxygen, and thus is more reactive towards oxidation reactions. Aerobic oxidation under additive free conditions is highly desirable in organic synthesis reactions, from the viewpoint of green and sustainable chemistry. We demonstrate the activity enhancement of mesoporous cobalt oxide materials by substitutional doping of molybdenum ions. We discuss the surface chemistry in the production of active metal oxide nanoparticles and effect of lattice deformation on creating surface defects. High conversion and selectivity was achieved by controlling the surface area, Lewis acidity, and oxygen vacancy density of the solid catalyst in the liquid phase dehydrogenative coupling reactions. Synthesis of high surface area mesoporous cobalt molybdenum mixed metal oxide materials was accomplished using surfactant assisted inverse micelle method. The cobalt molybdenum oxide materials were investigated as a efficient desulfurization sorbent in a fixed bed reactor at low temperatures ( C).

Download or read book Synthesis and Characterization of 2D Nanocrystals and Thin Films of Transition Metal Carbides MXenes written by and published by . This book was released on 2014 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Nanomaterials for Catalysis and Energy written by Vladislav A. Sadykov and published by Elsevier. This book was released on 2018-08-27 with total page 587 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced Nanomaterials for Catalysis and Energy: Synthesis, Characterization and Applications outlines new approaches to the synthesis of nanomaterials (synthesis in flow conditions, laser electrodispersion of single metals or alloys on carbon or oxide supports, mechanochemistry, sol-gel routes, etc.) to provide systems with a narrow particle size distribution, controlled metal-support interaction and nanocomposites with uniform spatial distribution of domains of different phases, even in dense sintered materials. Methods for characterization of real structure and surface properties of nanomaterials are discussed, including synchrotron radiation diffraction and X-ray photoelectron spectroscopy studies, neutronography, transmission/scanning electron microscopy with elemental analysis, and more. The book covers the effect of nanosystems' composition, bulk and surface properties, metal-support interaction, particle size and morphology, deposition density, etc. on their functional properties (transport features, catalytic activity and reaction mechanism). Finally, it includes examples of various developed nanostructured solid electrolytes and mixed ionic-electronic conductors as materials in solid oxide fuel cells and asymmetric supported membranes for oxygen and hydrogen separation. Outlines synthetic and characterization methods for nanocatalysts Relates nanocatalysts' properties to their specific applications Proposes optimization methods aiming at specific applications

Download or read book Colloidal Metal Oxide Nanoparticles written by and published by Elsevier. This book was released on 2019-10-16 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt: Colloidal Metal Oxide Nanoparticles: Synthesis, Characterization and Applications is a one-stop reference for anyone with an interest in the fundamentals, synthesis and applications of this interesting materials system. The book presents a simple, effective and detailed discussion on colloidal metal oxide nanoparticles. It begins with a general introduction of colloidal metal oxide nanoparticles, then delves into the most relevant synthesis pathways, stabilization procedures, and synthesis and characterization techniques. Final sections discuss promising applications, including bioimaging, biosensing, diagnostic, and energy applications—i.e., solar cells, supercapacitors and environment applications—i.e., the treatment of contaminated soil, water purification and waste remediation. Provides the most comprehensive resource on the topic, from fundamentals, to synthesis and characterization techniques Presents key applications, including biomedical, energy, electronic and environmental Discusses the most relevant techniques for synthesis, patterning and characterization