Download or read book Structural Properties and Catalytic Activity of Some Mixed Metal Oxide written by Naira Samer Elmasry Metwally and published by . This book was released on 2017-04-02 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heterogeneous Catalysis of Mixed Oxides written by Makoto Misono and published by Elsevier Inc. Chapters. This book was released on 2013-02-28 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: The chemistry of metal oxides, both single and mixed metal oxides, relevant to heterogeneous catalysis such as relationships among the composition, structure, and chemical properties of mixed oxides, is provided in perspective. The important chemical properties in heterogeneous catalysis are acid–base and reduction–oxidation (redox) properties, where ionic radii, electronegativity, valency, and tendency to form covalent bond of constituent elements are most influential. Structural factors such as lattice defects and nonstoichiometry are also relevant. Although the surface of metal oxides is different from the solid bulk and changes depending on various factors, the surface reflects more or less the solid bulk and the knowledge of bulk properties is useful to understand the catalysis of mixed oxides. In some cases, the solid bulk actually takes part in catalysis. Other fundamental features of metal oxide catalysis like synergistic effects of more than two different active sites (acid and base, acid and oxidation, etc.) are also discussed.
Download or read book Nanocasting written by An-Hui Lu and published by Royal Society of Chemistry. This book was released on 2010 with total page 279 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanostructured materials with tailored properties are regarded as a fundamental element in the development of future science and technology. Research is still ongoing into the nanosized construction elements required to create functional solids. The recently developed technique, nanocasting, has great advantage over others in terms of the synthesis of special nanostructured materials by the careful choice of suitable elements and nanoengineering steps. This new book summarizes the recent developments in nanocasting, including the principles of nanocasting, syntheses of novel nanostructured materials, characterization methods, detailed synthetic recipes and further possible development in this area. The book focuses on the synthesis of porous solids from the viewpoint of methodology and introduces the science of nanocasting from fundamental principles to their use in synthesis of various materials. It starts by outlining the principles of nanocasting, requirements to the templates and precursors and the tools needed to probe matter at the nanoscale level. It describes how to synthesize nano structured porous solids with defined characteristics and finally discusses the functionalization and application of porous solids. Special attention is given to new developments in this field and future perspectives. A useful appendix covering the detailed synthetic recipes of various templates including porous silica, porous carbon and colloidal spheres is included which will be invaluable to researchers wanting to follow and reproduce nanocast materials. Topics covered in the book include: * inorganic chemistry * organic chemistry * solution chemistry * sol-gel and interface science * acid-base equilibria * electrochemistry * biochemistry * confined synthesis The book gives readers not only an overview of nanocasting technology, but also sufficient information and knowledge for those wanting to prepare various nanostructured materials without needing to search the available literature.
Download or read book Metal Oxide Catalysis 2 Volume Set written by S. David Jackson and published by John Wiley & Sons. This book was released on 2008-11-24 with total page 916 pages. Available in PDF, EPUB and Kindle. Book excerpt: With its two-volume structure, this handbook and ready reference allows for comprehensive coverage of both characterization and applications, while uniform editing throughout ensures that the structure remains consistent. The result is an up-to-date review of metal oxides in catalysis. The first volume covers a range of techniques that are used to characterize oxides, with each chapter written by an expert in the field. Volume 2 goes on to cover the use of metal oxides in catalytic reactions. For all chemists and engineers working in the field of heterogeneous catalysis.
Download or read book Metal Oxides in Heterogeneous Catalysis written by Jacques C. Vedrine and published by Elsevier. This book was released on 2018-01-11 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal Oxides in Heterogeneous Catalysis is an overview of the past, present and future of heterogeneous catalysis using metal oxides catalysts. The book presents the historical, theoretical, and practical aspects of metal oxide-based heterogeneous catalysis. Metal Oxides in Heterogeneous Catalysis deals with fundamental information on heterogeneous catalysis, including reaction mechanisms and kinetics approaches.There is also a focus on the classification of metal oxides used as catalysts, preparation methods and touches on zeolites, mesoporous materials and Metal-organic frameworks (MOFs) in catalysis. It will touch on acid or base-type reactions, selective (partial) and total oxidation reactions, and enzymatic type reactions The book also touches heavily on the biomass applications of metal oxide catalysts and environmentally related/depollution reactions such as COVs elimination, DeNOx, and DeSOx. Finally, the book also deals with future trends and prospects in metal oxide-based heterogeneous catalysis. Presents case studies in each chapter that provide a focus on the industrial applications Includes fundamentals, key theories and practical applications of metal oxide-based heterogeneous catalysis in one comprehensive resource Edited, and contributed, by leading experts who provide perspectives on synthesis, characterization and applications
Download or read book Transition Metal Oxides written by H.H. Kung and published by Elsevier. This book was released on 1989-04-01 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book the author presents an up-to-date summary of existing information on the structure, electronic properties, chemistry and catalytic properties of transition metal oxides. The subjects covered in the book can be divided into three sections. The first (chapters 1 to 3) covers the structural, physical, magnetic, and electronic properties of transition metal oxides. Although the emphasis is on surface properties, relevant bulk properties are also discussed. The second section (chapters 4 to 7) covers surface chemical properties. It includes topics that describe the importance of surface coordinative unsaturation in adsorption, the formation of surface acidity and the role of acidity in determining surface chemical properties, the nature and reactivities of adsorbed oxygen, and the surface chemistry in the reduction of oxides. The third section (chapters 8 to 14) is on the catalytic properties. Various catalytic reactions including decomposition, hydrogenation, isomerization, metathesis, selective oxidation, and reactions involving carbon oxides are discussed. Emphasis is placed more on reaction mechanisms and the role of catalysts than on kinetics and processes. Chapters on the preparation of oxide catalysts and on photo-assisted processes are also included. Whenever appropriate, relationships between various topics are indicated. Written for surface physicists, chemists, and catalytic engineers, the book will serve as a useful source of information for investigators and as a comprehensive overview of the subject for graduate students.
Download or read book Key Structural Factors of Group 5 Metal Oxide Clusters for Base Catalytic Application written by Shun Hayashi and published by Springer Nature. This book was released on 2020-08-08 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides detailed information on the base catalysis of group 5 (Nb, Ta) metal oxide clusters by elucidating how the structural factors such as constituent metals, counter cations, and local structures of base sites affect their catalysis. Uniquely, it reveals the effects of key structural factors at the molecular level by combining experimental and theoretical approaches. The findings presented here provide rational design principles for base catalysis and will foster the development of promising catalysts for solving current and future energy and environmental problems.
Download or read book Molecular Structure reactivity Relationships for Propane Oxidation Over Model Mixed Oxide Catalysts written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Mixed Mo-V-Sb-Nb and Mo-V-Te-Nb oxides were recently discovered as highly active and selective catalysts for the propane oxidation to propylene and oxygenates, i.e. acrolein and acrylic acid. Fundamental information is needed for understanding the bulk and surface molecular structure-activity/selectivity relationships and providing rules of rational design of improved mixed metal oxide catalysts for the selective oxidation of propane. The phase composition and catalytic activity of the model Mo-V-Sb-Nb-O system strongly depended on the synthesis route and composition. A number of distinct solid-state phases were observed in this system: Mo6V9O40, MoO3, rutile SbVO4 and the defect "Mo-V-Nb-O" phases. The kinetic studies indicated that the high selectivity to acrylic acid (2̃0 mol.%) was associated with the Mo6V9O40 and the defect "Mo-V-Nb-O" phases. The synthesis of these mixed Mo-V-Sb-Nb-O system was performed using combinatorial chemistry techniques to explore the utility of liquid phase automated synthesis for the reproducible preparation of these catalysts. This study indicated good reproducibility of phase compositions and catalytic properties and provided new insights into the transformation processes that occur in these oxides with time on stream. It was discovered in this research that the model mixed Mo-V-Te-O catalyst represents a simple model system for elucidating the molecular structure-activity/selectivity relationships in propane selective oxidation. This catalyst contains the two major crystalline phases proposed as active and selective for propane oxidation. This research elucidated the effect of the chemical composition, solution pH and thermal treatment on phase composition and catalytic performance. High resolution TEM study established the crystal structures of the hexagonal and orthorhombic phases in terms of their space groups, unit cell parameters, atomic coordinates and elemental compositions. In order to understand the role of the structure, morphology and composition of mixed Mo-V-Te-Nb-O system, novel synthesis approaches employing ordered arrays of colloidal polystyrene spheres (0.4 ưm) were successfully developed. These novel nanocrystalline catalysts with surface areas in the 80-110 m2/g range consisted of 20-50 nm particles of desirable catalytic phases and contained 6-20 nm pores. Kinetic studies demonstrated the acrylic acid yields exceeding 40 mol.% and approaching the commercial targets for the selective oxidation of propane to acrylic acid.
Download or read book the structural properties and catalytic activity of some mixed oxide catalysts written by mohammady ayman mohammed and published by . This book was released on 2004 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Metal Oxides written by J.L.G. Fierro and published by CRC Press. This book was released on 2005-08-24 with total page 808 pages. Available in PDF, EPUB and Kindle. Book excerpt: The chemistry of metals has traditionally been more understood than that of its oxides. As catalytic applications continue to grow in a variety of disciplines, Metal Oxides: Chemistry and Applications offers a timely account of transition-metal oxides (TMO), one of the most important classes of metal oxides, in the context of catalysis. The
Download or read book Adsorption and Catalysis on Transition Metals and Their Oxides written by Vsevolod F. Kiselev and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book deals with adsorption and catalysis on the surface of transition elements and their compounds, many of which are in teresting because of their particular electronic structure. The authors have worked through a vast body of experimental evi dence on the structure and properties of surfaces of transition metals and relevant oxides. Consideration is given mostly to simple (as opposed to mixed) oxides of transition elements, to common metals and to the adsorption of simple gases. A great deal of attention is paid to the nature of active surface sites responsible for chemisorption and catalytic transformations. The description relies mainly on the simplified ligand-field theory, which, however, proves quite satisfactory for predicting the adsorptive and catalytic activity of species. In many cases simple systems were explored with the aid of novel techniques, and it is only for such systems that the mechanism of the ele mentary act of adsorption and catalysis can be given adequate treatment. The present monograph has emerged from our earlier work in Russian, which appeared in the Khimiya Publishing House (Mos cow) in 1981. This English edition has, however, been revised completely to broaden its scope and to include more recent a chievements. For fruitful discussions the authors are grateful to A.A.
Download or read book Metal Oxide Based Heterostructures written by Naveen Kumar and published by Elsevier. This book was released on 2022-11-13 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal Oxide–Based Heterostructures: Fabrication and Applications provides information on synthesis strategies, structural and hierarchical features, morphological characteristics of metal oxide–based heterostructures, and their diverse applications. This book begins with an introduction to the various multidimensional heterostructures, synthesis aspects, and techniques used to control the formation of heterostructures. Then, the impact of synthesis routes on the formation of mixed metal oxide heterostructures and their properties are analyzed. The effect of nonmetal doping, metal doping, and composites of metal oxide heterostructures on the properties of heterostructures is also addressed and that also includes opportunities for optimization of the material’s performance for specific applications. Special attention is given to the surface characteristics of the metal oxide heterostructures and their impact on the material’s performance, and the applications of metal oxide heterostructures in various fields such as environmental remediation, sensing, organic catalysis, photovoltaics, light emitting materials, and hydrogen production. Introduces key principles for metal oxide heterostructures, their properties, key characteristics, and synthesis routes Emphasizes the relationship between synthesis strategies and material performance, including optimization strategies such as tailoring the material’s surface characteristics or structure Discusses metal oxide heterostructures and their application in lighting and displays, energy, environment, and sensing
Download or read book Advances in Metal Oxides and Their Composites for Emerging Applications written by Sagar D. Delekar and published by Elsevier. This book was released on 2022-08-26 with total page 745 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Metal Oxides and their Composites for Emerging Applications reviews key properties of metal-oxide based composites, including their structural, physicochemical, optical, electrical components and resulting performance in a wide range of diverse applications. Synthetic protocols used to create metal oxides with desirable morphologies, properties and performance for applications in solar energy harvesting, energy storage and environmental remediation are emphasized. Emerging technologies that address important global challenges such as energy shortage, the hazardous effects of non-renewable energy sources, unaffordable energy technologies, and the contaminants present in air and water are also covered. This book is an ideal resource for materials scientists and engineers working in academia and R&D. In addition, it's appropriate for those who either need an introduction to potential research directions or for experienced researchers and practitioners looking for a key reference on the latest advances. Introduces the fundamental properties of metal oxide-based composites, paying special attention to physicochemical, optical, electrical and structural characteristics Provides an overview of the synthetic protocols used to design and tune the properties of metal oxide-based composites for key emerging applications Discusses metal oxide-based composites and their use in energy applications such as energy storage, energy harvesting and environmental remediation
Download or read book Metal Oxides and Related Solids for Electrocatalytic Water Splitting written by Junlei Qi and published by Elsevier. This book was released on 2022-05-16 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal Oxides and Related Solids for Electrocatalytic Water Splitting reviews the fundamentals and strategies needed to design and fabricate metal oxide-based electrocatalysts. After an introduction to the key properties of transition metal oxides, materials engineering methods to optimize the performance of metal-oxide based electrocatalysts are discussed. Strategies reviewed include defect engineering, interface engineering and doping engineering. Other sections cover important categories of metal-oxide (and related solids) based catalysts, including layered hydroxides, metal chalcogenides, metal phosphides, metal nitrides, metal borides, and more. Each chapter introduces important properties and material design strategies, including composite and morphology design. There is also an emphasis on cost-effective materials design and fabrication for optimized performance for electrocatalytic water splitting applications. Lastly, the book touches on recently developed in-situ characterization methods applied to observe and control the material synthesis process. Introduces metal oxide-based materials for electrocatalytic water splitting applications, including their key properties, synthesis, design and fabrication strategies Reviews the most relevant materials design strategies, including defect engineering, interface engineering, and doping engineering Discusses the pros and cons of metal oxide-based materials for water splitting applications to aid in materials selection
Download or read book Correlations Between Surface Structure and Catalytic Activity written by and published by . This book was released on 1992 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Objective is to address the keys to understanding the relation between surface structure and catalytic activity/selectivity. Of concern are questions related to enhanced catalytic properties of mixed-metal catalysts and critical active site requirements for molecular synthesis and rearrangement. The experimental approach utilizes a microcatalytic reactor contiguous to a surface analysis system, an arrangement which allows in vacuo transfer of the catalyst from one chamber to the other. Surface techniques being used include Auger (AES), UV and X-ray photoemission spectroscopy (UPS and XPS), temperature programmed desorption (TPD), low energy electron diffraction (LEED), high resolution electron energy loss spectroscopy (HREELS) and infrared reflection-absorption spectroscopy (IRAS). Our research program builds upon our previous experience relating the results of single crystal kinetic measurements with the results obtained with supported analogs. As well we are exploiting our recent work on the preparation, the characterization, and the determination of the catalytic properties of ultra-thin metal and metal oxide films. The program is proceeding toward the study of the unique catalytic properties of ultrathin metal films; the investigation of the critical ensemble size requirements for principal catalytic reaction types; and the modelling of supported catalysts using ultra-thin planar oxide surfaces.
Download or read book One dimensional 1 D Nanostructured Metal Oxides for Catalytic Oxidation of Hydrocarbons written by Yunzhe Feng and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Catalytic oxidation of hydrocarbons has been intensively studied, with the purpose of minimizing emissions of pollutants and facilitating the combustion process. Noble metals, such as platinum and palladium, are the most effective catalysts for the oxidation of hydrocarbons. However, the limited supply of these noble metals imposes a need for developing alternative catalysts. Transition metal oxides are attractive alternatives due to their high thermal stability and low cost. Previous studies of metal oxide catalysts have focused on metal oxide nanoparticles (NPs) supported on porous substrates, such as Al2O3, ZrO2 and spinel-type (AB2O4) supports. Although the dispersed metal species over large surface area have shown much higher activity than the bulk metal oxide, there are several limitations. First, interactions between the support and NPs at high temperatures impede the fundamental understanding of the catalytic properties of individual NPs, and limit their application conditions. Moreover, the solid supports limit the loading of NPs because NPs tend to aggregate at large loadings, leading to a decrease in catalytic activity. Herein, one-dimensional (1-D) nanostructured metal oxide were directly grown on metal mesh substrates and used as catalysts for hydrocarbons oxidation. The 1-D nanostructured catalysts benefits from reduced interaction with the substrates, great flexibility in increasing the catalyst loading, and convenience in tuning the surface chemistry for higher catalytic activity, thus exhibit comparable or better catalytic activity and stability compared to the supported NPs. As one of the most active metal oxide catalysts, CuO was used as a model system to demonstrate the effectiveness of the 1-D nanostructured metal oxide catalysts. CuO NWs have been grown on Cu mesh by solid phase diffusion and applied to catalyze methane oxidation reactions. The CuO NWs have shown comparable or even better activity and stability than the supported CuO NPs. Moreover, owing to the fact that the NWs were exposed on the substrate surface and easy to access, two methods were used to tune the NWs for enhanced catalytic activity. The first one was to reduce the CuO NWs to more active Cu2O NWs by H2 plasma, which has shown 20% increase activity for CH4 oxidation reactions and several times higher activity for CO oxidation reactions. The kinetics study have shown that the bulk oxygen diffusion in Cu2O was faster, which could be one of the reasons for higher activity of Cu2O than that of CuO. The second tuning method was to decorate the CuO NWs with more active NP materials, such as Co3O4 and noble metals with a newly developed simple, fast and general sol-flame method. After the Co3O4 decoration, the CuO NWs surface was uniformly and densely covered by Co3O4 NP-chain structures, with large NP loading, high surface area and minimal aggregation, resulting in times higher activity in catalyzing CH4 oxidation. Moreover, this sol-flame method is a general method to decorate NWs with various NPs, and even to dope NWs with dopants for desirable properties. Given the generality and simplicity of the sol-flame methods, it can be applied to not only catalysis, but also other important application areas, such as lithium ion battery, supercapacitor and photoelectrochemical devices. In addition, to incorporate Cu and Co, the most active metal oxide catalyst Co3O4 was grown as 1-D structure on stainless steel mesh with the Cu2+ ion enhanced ammonia-evaporation-induced synthesis method. The synergetic effects of Cu and Co in catalytic process were studied, which have shown that the Cu2+ improved the nucleation and growth process of 1-D Co3O4, however, the catalytic activity is mainly from the Co species.
Download or read book Chemistry of Nanocrystalline Oxide Materials written by K. C. Patil and published by World Scientific. This book was released on 2008 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nano-oxide materials lend themselves to applications in a wide variety of emerging technological fields such as microelectronics, catalysts, ceramics, coatings, and energy storage. However, developing new routes for making nano-based materials is a challenging area for solid-state materials chemists. This book does just that by describing a novel method for preparing them. The authors have developed a novel low-temperature, self-propagating synthetic route to nano-oxides by the solution combustion and combustible precursor processes. This method provides the desired composition, structure, and properties for many types of technologically useful nanocrystalline oxide materials like alumina, ceria, iron oxides, titania, yttria, and zirconia, among others.The book is particularly instructive in bringing readers one step closer to the exploration of nanomaterials. Students of nanoscience can acquaint themselves with the actual production and evaluation of nanopowders by this route, while academic researchers and industrial scientists will find answers to a host of questions on nano-oxides. The book also provides an impetus for scientists in industrial research to evaluate and explore new ways to scale up the production of nanomaterials, offering helpful suggestions for further research.
