Structure and Reactivity in Catalytic Systems Involving Metal Oxides and Electrode Surfaces

Structure and Reactivity in Catalytic Systems Involving Metal Oxides and Electrode Surfaces PDF Author: John M. White
Publisher:
ISBN:
Category :
Languages : en
Pages : 3

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Book Description
Secondary ion mass spectrometry as a kinetic tool was developed was used to characterize a number of interesting metal-metal oxides and metal-adsorbate systems. The most significant of these include the behavior of rhodium and platinum on titanium dioxide thin films. We showed conclusively that the rhodium and platinum on titanium dioxide thin films. We showed conclusively that the rhodium and platinum overlayers become encapsulated with TiO when these metals on metal oxides are heated. This is the most direct evidence of longstanding interest in strong metal support interactions for the mechanism by which the interaction occurs. We have also characterized carefully the role of small amounts of impurities in noble metals and their influence on catalysis . These levels are established by secondary ion mass spectroscopy and lie below the detectability limits of Auger electron spectroscopy. Finally, we have established the kinetics of surface decomposition of species like methoxide on platinum using SIMS to monitor the decomposition channels directly.

Structure and Reactivity in Catalytic Systems Involving Metal Oxides and Electrode Surfaces

Structure and Reactivity in Catalytic Systems Involving Metal Oxides and Electrode Surfaces PDF Author: John M. White
Publisher:
ISBN:
Category :
Languages : en
Pages : 3

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Book Description
Secondary ion mass spectrometry as a kinetic tool was developed was used to characterize a number of interesting metal-metal oxides and metal-adsorbate systems. The most significant of these include the behavior of rhodium and platinum on titanium dioxide thin films. We showed conclusively that the rhodium and platinum on titanium dioxide thin films. We showed conclusively that the rhodium and platinum overlayers become encapsulated with TiO when these metals on metal oxides are heated. This is the most direct evidence of longstanding interest in strong metal support interactions for the mechanism by which the interaction occurs. We have also characterized carefully the role of small amounts of impurities in noble metals and their influence on catalysis . These levels are established by secondary ion mass spectroscopy and lie below the detectability limits of Auger electron spectroscopy. Finally, we have established the kinetics of surface decomposition of species like methoxide on platinum using SIMS to monitor the decomposition channels directly.

Metal Oxide Catalysis, 2 Volume Set

Metal Oxide Catalysis, 2 Volume Set PDF Author: S. David Jackson
Publisher: John Wiley & Sons
ISBN: 9783527318155
Category : Science
Languages : en
Pages : 916

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Book Description
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.

Supported Metals in Catalysis

Supported Metals in Catalysis PDF Author: James Arthur Anderson
Publisher: World Scientific
ISBN: 184816677X
Category : Science
Languages : en
Pages : 581

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Book Description
With contributions from experts in supported metal catalysis, from both the industry and academia, this book presents the latest developments in characterization and application of supported metals in heterogeneous catalysis. In addition to a thorough and updated coverage of the traditional aspects of heterogeneous catalysis such as preparation, characterization and use in well-established technologies such as Naphtha reforming, the book also includes emerging areas where supported metal catalysis will make significant contributions in future developments, such as fuel cells and fine chemicals synthesis. The second edition of Supported Metals in Catalysis comes complete with new and updated chapters containing important summaries of research in a rapidly evolving field. Very few other books deal with this highly pertinent subject matter, and as such, it is a must-have for anyone working in the field of heterogeneous catalysis.

Technical Reports Awareness Circular : TRAC.

Technical Reports Awareness Circular : TRAC. PDF Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 620

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Book Description


Understanding the Catalytic Activity of Oxides Through Their Electronic Structure and Surface Chemistry

Understanding the Catalytic Activity of Oxides Through Their Electronic Structure and Surface Chemistry PDF Author: Kelsey Ann Stoerzinger
Publisher:
ISBN:
Category :
Languages : en
Pages : 181

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Book Description
The intermittent nature of renewable energy sources requires a clean, scalable means of converting and storing energy. Water electrolysis can sustainably achieve this goal by storing energy in the bonds of oxygen and hydrogen molecules. The efficiency of this storage-conversion process is largely determined by the kinetic overpotential required for the oxygen evolution and reduction reactions (OER and ORR), respectively. This thesis focuses on transition metal oxides as alternative oxygen catalysts to costly and scarce noble metals. In order to develop descriptors to improve catalytic activity, thus reducing material cost for commercial technologies, this work studies fundamental processes that occur on model catalyst systems. Electrochemical studies of epitaxial oxide thin films establish the intrinsic activity of oxide catalysts in a way that cannot be realized with polydisperse nanoparticle systems. This thesis has isolated the activity of the catalyst on a true surface-area basis, enabling an accurate comparison of catalyst chemistries, and also revealed how different terminations and structures affect the kinetics. These studies of epitaxial thin films are among the first to probe phenomena that are not straightforward to isolate in nanoparticles, such as the role of oxide band structure, interfacial charge transfer (the "ligand" effect), strain, and crystallographic orientation. In addition, these well-defined surfaces allow spectroscopic examinations of their chemical speciation in an aqueous environment by using ambient pressure X-ray photoelectron spectroscopy. By quantifying the formation of hydroxyl groups, we compare the relative affinity of different surfaces for this key reaction intermediate in oxygen electrocatalysis. The strength of interaction with hydroxyls correlates inversely with activity, illustrating detrimental effects of strong water interactions at the catalyst surface. This fundamental insight brings molecular understanding to the wetting of oxide surfaces, as well as the role of hydrogen bonding in catalysis. Furthermore, understanding of the mechanisms of oxygen electrocatalysis guides the rational design of high-surface-area oxide catalysts for technical application.

Metal Oxides in Heterogeneous Catalysis

Metal Oxides in Heterogeneous Catalysis PDF Author: Jacques C. Vedrine
Publisher: Elsevier
ISBN: 0128116323
Category : Technology & Engineering
Languages : en
Pages : 620

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Book Description
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

Surface Organometallic Chemistry: Molecular Approaches to Surface Catalysis

Surface Organometallic Chemistry: Molecular Approaches to Surface Catalysis PDF Author: Jean-Marie Basset
Publisher: Springer Science & Business Media
ISBN: 9400929714
Category : Science
Languages : en
Pages : 340

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Book Description
Surface organometallic chemistry is a new field bringing together researchers from organometallic, inorganic, and surface chemistry and catalysis. Topics ranging from reaction mechanisms to catalyst preparation are considered from a molecular basis, according to which the "active site" on a catalyst surface has a supra-molecular character. This. the first book on the subject, is the outcome of a NATO Workshop held in Le Rouret. France, in May. 1986. It is our hope that the following chapters and the concluding summary of recommendations for research may help to provide a definition of surface organometallic chemistry. Besides catalysis. the central theme of the Workshop, four main topics are considered: 1) Reactions of organometallics with surfaces of metal oxides, metals. and zeolites; 2) Molecular models of surfaces, metal oxides, and metals; 3) Molecular approaches to the mechanisms of surface reactions; 4) Synthesis and modification of zeolites and related microporous solids. Most surface organometallic chemistry has been carried out on amorphous high-surf ace-area metal oxides such as silica. alumina. magnesia, and titania. The first chapter. contributed by KNOZINGER. gives a short summary of the structure and reactivity of metal oxide surfaces. Most of our understanding of these surfaces is based on acid base and redox chemistry; this chemistry has developed from X-ray and spectroscopic data, and much has been inferred from the structures and reactivities of adsorbed organic probe molecules. There are major opportunities for extending this understanding by use of well-defined (single crystal) oxide surfaces and organometallic probe molecules.

Metal Nanoparticles for Catalysis

Metal Nanoparticles for Catalysis PDF Author: Franklin Tao
Publisher: Royal Society of Chemistry
ISBN: 1782621032
Category : Technology & Engineering
Languages : en
Pages : 285

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Book Description
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.

Springer Handbook of Surface Science

Springer Handbook of Surface Science PDF Author: Mario Rocca
Publisher: Springer Nature
ISBN: 3030469069
Category : Science
Languages : en
Pages : 1273

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Book Description
This handbook delivers an up-to-date, comprehensive and authoritative coverage of the broad field of surface science, encompassing a range of important materials such metals, semiconductors, insulators, ultrathin films and supported nanoobjects. Over 100 experts from all branches of experiment and theory review in 39 chapters all major aspects of solid-state surfaces, from basic principles to applications, including the latest, ground-breaking research results. Beginning with the fundamental background of kinetics and thermodynamics at surfaces, the handbook leads the reader through the basics of crystallographic structures and electronic properties, to the advanced topics at the forefront of current research. These include but are not limited to novel applications in nanoelectronics, nanomechanical devices, plasmonics, carbon films, catalysis, and biology. The handbook is an ideal reference guide and instructional aid for a wide range of physicists, chemists, materials scientists and engineers active throughout academic and industrial research.

Molecular Structure-reactivity Relationships for Propane Oxidation Over Model Mixed Oxide Catalysts

Molecular Structure-reactivity Relationships for Propane Oxidation Over Model Mixed Oxide Catalysts PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
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.