Download or read book In Situ Spectroscopy of Metal Oxides Reveal Electrocatalyst Structure property Relationships written by Chuhyon John Eom and published by . This book was released on 2020 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: The structure-property relationship is a foundational concept of materials science and engineering. Tuning the catalytic properties of materials by varying their structural properties like stoichiometry and crystal facets have been integral to advances in electrocatalysis. Traditionally, these studies rely on ex situ, bulk structural characterizations to describe catalytic properties. Catalysis, however, occurs on a dynamic catalytic surface sensitive to its local environment. This dissertation uses in situ spectroscopy of metal oxide electrocatalysts to better capture the intricacies of such catalyst structure-property relationships. La2/3S1/3rMnO3 films are grown using molecular beam epitaxy for a controlled study on the effects of surface and sub-surface structure of metal oxides on the oxygen reduction reaction (ORR) catalysis. Ambient pressure X-ray photoelectron spectroscopy of the films show that the surface and sub-surface structures control the balance between electronic benefits vs. parasitic surface reactions for the ORR. The low atomic number group of an amorphous cobalt oxide catalyst in a phosphate network (CoPi) is studied using home-built stimulated Raman spectroscopy (SRS). In situ SRS reveals previously unreported phosphate motifs in CoPi under oxygen evolution reaction conditions. Isotopic studies show that the phosphate structure is intimately linked to the aqueous environment with implications for the catalyst microstructure and deposition. Extensions of the dissertation on the in situ spectroscopy of a quinone electrochemical systems is discussed in the end.

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 Structure Processing Properties Relationships in Stoichiometric and Nonstoichiometric Oxides written by Speranta Tanasescu and published by BoD – Books on Demand. This book was released on 2020-11-04 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: The interrelation among composition, microstructure, and properties of stoichiometric and nonstoichiometric compounds is a major field of research for both scientific and technological reasons. As such, this book focuses on metal oxides, which present a large diversity of electrical, magnetic, optical, optoelectronic, thermal, electrochemical, and catalytic properties, making them suitable for a wide range of applications. By bringing together scientific contributions with special emphasis on the interrelations between materials chemistry, processing, microstructures, and properties of stoichiometric and nonstoichiometric metal oxides, this book highlights the importance of tightly integrating high-throughput experiments (including both synthesis and characterization) and efficient and robust theory for the design of advanced materials.

Download or read book Noble metal free Electrocatalysts For Hydrogen Energy written by Qingsheng Gao and published by World Scientific. This book was released on 2022-08-23 with total page 606 pages. Available in PDF, EPUB and Kindle. Book excerpt: With interdisciplinary perspectives from internationally renowned experts, Noble-Metal-Free Electrocatalysts for Hydrogen Energy is one of the most authoritative references to focus solely on state-of-the-art knowledge of noble-metal-free electrocatalysts, as well as their nanostructures and unique properties. The chapters within contain cutting-edge breakthroughs, horizons, and insights into functional materials for energy applications.This book contains over 3000 references and 200 figures, and is a highly valuable resource for scientists, students, and engineers working in the fields of electrochemistry, catalysis, fuel cells, batteries, and supercapacitors.

Download or read book Metal Oxides as Electrocatalysts at Oxygen Electrodes in Electrochemical Systems written by Shuai Zhao and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fuel cells, one of the most widely studied electrochemical energy conversion devices, together with electrolyzers, a promising energy storage system for natural renewable energy and source of purified hydrogen, have attracted significant research attention in recent years as the demand for energy continues to increase with no end to this energy expansion in sight. However, electrochemical reactions occurring at oxygen electrodes such as the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) have very slow kinetics, which has limited the industrialization of both fuel cells and electrolyzers because slow kinetics leads directly high reaction overpotentials. Metal oxides have been widely adopted in terms of electrocatalysts for these oxygen reactions, either as as a support to enhance the stability or activity of platinum, or as the direct catalysts for ORR and OER in alkaline media. However, what is not known is how and why metal oxides as support materials can influence the performance of precious metals through their interactions, what the active sites are for different electrochemical reactions and how to control the desired phases by manipulating the synthesis conditions. This study will probe these very important questions. Chapter 1 of this work provides a background into the ORR/OER mechanism, active sites, and catalyst candidates in electrochemical devices. Chapter 2 presents experimental approaches including material synthesis, and both physical and electrochemical characterization. Chapters 3 and 4 of this study investigate doped metal carbides and metal oxides as support materials for platinum and iridium catalysts for the ORR and OER, respectively, in acidic electrolytes. The Chapter 3 is an investigation of tungsten carbide modified with titanium as a potential non-carbon support for platinum during the ORR in acid media. Chapter 4 discusses the relationship between the synthesis parameters of iridium/iridium oxide supported on titanium-doped tungsten oxide and its durability both ex-situ in a three-electrode cell on a rotating disk electrode (RDE) and in-situ in an operating electrolyzer. Chapter 5 discusses a new method to determine the electrochemically active area of iridium oxide, one of the most common anode catalysts in commercial PEM electrolyzers, in-situ through its electrochemical psuedocapacitance. Chapter 6 probes the performance and function of tin-doped indium oxides (ITO) as a support for platinum ORR catalyst in alkaline media. Metal-support interactions were studied mainly through X-ray photoelectron spectroscopy and electrochemical measurements. Chapter 7 focuses on the electrocatalysis of carbon nanotube (CNT)-supported cobalt oxide for both oxygen reduction and evolution reactions in alkaline media. An optimized procedure to produce a highly stable and active bifunctional ORR/OER hybrid catalyst was developed along with an understanding of the impact of metal oxide anchoring sites and synthesis parameters on catalyst durability. This part of the study provides novel perspectives for the design of carbon-based, hybrid materials and insight into the synthesis-property relationships for these and future electrocatalysts. In summary, this work has studied metal oxides as catalysts and support materials for precious metals during aqueous oxygen reactions. Wherever possible, the fundamental cause for their behavior, including enhanced electrocatalytic activity and durability, was probed thoroughly through physical and electrochemical characterization.

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 first part of the book examines the crystal and electronic structure, stoichiometry and composition, redox properties, acid-base character, and cation valence states, as well as new approaches to the preparation of ordered TMO with extended structure of texturally defined systems. The second part compiles some practical aspects of TMO applications in materials science, chemical sensing, analytical chemistry, solid-state chemistry, microelectronics, nanotechnology, environmental decontamination, and fuel cells. The book examines many types of reactions - such as dehydration, reduction, selective oxidations, olefin metathesis, VOC removal, photo- and electrocatalysis, and water splitting - to elucidate how chemical composition and optical, magnetic, and structural properties of oxides affect their surface reactivity in catalysis. Drawing insight from leading international experts, Metal Oxides: Chemistry and Applications is a comprehensive and interdisciplinary reference for researchers that may also be used by newcomers as a guide to the field.

Download or read book Structure property Relationships in Complex Oxides written by Iflah Laraib and published by . This book was released on 2022 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: Finally, we analyze the performance of different functionals in describing the electronic structure of several metal oxides, focusing on band gap, ionization potential (IP), and electron affinity (EA). We employ methods that go beyond the semi(local) approximations in density functional theory to inspect how ionization potentials and electron affinities are corrected, discussing in particular the performance of the meta-GGA SCAN, DFT+U, and hybrid functionals in the description of some representative semiconductors, band insulators, and Mott insulators, by comparing with available experimental data. We find that with a careful choice of U, DFT+U does correct band gaps in most cases, however, it often leads to wrong descriptions of IP and EA; whereas the screened hybrid functional of Heyd-Scuseria-Ernzerhof with appropriate mixing parameter, leads to accurate description of IP and EA in most cases. Our work indicates that interpretations of widely used high-throughput screening of materials for catalysis, photovoltaics, or batteries (where IP and EA, and band gaps are crucial parameters) based on the computationally inexpensive DFT+U method should be taken with great care.

Download or read book Amorphous Nanomaterials written by Lin Guo and published by John Wiley & Sons. This book was released on 2021-06-01 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: A valuable overview covering important fundamental and applicative aspects of amorphous nanomaterials! Amorphous nanomaterials are very important in non-crystalline solids, which have emerged as a new category of advanced materials. Compared to the crystalline counterpart, amorphous nanomaterials with isotropic nature always exhibit fast ion diffusion, relieved strain, and higher reactivity, enabling such materials to exhibit high performance in mechanics and catalysis, as well as other interesting properties. Amorphous Nanomaterials: Preparation, Characterization, and Applications covers the fundamental concept, synthesis, characterization, properties, and applications of nanoscaled amorphous materials. It starts with the introduction of amorphous materials, then gives a global view of the history, structure, and growth mechanism of amorphous nanomaterials. Subsequently, some powerful techniques to characterize amorphous materials, such as X-ray absorption fine structure spectroscopy, spherical aberration electron microscope, in-situ-Transmission Electron Microscope, Electron Energy Loss Spectroscopy, and some other defect characterization technologies are included. Furthermore, the emerging innovative methods to fabricate well-defined, regularshaped amorphous nanomaterials, including zero-, one-, two-, and three-dimensional amorphous nanomaterials are systematically introduced. The fascinating properties and applications related to amorphous nanomaterials including the applications in electrocatalysis, batteries, supercapacitors, photocatalysis, mechanics, etc., are presented. It will greatly help the researchers to find professional answers related to amorphous materials. Great topic: amorphous nanomaterials are a very large and important field in both academia and industry Comprehensive: in-depth discussion of various important aspects, from both a fundamental and an applied point of view, on the chemistry, physics and technological importance of the amorphous nanomaterials are presented Vitally needed: the understanding of the fundamentals of amorphous nanomaterials is a prerequisite for devising new applications of such materials Highly relevant: amorphous nanomaterials have found specific applications in chemistry, catalysis, physics, sensing, batteries, supercapacitors, and engineering Amorphous Nanomaterials is a vital resource for materials scientists, inorganic and physical chemists, solid state chemists, physicists, catalytic and analytical chemists, as well as organic chemists.

Download or read book Introduction to XAFS written by Grant Bunker and published by Cambridge University Press. This book was released on 2010-01-28 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: X-ray absorption fine structure spectroscopy (XAFS) is a powerful and versatile technique for studying structures of materials in chemistry, physics, biology and other fields. This textbook is a comprehensive, practical guide to carrying out and interpreting XAFS experiments. Assuming only undergraduate-level physics and mathematics, the textbook is ideally suited for graduate students in physics and chemistry starting XAFS-based research. It contains concise executable example programs in Mathematica 7. Supplementary material available at www.cambridge.org/9780521767750 includes Mathematica code from the book, related Mathematica programs, and worked data analysis examples. The textbook addresses experiment, theory, and data analysis, but is not tied to specific data analysis programs or philosophies. This makes it accessible to a broad audience in the sciences, and a useful guide for researchers entering the subject.

Download or read book Perovskite Oxide for Solid Oxide Fuel Cells written by Tatsumi Ishihara and published by Springer Science & Business Media. This book was released on 2009-06-12 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fuel cell technology is quite promising for conversion of chemical energy of hydrocarbon fuels into electricity without forming air pollutants. There are several types of fuel cells: polymer electrolyte fuel cell (PEFC), phosphoric acid fuel cell (PAFC), molten carbonate fuel cell (MCFC), solid oxide fuel cell (SOFC), and alkaline fuel cell (AFC). Among these, SOFCs are the most efficient and have various advantages such as flexibility in fuel, high reliability, simple balance of plant (BOP), and a long history. Therefore, SOFC technology is attracting much attention as a power plant and is now close to marketing as a combined heat and power generation system. From the beginning of SOFC development, many perovskite oxides have been used for SOFC components; for example, LaMnO -based oxide for the cathode and 3 LaCrO for the interconnect are the most well known materials for SOFCs. The 3 current SOFCs operate at temperatures higher than 1073 K. However, lowering the operating temperature of SOFCs is an important goal for further SOFC development. Reliability, durability, and stability of the SOFCs could be greatly improved by decreasing their operating temperature. In addition, a lower operating temperature is also beneficial for shortening the startup time and decreasing energy loss from heat radiation. For this purpose, faster oxide ion conductors are required to replace the conventional Y O -stabilized ZrO 2 3 2 electrolyte. A new class of electrolytes such as LaGaO is considered to be 3 highly useful for intermediate-temperature SOFCs.

Download or read book Ionisation Constants of Inorganic Acids and Bases in Aqueous Solution written by D. D. Perrin and published by Elsevier. This book was released on 2016-09-14 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ionisation Constants of Inorganic Acids and Bases in Aqueous Solution, Second Edition provides a compilation of tables that summarize relevant data recorded in the literature up to the end of 1980 for the ionization constants of inorganic acids and bases in aqueous solution. This book includes references to acidity functions for strong acids and bases, as well as details about the formation of polynuclear species. This text then explains the details of each column of the tables, wherein column 1 gives the name of the substance and the negative logarithm of the ionization constant and column 2 gives the temperature of measurements in degree Celsius. This book presents as well the method of measurement and the literature references that are listed alphabetically at the end of the tables. Chemists will find this book useful.

Download or read book Fabrication of Metal Organic Framework Derived Nanomaterials and Their Electrochemical Applications written by Wei Xia and published by Springer. This book was released on 2018-04-03 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis systematically introduces readers to a new metal-organic framework approach to fabricating nanostructured materials for electrochemical applications. Based on the metal-organic framework (MOF) approach, it also demonstrates the latest ideas on how to create optimal MOF and MOF-derived nanomaterials for electrochemical reactions under controlled conditions. The thesis offers a valuable resource for researchers who want to understand electrochemical reactions at nanoscale and optimize materials from rational design to achieve enhanced electrochemical performance. It also serves as a useful reference guide to fundamental research on advanced electrochemical energy storage materials and the synthesis of nanostructured materials.

Download or read book Liquid Cell Electron Microscopy written by Frances M. Ross and published by Cambridge University Press. This book was released on 2017 with total page 529 pages. Available in PDF, EPUB and Kindle. Book excerpt: 2.6.2 Electrodes for Electrochemistry

Download or read book X Ray Absorption Spectroscopy of Semiconductors written by Claudia S. Schnohr and published by Springer. This book was released on 2014-11-05 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: X-ray Absorption Spectroscopy (XAS) is a powerful technique with which to probe the properties of matter, equally applicable to the solid, liquid and gas phases. Semiconductors are arguably our most technologically-relevant group of materials given they form the basis of the electronic and photonic devices that now so widely permeate almost every aspect of our society. The most effective utilisation of these materials today and tomorrow necessitates a detailed knowledge of their structural and vibrational properties. Through a series of comprehensive reviews, this book demonstrates the versatility of XAS for semiconductor materials analysis and presents important research activities in this ever growing field. A short introduction of the technique, aimed primarily at XAS newcomers, is followed by twenty independent chapters dedicated to distinct groups of materials. Topics span dopants in crystalline semiconductors and disorder in amorphous semiconductors to alloys and nanometric material as well as in-situ measurements of the effects of temperature and pressure. Summarizing research in their respective fields, the authors highlight important experimental findings and demonstrate the capabilities and applications of the XAS technique. This book provides a comprehensive review and valuable reference guide for both XAS newcomers and experts involved in semiconductor materials research.

Download or read book Oxide Surfaces written by and published by Elsevier. This book was released on 2001-05-21 with total page 677 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book is a multi-author survey (in 15 chapters) of the current state of knowledge and recent developments in our understanding of oxide surfaces. The author list includes most of the acknowledged world experts in this field. The material covered includes fundamental theory and experimental studies of the geometrical, vibrational and electronic structure of such surfaces, but with a special emphasis on the chemical properties and associated reactivity. The main focus is on metal oxides but coverage extends from 'simple' rocksalt materials such as MgO through to complex transition metal oxides with different valencies.

Download or read book Chemically Deposited Nanocrystalline Metal Oxide Thin Films written by Fabian I. Ezema and published by Springer Nature. This book was released on 2021-06-26 with total page 926 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book guides beginners in the areas of thin film preparation, characterization, and device making, while providing insight into these areas for experts. As chemically deposited metal oxides are currently gaining attention in development of devices such as solar cells, supercapacitors, batteries, sensors, etc., the book illustrates how the chemical deposition route is emerging as a relatively inexpensive, simple, and convenient solution for large area deposition. The advancement in the nanostructured materials for the development of devices is fully discussed.

Download or read book Handbook of Reference Electrodes written by György Inzelt and published by Springer Science & Business Media. This book was released on 2013-04-16 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reference Electrodes are a crucial part of any electrochemical system, yet an up-to-date and comprehensive handbook is long overdue. Here, an experienced team of electrochemists provides an in-depth source of information and data for the proper choice and construction of reference electrodes. This includes all kinds of applications such as aqueous and non-aqueous solutions, ionic liquids, glass melts, solid electrolyte systems, and membrane electrodes. Advanced technologies such as miniaturized, conducting-polymer-based, screen-printed or disposable reference electrodes are also covered. Essential know-how is clearly presented and illustrated with almost 200 figures.