STOICHIOMETRY AND MATERIALS SCIENCE – WHEN NUMBERS MATTER Edited by Alessio Innocenti and Norlida Kamarulzaman Stoichiometry and Materials Science – When Numbers Matter Edited by Alessio Innocenti and Norlida Kamarulzaman Published by InTech Janeza Trdine 9, 51000 Rijeka, Croatia Copyright © 2012 InTech All chapters are Open Access distributed under the Creative Commons Attribution 3.0 license, which allows users to download, copy and build upon published articles even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. After this work has been published by InTech, authors have the right to republish it, in whole or part, in any publication of which they are the author, and to make other personal use of the work. Any republication, referencing or personal use of the work must explicitly identify the original source. As for readers, this license allows users to download, copy and build upon published chapters even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. Notice Statements and opinions expressed in the chapters are these of the individual contributors and not necessarily those of the editors or publisher. No responsibility is accepted for the accuracy of information contained in the published chapters. The publisher assumes no responsibility for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained in the book. Publishing Process Manager Silvia Vlase Technical Editor Teodora Smiljanic Cover Designer InTech Design Team First published April, 2012 Printed in Croatia A free online edition of this book is available at www.intechopen.com Additional hard copies can be obtained from orders@intechopen.com Stoichiometry and Materials Science – When Numbers Matter, Edited by Alessio Innocenti and Norlida Kamarulzaman p. cm. ISBN 978-953-51-0512-1 Contents Preface IX Part 1 Stoichiometry and Nanotechnology 1 Chapter 1 Clay Mineral Nanotubes: Stability, Structure and Properties 3 Hélio A. Duarte, Maicon P. Lourenço, Thomas Heine and Luciana Guimarães Chapter 2 Stoichiometric Boron-Based Nanostructures 25 Limin Cao, Xiangyi Zhang, Wenkui Wang and Min Feng Part 2 Defect Chemistry: Stoichiometry and Surface Structures 47 Chapter 3 Ellipsometry and Its Applications in Stoichiometry 49 Yu-Xiang Zheng, Rong-Jun Zhang and Liang-Yao Chen Chapter 4 Structure, Morphology, and Stoichiometry of GaN(0001) Surfaces Through Various Cleaning Procedures 83 Azusa N. Hattori and Katsuyoshi Endo Chapter 5 Nonstoichiometry and Properties of SnTe Semiconductor Phase of Variable Composition 105 Elena Rogacheva Part 3 The Influence of Stoichiometry on Intermetallic Compounds Features 145 Chapter 6 Stoichiometry in Inter-Metallic Compounds for Hydrogen Storage Applications 147 Kwo Young VI Contents Part 4 A Stoichiometric Approach to the Analysis of Metal Oxides Properties 173 Chapter 7 Determination of Thermodynamic and Transport Properties of Non-Stoichiometric Oxides 175 Mauvy Fabrice and Fouletier Jacques Chapter 8 Oxygen Potentials and Defect Chemistry in Nonstoichiometric (U,Pu)O 2 203 Masato Kato Chapter 9 Molar Volume, Ionic Radii in Stoichiometric and Nonstoichiometric Metal Oxides 219 Andrzej Stokłosa Part 5 The Importance of Stoichiometry in Electrochemcal Applications 245 Chapter 10 Synthesis and Stoichiometric Analysis of a Li-Ion Battery Cathode Material 247 Norlida Kamarulzaman and Mohd Hilmi Jaafar Chapter 11 A Study on Hydrogen Reaction Kinetics of Pt/HfO 2 /SiC Schottky-Diode Hydrogen Sensors 263 W.M. Tang, C.H. Leung and P.T. Lai Part 6 Stoichiometry Driven Solid Phase Synthesis 283 Chapter 12 Observation of Chemical Reactions in Solid Phase Using X-Ray Photoelectron Spectroscopy 285 Sergey P. Suprun, Valeriy G. Kesler and Evgeniy V. Fedosenko Chapter 13 The Solid-Phase Synthesis of the Inorganic Non-Stoichiometric Compounds-Fibrous Fluorosilicates 327 Naira B. Yeritsyan and Lida A. Khachatryan Part 7 The Role of Stoichiometry in Energy Production 355 Chapter 14 Chemical Transformations in Inhibited Flames over Range of Stoichiometry 357 O.P. Korobeinichev, A.G. Shmakov and V.M. Shvartsberg Chapter 15 Improved Combustion Control in Diesel Engines Through Active Oxygen Concentration Compensation 391 Jason Meyer and Stephen Yurkovich Contents VII Chapter 16 Stoichiometric Approach to the Analysis of Coal Gasification Process 415 Mamoru Kaiho and Osamu Yamada Preface Materials are so important in the development of civilization that we associate Ages with them. In the origin of human life on Earth, the Stone Age, people used only natural materials, like stone, clay, skins, and wood. When people found copper and how to make it harder by alloying, the Bronze Age started about 3000 BC. The use of iron and steel, a stronger material that gave advantage in wars started at about 1200 BC. The next big step was the discovery of a cheap process to make steel around 1850, which enabled the railroads and the building of the modern infrastructure of the industrial world. Materials are thus important to mankind because of the benefits that can be derived from the manipulation of their properties. Examples include electrical conductivity, dielectric constant, magnetization, optical transmittance, strength and toughness. The combination of physics, chemistry, and the focus on the relationship between the properties of a material and its microstructure is the domain of Materials Science. This is an interdisciplinary field, applying the properties of matter to various areas of science and engineering, which investigates the relationship between the structure of materials at atomic or molecular scales and their macroscopic properties. All the specific features of a material basically originate from the internal structures of the materials, including their types of atoms, the local configurations of the atoms, and the arrangements of these configurations into microstructures. Everything in the environment, whether naturally occurring or of human design, is composed of chemicals. Chemists and materials scientists search for new knowledge about chemicals and use it to improve life. Chemical research has led to the discovery and development of new and improved synthetic fibers, paints, adhesives, drugs, cosmetics, electronic components, lubricants, and thousands of other products. Chemists and materials scientists also develop processes that save energy and reduce pollution. Applications of materials science include studies of superconducting materials, graphite materials, integrated-circuit chips, and fuel cells. Research on the chemistry of living things spurs advances in medicine, agriculture, food processing, and other fields. X Preface In basic research, materials science investigates the properties, composition, and structure of matter and the laws that govern the combination of elements and reactions of substances to each other. In applied R&D, the scientists create new products and processes or improve existing ones, often using knowledge gained from basic research. In fact, virtually all chemists are involved in this quest in one way or another. The work of materials chemists is similar to, but separate from, the work of materials scientists. Materials scientists tend to have a more interdisciplinary background, as they apply the principles of physics and engineering as well as chemistry to study all aspects of materials. Chemistry, however, plays the primary role in materials science because it provides information about the structure and composition of materials. Hence, it is clearly evident how stoichiometry plays a crucial role in approaching the physical and chemical analysis of any material. Physical properties of materials usually play an important role in the selection of material for a particular application. This involves many factors such as material composition and structure, fracture and stress analysis, conductivity, optical, and thermal properties, to name a few. It also involves design, modeling, simulation, processing, and production methods. Research in the field of materials science involves many peripheral areas including crystallography, microscopy, lithography, mineralogy, photonics, and powder diffraction. That being so, the question “Why Study Materials Science?” might have several answers, referable to three main targets: To be able to select a material for a given use based on considerations of cost and performance. To understand the limits of materials and the change of their properties with use. To be able to create a new material that will have some desirable properties. Materials science is a broad field and can be considered to be an interdisciplinary area. This is the reason why the contributors of the chapters in this book have various fields of expertise. Therefore, this book is interdisciplinary and is written for readers with a background in physical science. I believe that this book will be of interest to university students, lecturers and researchers who are interested in the fields of materials science, engineering and technology. Due to the extent of this discipline, the book has been divided in multiple sections, each referring to a specific field of applications. The first two sections introduce the role of stoichiometry in the expanding research on nanotechnology and defect chemistry, providing few examples of state-of-the-art technologies. Section three and four are focused on intermetallic compounds and metal oxides, while section five points out the importance of stoichiometry in electrochemical applications. In section six new strategies for solid phase chemical reactions are reported, while a cross sectional approach to the influence of stoichiometry in energy production is the main topic of the last section. [...]... leading to its deformation and curvature Chrysotile, halloysite and imogolite are examples of such structures Unfortunately, Pauling concluded that layered materials with symmetric 4 Stoichiometry and Materials Science – When Numbers Matter structure, such as WS2 and MoS2, are not likely to form closed cylindrical structures It took, however, until 1992 when Tenne, Remskar and others showed that tubular... structures and to enhance their physical and chemical properties Particularly, the aluminosilicate nanostructure can be envisaged for the development of nanoreactors, 18 Stoichiometry and Materials Science – When Numbers Matter controlled release devices, ion conductors for batteries, gas storage and separation systems They are insulator and the stiffness of the NT is similar to other inorganic NTs and comparable... nanotubular particles of a 1:1 nickel phyllosilicate Microporous and Mesoporous Materials, 120, 263-266 22 Stoichiometry and Materials Science – When Numbers Matter Mukherjee, S., Bartlow, V.A & Nair, S (2005) Phenomenology of the growth of singlewalled aluminosilicate and aluminogermanate nanotubes of precise dimensions Chemistry Of Materials, 17, 4900-4909 Nakagaki, S., Castro, K., Machado, G.S.,... radius (R) and converges approximately as 1/R2, as demonstrated with SCC-DFTB calculations (Guimaraes et al., 2010) However, a detailed look at the calculated values Estr shows that they can be better fitted by the following equation (Eq 4): Estr = 49.0 3.0 − R R2 (4) 14 Stoichiometry and Materials Science – When Numbers Matter In which Estr is given in eV atom-1 and R in Å The values of 49.0 and 3.0... orthochrysotile (Whittaker, 1956b) and parachrysotile (Whittaker, 1956c) Clinochrysotile is the most common one While lizardite, more abundant than chrysotile, presents a planar shape, chrysotile presents a tubular form Chrysotile and lizardite are composed by octahedral sheet, brucite 16 Stoichiometry and Materials Science – When Numbers Matter (magnesium dihydroxide, Mg(OH)2) and tetrahedral layer tridymite... new frontiers in science and materials engineering Advanced materials are being developed with enhanced chemical and physical properties with unique characteristics The properties of these materials are determined not only by their composition and chemical bonds, but also by size and morphology The emerging field of nanotechnology is mostly focused on carbon and inorganic based nanomaterials, such as... A.N & Seifert, G (2005) Structure, stability and electronic properties of TiO2 nanostructures Physica Status Solidi B-Basic Solid State Physics, 242, 1361-1370 20 Stoichiometry and Materials Science – When Numbers Matter Enyashin, A.N., Gemming, S & Seifert, G (2007) Simulation of inorganic nanotubes Pp 3357 In S Gemming, M Schreiber, and J.-B Suck, Eds Materials for tomorrow, 93,Springer Berlin Heidelberg... Materials Science – When Numbers Matter 4 Halloysite nanotubes – Stability and structural properties Halloysite is a clay mineral normally described as a gibbsite octahedral sheet (Al(OH)3), which is modified by siloxane groups at the outer surface (figure 6), and has a 1:1 Al:Si ratio and stoichiometry Al2Si2O5(OH)4.nH2O (Guimaraes et al., 2010) Halloysite exhibits a range of morphologies, and according... the bond lengths lead to the curvature of the gibbsite layer and to the formation of the imogolite NT There is an optimal curvature which leads to the minimum strain in the structure This explains why imogolite is monodisperse with very well-defined geometrical parameters and symmetry 6 Stoichiometry and Materials Science – When Numbers Matter Fig 1 a) Periodic gibbsite layer model b) Hexagonal gibbsite... Diffraction Theoretical and General Crystallography, A 27, 659-& Yucelen, G.I., Choudhury, R.P., Vyalikh, A., Scheler, U., Beckham, H.W & Nair, S (2011) Formation of single-walled aluminosilicate nanotubes from molecular precursors and curved nanoscale intermediates Journal of the American Chemical Society, 133, 5397-5412 24 Stoichiometry and Materials Science – When Numbers Matter Zhao, M.W., Xia, . STOICHIOMETRY AND MATERIALS SCIENCE – WHEN NUMBERS MATTER Edited by Alessio Innocenti and Norlida Kamarulzaman Stoichiometry and Materials Science – When Numbers. copies can be obtained from orders@intechopen.com Stoichiometry and Materials Science – When Numbers Matter, Edited by Alessio Innocenti and Norlida Kamarulzaman p. cm. ISBN 978-953-51-0512-1. developments in nanoscience and nanotechnology opened fundamental and applied new frontiers in science and materials engineering. Advanced materials are being developed with enhanced chemical and physical