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- Herausgeber: Wiley-VCH GmbH
- Kategorie: Fachliteratur
- Sprache: Englisch
Practical Guide to Materials Characterization
Practice-oriented resource providing a hands-on overview of the most relevant materials characterization techniques in chemistry, physics, engineering, and more
Practical Guide to Materials Characterization focuses on the most widely used experimental approaches for structural, morphological, and spectroscopic characterization of materials, providing background, insights on the correct usage of the respective techniques, and the interpretation of the results. With a focus on practical applications, the work illustrates what to use and when, including real-life examples showing which characterization techniques are best suited for particular purposes. Furthermore, the work covers the practical elements of the analytical techniques used to characterize a wide range of functional materials (both in bulk as well as thin film form) in a simple but thorough manner.
To aid in reader comprehension, Practical Guide to Materials Characterization is divided into eight distinct chapters. To set the stage, the first chapter of the book reviews the fundamentals of materials characterization that are necessary to understand and use the methods presented in the ensuing chapters. Among the techniques covered are X-ray diffraction, Raman spectroscopy, X-ray spectroscopy, electron microscopies, magnetic measurement techniques, infrared spectroscopy, and dielectric measurements.
Specific sample topics covered in the remaining seven chapters include:
- Bragg’s Law, the Von Laue Treatment, Laue’s Equation, the Rotating Crystal Method, the Powder Method, orientation of single crystals, and structure of polycrystalline aggregates
- Classical theory of Raman scattering, quantum theory of Raman spectroscopy, high-pressure Raman spectroscopy, and surface enhanced Raman spectroscopy
- Basic principles of XAS, energy referencing, XPS spectra and its features, Auger Electron Spectroscopy (AES), and interaction of electrons with matter
- Magnetization measuring instruments, the SQUID magnetometer, and the advantages and disadvantages of vibrating sample magnetometer (VSM)
With comprehensive and in-depth coverage of the subject, Practical Guide to Materials Characterization is a key resource for practicing professionals who wish to better understand key concepts in the field and seamlessly harness them in a myriad of applications across many different industries.
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Veröffentlichungsjahr: 2022
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Practical Guide to Materials Characterization
Techniques and Applications
Khalid Sultan
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Dr. Khalid SultanCentral University of KashmirDepartment of PhysicsGanderbal, Jammu and Kashmir191131 SrinagarIndia
Cover image© marigold_88/Getty Images
List of Tables
CHAPTER 02
Table 2.1 Structural lattice...
Table 2.2 Various lattice...
Table 2.3 Structural parameters...
CHAPTER 03
Table 3.1 Raman modes...
Table 3.2 The observed...
Table 3.3 Ionic radii...
CHAPTER 04
Table 4.1 Atomic orbital...
CHAPTER 06
Table 6.1 Dependence of...
CHAPTER 07
Table 7.1 Surface roughness...
Table 7.2 EDAX of...
CHAPTER 08
Table 8.1 Degrees of...
Table 8.2 Infrared bands...
List of Illustrations
CHAPTER 01
Figure 1.1 The electromagnetic spectrum...
Figure 1.2 A two-dimensional...
Figure 1.3 Representation of in...
Figure 1.4 Example showing directions...
Figure 1.5 Two-dimensional Bravais...
Figure 1.6 Simple cubic Bravais...
Figure 1.7 Crystal systems.
CHAPTER 02
Figure 2.1 Scattering of X...
Figure 2.2 Diffraction of X...
Figure 2.3 Scattering from two...
Figure 2.4 Geometrical interpretation of...
Figure 2.5 Geometry of an...
Figure 2.6 Arrangement of various...
Figure 2.7 A peak in...
Figure 2.8 Arrangement of a...
Figure 2.9 XRD pattern of...
Figure 2.10 Crystal rotation axes...
Figure 2.11 Plotting method applied...
Figure 2.12 Back-reflection patterns...
Figure 2.13 Influence of the...
Figure 2.14 XRD print of...
Figure 2.15 Lattice constants as...
Figure 2.16 XRD pattern of...
Figure 2.17 Lattice constants a...
Figure 2.18 Rietveld treatment of...
CHAPTER 03
Figure 3.1 Mechanism of infrared...
Figure 3.2 Experimental setup for...
Figure 3.3 Energy levels in...
Figure 3.4 Representation of energy...
Figure 3.5 Depiction of the...
Figure 3.6 An arrangement of...
Figure 3.7 Schematic arrangement of...
Figure 3.8 Resonance Raman spectroelectrochemistry...
Figure 3.9 Resonance Raman spectroelectrochemistry...
Figure 3.10 Raman spectra of...
Figure 3.11 Raman spectra of...
Figure 3.12 Raman spectra of...
Figure 3.13 Raman spectra of...
Figure 3.14 Variation of the...
Figure 3.15 Variation of the...
Figure 3.16 Variation of FWHM...
CHAPTER 04
Figure 4.1 Representation of a...
Figure 4.2 Different phenomena when...
Figure 4.3 Schematic of the...
Figure 4.4 Transition of an...
Figure 4.5 Normalized absorption vs...
Figure 4.6 Representation of the...
Figure 4.7 Transitions that contribute...
Figure 4.8 Modern synchrotron facility...
Figure 4.9 A modern XAS...
Figure 4.10 The experimental setup...
Figure 4.11 (a) Normalized O...
Figure 4.12 (a) Normalized Mn...
Figure 4.13 NEXAFS spectra for...
Figure 4.14 Difference spectra for...
Figure 4.15 NEXAFS spectra for...
Figure 4.16 NEXAFS spectra of...
Figure 4.17 A model atom...
Figure 4.18 The process that...
Figure 4.19 XPS instrument schematic...
Figure 4.20 Schematic diagram of...
Figure 4.21 (a) A wide...
Figure 4.22 Variation of yield...
Figure 4.23 (a) Knock-out...
Figure 4.24 (a) Electron is...
Figure 4.25 (a) Relaxation process...
Figure 4.26 Distribution of energy...
Figure 4.27 Differentiated and direct...
Figure 4.28 Auger electron spectroscopy...
CHAPTER 05
Figure 5.1 Arrangement for measuring...
Figure 5.2 Schematic arrangement for...
Figure 5.3 Schematic arrangement of...
Figure 5.4 Schematic arrangement of...
Figure 5.5 A substance in...
Figure 5.6 Rod-shaped magnetic...
Figure 5.7 ZFC and FC...
Figure 5.8 Magnetization in terms...
Figure 5.9 Magnetization as a...
Figure 5.10 Magnetization in terms...
Figure 5.11 Field dependence of...
CHAPTER 06
Figure 6.1 Polarization mechanism...
Figure 6.2 Electronic polarization of...
Figure 6.3 Orientational polarization.
Figure 6.4 Frequency dependence of...
Figure 6.5 Within the alternating...
Figure 6.6 Buildup of polarization...
Figure 6.7 Frequency dependence of...
Figure 6.8 Dielectric constant as...
Figure 6.9 Dielectric loss as...
Figure 6.10 Dielectric constant at...
Figure 6.11 Frequency dependence of...
Figure 6.12 Frequency dependence of...
Figure 6.13 Dielectric constant as...
Figure 6.14 Temperature dependence of...
Figure 6.15 The AC conductivity...
CHAPTER 07
Figure 7.1 Geometry of a...
Figure 7.2 Interaction of an...
Figure 7.3 There are two...
Figure 7.4 An X-ray...
Figure 7.5 Electron spectrum showing...
Figure 7.6 The family of...
Figure 7.7 Schematic diagram of...
Figure 7.8 STXM images of...
Figure 7.9 Early photograph of...
Figure 7.10 The first commercial...
Figure 7.11 Two recent TEMs...
Figure 7.12 TEM diffraction-contrast...
Figure 7.13 TEM image (right...
Figure 7.14 A 3 MV...
Figure 7.15 SEM at the...
Figure 7.16 HITACHI-SU5000 SEM...
Figure 7.17 Photograph of the...
Figure 7.18 Atomic columns in...
Figure 7.19 Elements of an...
Figure 7.20 AFM image of...
Figure 7.21 Shows 1...
Figure 7.22 Shows 1...
Figure 7.23 The SEM and...
CHAPTER 08
Figure 8.1 Michelson interferometer...
Figure 8.2 Synchronization of the IR...
Figure 8.3 Optical schematic of...
Figure 8.4 H2O and CO2...
Guide
Cover
Title page
Copyright
Table of Contents
List of Figures
List of Tables
Preface
Begin Reading
Index
End User License Agreement
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List of Tables
Table 2.1 Structural lattice parameters of the PrFe1–xMnxO3 system.
Table 2.2 Various lattice parameters in the La1–xCaxMnO3 system.
Table 2.3 Structural parameters and activation energy for EFMO.
Table 3.1 Raman modes along with the corresponding atomic motion for PrFeO3.
Table 3.2 The observed Raman modes with corresponding assignments.
Table 3.3 Ionic radii of the constituent elements of La1–xCaxMnO3.
Table 4.1 Atomic orbital nomenclature.
Table 6.1 Dependence of various parameters on concentration x of Mn in PFMO.
Table 7.1 Surface roughness and grain diameter.
Table 7.2 EDAX of EuFe1–xMnxO3.
Table 8.1 Degrees of freedom in linear and nonlinear molecules.
Table 8.2 Infrared bands of major food components.
Preface
Characterization of materials is the measurement and determination of a material’s physical, chemical, mechanical, and microstructural properties. This technique provides the greater degree of awareness required to handle significant issues such as failure causes and process-related concerns, as well as allowing the manufacturer to make critical material decisions. The field of materials characterization is vast and diverse. Perhaps the best place to begin is at the beginning, with the first principle to consider being the depth to which characterization promotes the discovery of new materials:
Measuring a material’s property allows for experimental improvement;
Taking unique measurements allows for distinction through improvement in specific areas; and
Understanding the compositional and structural foundations of material attributes allows for rationally designed improvements.
Material characterizations is a crucial step to conduct before using the materials for any purpose. To ensure that the material under consideration can perform without failure during the life of the final product, it might be subjected to mechanical, thermal, chemical, optical, electrical, and other characterizations, depending on the purpose.
This book focuses on the most extensively used experimental approaches for structural, morphological, and spectroscopic characterization of materials. One of the most important aspects of this book is the discussion of recent results in a wide range of experimental techniques and their application to the quantification of material properties. Furthermore, it covers the practical elements of the analytical techniques used to characterize a wide range of functional materials (both in bulk as well as thin film form) in a simple but thorough manner. For a wide range of readers, from beginners and graduate students to expert specialists in academia and industry, the book gives an overview of frequently used characterization approaches. One of my main aims in preparing this book was to put the basic characterizations used by material research students in the form of a single book. The book is divided into eight chapters.
The first chapter gives the basic ideas of an electromagnetic spectrum, which is important as properties of materials are obtained using the interaction of light with matter. In addition, some fundamentals of crystallography, the magnetic materials, the molecular vibrations, and optical properties in materials have been defined. The second chapter is based on the one and foremost technique used in material sciences and is called the X-ray diffraction technique. After synthesis of any material, the first step is confirmation, which is obtained through the X-ray diffraction pattern. The basic theory, the experimental setup, along with some examples and applications have been included in this chapter. Chapter 3 concerns Raman spectroscopy. In addition to the X-ray diffraction technique, Raman spectroscopy may also be used for the identification of samples. In this chapter, basic theory, the instrumentation of Raman spectrometer, and illustrations are included. Chapter 4 discusses X-ray spectroscopic techniques. Three techniques, namely X-ray absorption spectroscopy, X-ray photoemission spectroscopy, and Auger electron spectroscopy have been explained along with the basic principle and experimental setup for each case.
In Chapter 5 magnetism in solids has been incorporated along with the methods of magnetic measurements. Three important methods, like the extraction technique, vibrating sample magnetometer, and SQUID, are part of this chapter. Moreover, some examples for the measurement of magnetic properties, like temperature dependence of magnetization and field dependence of magnetization in some particular compounds, have been set up to give a clearer picturization of magnetic measurements. Chapter 6 refers to dielectric measurements. A fundamental description has been set up for dielectric properties before explaining the different trends of the dielectric constant and dielectric loss as a function of temperature and as a function of frequency. Alternating current conductivity is also part of this description. Chapter 7 discusses electron microscopy in material sciences where the scanning electron microscope, transmission electron microscope, scanning transmission electron microscopy, X-ray microscope, and atomic force microscopy are described in detail. Moreover, some examples of atomic force microscopy and scanning electron microscopy pertaining to some particular compounds form part of this chapter. Finally, the last chapter of book is on infrared spectroscopy. In this chapter the theory of infrared spectroscopy has been included along with instrumentation. Fourier transform infrared spectroscopy has also been explained. Lastly, some applications of infrared spectroscopy in our day-to-day life form part of this chapter.
1 Basics of Material Characterization Techniques
1.1 Introduction
In our daily life we come across different types of materials like metals, semiconductors, and ceramics. Scientific communities are continually exploring the nature of materials as well as their technological use, which requires understanding of some of the basic principles of physics and chemistry. The foremost thing about a material that is to be investigated is its structure and the related properties. The material is then fabricated to such a design that it results in exceeding the basic technological requirements. Checking the performance of the material is always a major focus in order to observe the behavior of the material under different conditions. The synthesis and characterization of materials play a crucial role for materials, research and nowadays a number of advanced instruments are available to understand the large range of mechanisms in materials. Since all characterization techniques are fundamental pillars in understanding the properties of a material, each characterization technique is based on some basic principles and some basic processes of physics. It is therefore worthwhile outlining the principles and processes that are being applied or used by different characterization techniques. Most characterization techniques involve the use of electromagnetic light, so information about the electromagnetic spectrum and related processes like reflection, refraction, absorption, transmittance, diffraction, interference, and dispersion are part of this chapter.
Apart from this, the solid form of materials is the most stable form, with minimum free energy, and a detailed information about the crystallography is provided, which is beneficial for understanding the structural properties of materials using techniques like X-ray diffraction. These are followed up in subsequent chapters. Similarly, different kinds of molecular motion and vibrations are also present in solids that, using Raman spectroscopy and infrared spectroscopy, also provide information about the materials providing information about the different motion in solids that form the initial stage for obtaining information and data. Some techniques such as electron microscopy also make use of electrons. This chapter provides details about electron–matter interactions and related consequences providing the morphology, topography, elemental composition, etc. Apart from these structural studies, dielectric studies of materials involve terms like dielectric constant and dielectric loss, which are also important parameters. The magnetic phenomenon involves magnetic terms and types of magnetism. All these terms are defined within this book.
1.2 Electromagnetic Spectrum
The electromagnetic spectrum envelops electromagnetic waves with a wide range of frequencies and hence a wide range of wavelengths and energy. The frequency range is divided into various parts and electromagnetic waves in each part have different names. Going from the low-frequency end of the electromagnetic spectrum to the high-frequency end we have radio waves, microwaves, infrared, visible light, ultraviolet (UV), X-rays, and gamma rays. Each type has different characteristics of production, interaction, and applications. Gamma rays, X-rays, and high-energy UV are called ionizing radiations because their photons have energy to ionize an atom. Some of the frequencies are responsible for spectroscopy, which is also based on the interaction of electromagnetic waves with matter. Before the 1800s, the term “light” was interpreted by a general reader and even a specialized person as visible light. In the 1800s, it was found that light contains not only the visible part but something more as evidenced by William Herschel’s discovery of infrared light. The infrared region has three main parts, i.e., the far infrared, the mid-infrared, and the near infrared. The near-infrared region lies at the visible end of the electromagnetic spectrum. Similarly, in 1801 Johann Ritter identified the part of the spectrum that lies just beyond the violet end of visible light, which he termed deoxidizing rays. In the late ninetenth century, knowledge of these rays was well established and they were termed the UV rays. The UV region also consists of several parts, i.e., long-wave UV, medium-wave UV, and short-wave UV. James Clark Maxwell’s equations provided information about the existence of an infinite number of frequencies of electromagnetic waves and thus predicted the entire electromagnetic spectrum. Heinrich Rudolf Hertz was the first to generate radio waves and microwave radiation. The study of X-rays was first carried out by Wilhelm Röntgen in 1895. X-ray spectroscopy was developed by Karl Manne Siegbahn, who was then awarded the 1924 Nobel Prize in Physics for his work. The discovery of gamma rays was made by Paul Villard in 1900 during an investigation of radioactivity and was said to be electromagnetic radiation, with the shortest wavelength and hence the highest energy as well as frequency. All parts of the spectrum are important and, as a result of their different characteristics, are used in different spectroscopic techniques [1]. The electromagnetic spectrum is shown in Figure 1.1.
Figure 1.1 The electromagnetic spectrum.
Thus, based on the frequency, wavelength, and energy, which are fundamental factors in the spectrum, the electromagnetic radiations are divided into the following classes, regions, or bands:
gamma radiation,
X-ray radiation,
UV radiation,
visible radiation,
infrared radiation,
microwave radiation, and
radio waves.
These regions are given in increasing order of wavelength. It should also be noted that there is no well-defined boundary between the regions and they fade into each other.
Radio waves: These waves are released or received by antennas. The production of these waves involves the generation of an alternating current (AC) by a transmitter, which is an electric device available with an antenna. There is generation of oscillating electric and magnetic fields due to the oscillations of electrons in the antenna that lead to radiations that leave the antenna in the form of radio waves. Receiving these radio waves is associated with the coupling of oscillating electric and magnetic fields of waves with the electrons in the antenna. This causes the back-and-forth movement of electrons, thereby producing oscillating currents that are applied to radio receivers. These waves are used in the transmission of information in communication systems and in the Global Positioning System (GPS).
Microwaves: These waves are absorbed by polar molecules in addition to being released and received by short antennas. These are considered as radio waves of short wavelength with the characteristic of being used in radars and satellites. Microwaves have the capability to penetrate a material in order to deposit the energy well inside the surface. As a result they are used in microwave ovens.
Infrared radiation: The range of this frequency of radiation is approximately from 300 GHz to 400 THz. The far infrared part, ranging from 300 GHz to 300 THz, lies towards the microwave edge and is absorbed by the rotational modes of gas, the molecular motions in liquid, and phonons in solids. These are strongly absorbed by the water available in the atmosphere of Earth so are opaque to them, but there are certain frequencies that are allowed and are under study by astronomers. The mid-infrared part ranges from 30 THz to 120 THz. The hottest object or a blackbody radiator can emit radiations in this range while the skin of human beings also emits radiations of frequencies lying towards the lower end of this mid-region. As far as absorption of these radiations is concerned, they are absorbed by the vibration of molecules. The near-infrared part of this region ranges from 120 THz to 400 THz and lies towards the visible part of the electromagnetic spectrum. The higher frequencies are usually detected by photographic films and image sensors.
Visible light: The range of this frequency of radiations is approximately from 400 THz to 790 THz. This part of the electromagnetic spectrum is visible to human eyes and hence is called visible light. It is released and absorbed by electrons in an atom or in a molecule when going from one energy level to another. A rainbow shows the visible part of the electromagnetic spectrum, consisting of seven colors.
UV radiation: The wavelength range of these radiations of the electromagnetic spectrum is less than the visible part, but is considered to have the longest wavelength, with photons having such energy that they can ionize atoms. Shorter wavelength UV radiation and radiations having still smaller wavelengths, like X-rays and gamma rays, are known as ionizing radiations. UV also causes certain materials to glow, producing visible light, and the phenomenon is known as fluorescence.
X-ray: This is radiation that can interact with matter through the Compton effect. X-rays can be hard X-rays and soft X-rays, differing by the kind of wavelength. Shorter wavelength X-rays are called hard X-rays and can easily pass through different materials along with some absorption. The one most important use of these radiations is in diagnostic imaging. In material sciences, the X-rays diffraction phenomena has a major role in the identification of different compounds and samples. As far as the production of X-rays is concerned, they are released when there is a sudden deceleration of fast-moving electrons while interacting with the target anode.
Gamma rays: Gamma rays have the shortest wavelengths and were, discovered by Paul Ulrich Villard. These are considered to have the most energetic radiation, with no lower limit for their wavelength, and are usually used in the irradiation of food and seeds. In the field of astronomy these radiations have a role in the investigation of high-energy regions.
1.3 Fundamentals of Crystallography
The state of matter in which there is a regular arrangement of atoms is referred to as solid and the regularity is expressed by symmetry elements. In modern times the regularity of atoms can be studied with the help of high-resolution transmission electron microscopy. The arrangement and pattern of atoms connected through various interatomic forces can be expressed in terms of a unit whose repetition gives rise to crystals. In crystals, the set of points surrounding any given point is identical to those of all other points and constitutes a lattice, where each point is called a lattice point. A lattice in a crystal describes a translational symmetry. In the case of three dimensions, the unit cell is in the form of a parallelepiped such that the origin lies at the corner of the unit cell and the three axes are represented in terms of sides of the unit parallelepiped. The three axes are connected with each other through angles α, β, and γ, and the minimum separation between two adjacent lattice points along the three axes is expressed in terms of lattice parameters x, y, and z.
Consider a two-dimensional crystal having lattice parameters a and b such that the magnitudes of both a and b are different, as shown in Figure 1.2, where we observe that the mesh lines OB, O′B′, and O′′B′′ are parallel and thus constitute a set with regular spacing in between these mesh lines. Similarly, the same effect can be observed in mesh lines AB, A′B′, and A′′B′′. It has been determined that the spacing between parallel mesh lines depends not only on the lattice parameters a and b vectors but also on the angle between the a and b vectors. However, the case of the angle between the two sets depends on the ratio of magnitude of a and b. It should be noted that the value of the angle between the corresponding faces is constant as long as all the crystals are of the same substance [2]. In this analogy of lines in a mesh, in the planes of a crystal the faces of the crystal are parallel to the planes of the lattice and the lattice planes have a high density. In this case, we also have a set of parallel planes whose spacing depends on the lattice parameters and axial angles. However, the angle between various lattice planes depends on the ratio of the axial angles and lattice parameters.
Figure 1.2 A two-dimensional crystal.
In a crystal the direction is expressed as a line. Let us assume two points P and P′ lying on a line with P at the origin, as shown in Figure 1.3. Using the concept of translation, the vector r joining P and P′ can be expressed in terms of a, b, and c vectors along the x, y, and z directions, respectively, as
Figure 1.3 Representation of r in terms of a, b, and c.
The notation for direction is then represented by arrows and examples are shown in Figure 1.4.
Figure 1.4 Example showing directions.
In cases where the value of any of the u, v, and w is negative, it is expressed in terms of bar. Moreover, P lies at the origin and in the case where u, v, and w
