Introductory Chapter: Materials Analysis by Using Electronic Microscopes and Spectroscopy

1. Introduction

Materials analysis plays a pivotal role in understanding the properties, behavior, and performance of various substances, from the smallest nanoparticles to the largest engineering structures. The advent of electronic microscopes and spectroscopic techniques has revolutionized the field of materials science, enabling researchers to delve deeper into the atomic and molecular structure of materials with unprecedented precision and detail [1].

1.1 Applications of some analysis techniques using electronic microscopes

Material analysis using electron microscopy techniques involves the study of materials at a microscopic level with high resolution and magnification. Electron microscopes use a beam of accelerated electrons to illuminate the sample, providing detailed images of the material’s surface and internal structure. These techniques, such as scanning electron microscopy (SEM) and transmission electron microscopy (TEM), allow researchers to visualize the morphology, composition, and crystallographic information of materials at nanoscale dimensions. Electron microscopy plays a crucial role in various scientific disciplines, including materials science, nanotechnology, biology, and geology, enabling a deeper understanding of the properties and behavior of diverse materials [2]. In the case of materials processing analysis, atomic force microscopy (AFM) has been used to review the profile of the treated surface, as shown in (Figure 1) [3].

Figure 1.

AFM images of a cavity generated by photochemical etching in a GaSb sample with (a) a 1 M HCl solution having root mean square (RMS) roughness of 57 nm; and (b) in a 0.2 M H2SO4 solution, having an RMS roughness of 11 nm [3].

In Ref. [4], a guide on designing electron microscopes for material characterization is presented, focusing on the benefits of utilizing backscattered electrons (BSE), secondary electrons (SE), and energy-dispersive spectroscopy (EDS). The approach includes discussions on incorporating additional microscopy techniques like atomic force microscopy (AFM), ellipsometry, and optical profilometry as supplementary methods to validate electron microscopy findings. Applications showcased encompass eutectic alloys, thermal oxides, and nanoparticles across various industries [5]. Trace evidence analysis is crucial in criminal investigations as it offers critical information for linking suspects to crime scenes. In forensic investigations, SEM is a vital tool, particularly in gunshot residue (GSR) analysis, where SEM helps match bullets to firearms more effectively than visual methods. Moreover, SEM is significant in examining gemstones and jewelry by distinguishing between natural and synthetic gems, studying surface flaws, and identifying elemental compositions [6]. In Ref. [7], the importance of using SEM coupled with X-ray energy dispersive (SEM-EDX) to analyze the surface of kidney stones for evaluating the antilithiatic properties of extracts from medicinal plants like Saussurea costus (Falc) Lipsch is emphasized. This highlights the significant role of electron microscopy in medical research, with a focus on urinary lithiasis.

1.2 Applications of some analysis techniques using spectroscopy

In a similar way and as complementary analysis, spectroscopy techniques provide valuable information about the composition, structure, and properties of materials by analyzing the way they absorb, emit, or scatter light. These techniques allow researchers to identify substances, determine their concentration, and understand their molecular and atomic structure [8]. By examining the unique spectral fingerprints of materials, spectroscopy plays a crucial role in various scientific fields, including chemistry, physics, biology, and materials science.

The fusion of ion mobility spectrometry with mass spectrometry (MS), referred to as an IM-MS hybrid instrument, provides improved analytical separation and identification abilities that have greatly progressed fields such as biomedical, pharmaceutical, and forensic sciences. In Ref. [9], a thorough examination of different IMS instrument platforms is presented, which includes traveling wave (TWIMS), drift tube (DTIMS), trapped (TIMS), differential mobility analyzer (DMA), and field asymmetric waveform (FAIMS). The identification of biomarkers through MS is crucial in clinical medical research. Yet, analyzing proteins in formalin-fixed paraffin-embedded (FFPE) samples using MS has been difficult due to decreased solubility from fixation, resulting in crosslinking reactions among amino acid side chains in proteins. In Ref. [10], various methods used for omics analysis of FFPE samples to discover disease-specific biomarkers are discussed. Spectroscopy in predictive genomics has the ability to assist in treatment decisions by allowing individuals to take proactive measures to prevent serious illnesses. For matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS technology identifies genetic variations based on their unique mass [11]. Apart from pharmacogenetics, SNP variations are important in various medical fields. The importance of different SNPs in nutrigenetics is addressed in Ref. [12].

This introductory chapter provides a short but comprehensive understanding about electronic microscopes and spectroscopy as powerful tools for materials analysis, its sections address specific aspects of the topic. The content covers the principles underlying electron microscopy and spectroscopy, the various imaging and analytical modes available, sample preparation techniques, data interpretation and analysis, as well as a diverse range of applications spanning different material classes. Furthermore, the book will delve into recent advancements and emerging trends in the field, shedding light on the future prospects of materials analysis using electronic microscopes and spectroscopy. In summary, this introductory chapter sets the stage for an in-depth exploration of electronic microscopes and spectroscopy as indispensable tools for materials analysis. By elucidating their historical evolution, significance, and the scope of this book, it aims to provide a solid foundation for readers to embark on a comprehensive journey through the world of advanced materials characterization.