MATERIALS CHARACTERIZATION
Thus far, we have focused on the relationship between the structure of a material
and its properties/applications. However, we have not yet focused on how one is able
to determine the structure and composition of materials. That is, when a material is
fabricated in the lab, how are we able to assess whether our method was successful?
Depending on the nature of the material being investigated, a suite of techniques may
be utilized to assess its structure and properties. Whereas some techniques are qualitative,
such as providing an image of a surface, others yield quantitative information
such as the relative concentrations of atoms that comprise the material. Recent
technological advances have allowed materials scientists to accomplish something
that was once thought to be impossible: to obtain actual two-dimensional/threedimensional
images of atomic positions in a solid, in real time. It should be noted
that the sensitivity of quantitiative techniques also continues to be improved, with
techniques now being able to easily measure parts per trillion (ppt) concentrations of
impurities in a bulk sample.
This chapter will focus on the most effective and widely used techniques available
to characterize solid-state compounds. The primary objective of this chapter
is to provide a practical description of the methods used to characterize a broad
range of materials. Rather than focusing on the theoretical aspects of each technique,
which may be found in many other textbooks (see “Further Reading” section),
our treatment will focus on method suitabilities, sample preparation, and anticipated
results. In this manner, you will be well informed regarding the best method to use
for a particular material. Since techniques such as solution-phase nuclear magnetic
resonance (NMR) and infrared spectroscopy (IR) are used throughout undergraduate
courses, the background of these methods will not be provided in this textbook.
Likewise, it is beyond the scope of this chapter to provide detailed background in
optics, electronics, and physical chemistry concepts that underly most of the techniques
described herein. For this information, the reader is referred to the “Further
Reading” section at the end of this chapter.