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SEM provides high‐resolution images of the sample surfaces [1–3, 8, 9]. It is the most popular analytical tool as it can quickly provide the detailed and good quality images of the sample. It can be coupled to an auxiliary EDS detector and provide elemental identification for most of the elements of the entire periodic table. SEM‐EDS is used where optical microscopy cannot provide sufficient image resolution of sufficient magnification. It also produces detailed surface topography images [3, 8]. Some of the advantages and limitations of SEM‐EDS are tabulated in Table 1.3.

In SEM‐EDS, the sample is scanned by the electron‐beam of the microscope and the different interactions are employed to obtain the images using secondary or backscattered electrons. Additionally, elemental analysis of the samples is performed by using the excitation of fluorescence radiation. Therefore, using the information obtained by images and elemental contents, the samples can be compared directly.

From Table 1.1, it is clear that μ‐XRF and SEM‐EDS possess different spatial resolutions and also have some differences for elemental detection [3, 8]. However, the main differences exist in terms of specific sample handling and some analytical capabilities.