Nanostructured materials are at the forefront of materials science because of their unique physical characteristics. To characterize its microscopic characteristics, several approaches can be used, each with its own set of advantages and disadvantages.
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Jenő Gubicza of ELTE Eötvös Loránd University in Budapest explains in an article published in The European Physical Journal Special Topics that an indirect approach, X-ray diffraction line (XLPA) profile analysis, is acceptable for analyzing nanostructured materials. , but that its application and interpretation. needs extra attention to get reliable results.
Nanostructured materials are made of grains at the nanoscale with a regular atomic lattice. “Defects”, which are sudden changes in the configurations of atoms in these lattices, give rise to useful characteristics. Researchers are able to manage the density of these defects to fine-tune the material characteristics of a nanostructure by choosing the appropriate processing conditions for nanomaterials.
XLPA examines how X-rays are diffracted by the microstructures included in the materials as they go through to compare the density of defects created by each of these procedures. The question here is whether the structural defect information acquired by XLPA is accurate, since this technology only investigates the material indirectly by X-ray scattering.
Alternatively, transmission electron microscopy (TEM) can provide extremely detailed images of these microstructures, but can only be used to analyze small volumes.
Gubicza compares the microstructures indirectly identified by XLPA with those acquired directly by TEM in his study. On the one hand, Gubicza found that the defect densities calculated by the two approaches are very similar. However, although the grain sizes determined by both approaches differ in materials with larger grain sizes, they coincided mainly for grain sizes below 20 nm.
In these situations, XLPA adequately demonstrated that both top-down and bottom-up nanomaterial processing techniques can produce high fault densities. In general, the Gubicza summary provides researchers with important information on how and when to use XLPA.
Gubicza, J. (2022) Reliability and interpretation of microstructural parameters determined by X-ray line profile analysis for nanostructured materials. The European Physical Journal Special topics. doi.org/10.1140/epjs/s11734-022-00572-z.