XRD tomography

Progress in nano sciences requires further development of local structural probes, particularly for the study of non-uniform materials. As material functions are often concerned with heterogeneity and some hierarchical orders of the structures, some kind of zooming from low to high resolution will become crucial in the future. Furthermore, in addition to two-dimensional (2D) imaging of an object with a lateral resolution determined by the beam size, some depth resolution is important for a better understanding of materials. So far, X-ray techniques have had several limitations with respect to such points. Recently, French scientists led by Professor J-L. Hodeau (CNRS, Grenoble, France) have reported an interesting development. They are trying to combine pencil-beam tomography with X-ray diffraction to examine unidentified phases in nanomaterials and polycrystalline materials. The experiments were for a high-pressure pellet containing several carbon phases and a heterogeneous powder containing chalcedony and iron pigments. For more information, see the paper, "Probing the structure of heterogeneous diluted materials by diffraction tomography", P. Bleuet et al., Nature Materials, 7, 468 (2008).