Nano-Beam X-Ray Nanodiffraction (2D n-XRD)
Nano-Beam X-Ray Nanodiffraction (2D n-XRD) stands at the forefront of material characterization, offering insight into the crystallographic complexities of materials on the nanoscale. This advanced analytical technique utilizes a focused X-ray beam to meticulously investigate nanometer-sized regions within a sample. By capturing a two-dimensional diffraction pattern, 2D n-XRD provides researchers with a detailed understanding of the crystalline structures present, offering insights into phase composition, strain distribution, and orientation mapping at a level of spatial resolution that was previously unattainable. Positioned at the intersection of nanoscience, materials engineering, and condensed matter physics, 2D n-XRD serves as a crucial tool for unraveling the unique properties and behaviors of nanomaterials, paving the way for innovations in semiconductor technology, nanoelectronics, and the tailored design of novel nanomaterials.
As 2D n-XRD continues to push the boundaries of materials research, its applications extend beyond traditional domains, promising breakthroughs in our ability to manipulate and engineer materials at the nanoscale. The precision afforded by this technique holds great potential for advancements in various industries, offering researchers a powerful means to explore and harness the properties of nanomaterials for diverse applications. With its ability to provide detailed structural information with nanoscale resolution, 2D n-XRD is poised to play a pivotal role in shaping the future of materials science and nanotechnology.
Solar Cell
The investigation delves into the structural analysis of spin-coated CH3NH3PbI3 (MAPI) perovskite films across varying deposition temperatures, meticulously scrutinized using scanning nano focus X-ray diffraction (nXRD) techniques. Noteworthy findings reveal consistent scattering patterns across samples subjected to different processing temperatures (cold, medium, and hot) as depicted in Figure 1. Through meticulous analysis of azimuthally integrated line profiles extracted from the average diffraction patterns, a pivotal observation emerges: the merging of (002) and (110) reflections into a single peak at temperatures exceeding 54–57 °C, indicative of the transition from the tetragonal to the cubic phase. Moreover, lattice parameter assessments align with prior research, affirming the persistence of the β-phase MAPI crystals across the temperature spectrum under investigation. These revelations underscore the robustness of the perovskite film's crystal structure, despite the varied processing temperatures, offering valuable insights for the optimization of perovskite-based photovoltaic devices.
Reference:
Lilliu, S., Dane, T.G., Alsari, M., Griffin, J., Barrows, A.T., Dahlem, M.S., Friend, R.H., Lidzey, D.G. and Macdonald, J.E. (2016), Mapping Morphological and Structural Properties of Lead Halide Perovskites by Scanning Nanofocus XRD. Adv. Funct. Mater., 26: 8221-8230.
https://doi.org/10.1002/adfm.201603446
Steel Corrosion Study
In this study, a chemical cell was designed to analyze the phases formed during corrosion when a chlorinated solution is introduced near the iron bar. One hour into the experiment (Figure 2), chlorinated green rust is the main substance near the rod, with sporadic spots of akaganeite. After 4 hours, similar observations persist, with increased intensities and expansion of the green rust zone. By 8 hours, akaganeite forms locally near the rod, and both substances become more concentrated. Goethite starts appearing farther from the rod. Interestingly, during the experiment, the area dominated by akaganeite shifts on the rod's surface, possibly due to adhesive peeling. After 20 hours, green rust diminishes, while akaganeite remains near the metal and goethite appears at a greater distance. By 32 hours, green rust vanishes completely, and the system stabilizes. Subsequent maps reveal goethite presence from 0.6 to 1.6 millimeters from the rod, indicating coexistence of chlorinated green rust, akaganeite, and goethite at different distances from the metal/binder interface.
Reference:
S. Grousset, F. Kergourlay, D. Neff, E. Foy, J.-L. Gallias, S. Reguer, P. Dillmann and A. Noumowé, J. Anal. At. Spectrom., 2015, 30, 721.
https://doi.org/10.1039/C4JA00370E
Soil Crusting Study
Initial micromorphological insights derived from the 2D-µXRD map involve mapping clay minerals using hk bands and quartz intensities. Figure 3a unveils significant heterogeneity in the spatial distribution of clay phases, aligning with sequential depositional events. The presence of a thin clayey microlayer at the base of the sedimentary crust identified through SEM analyses, is confirmed on the 2D-µXRD maps by the increased Ihk values (clay microlayer A at the transition between zone 1 and 2 in Figure 3a and 3c). The boundary between the denser structural crust and the sedimentary crust, where the thin clayey layer is situated, is also highlighted by the distinct contrast on the resin map (Figure 3d). Notably, while the Ihk map confirms the clay-rich composition of micro aggregates in zone 3 (clay microlayer C; Figure 3c), the method identifies two additional thin clay microlayers (clay microlayer B and D; Figure 3c) that are not discernible from SEM analyses.
Reference:
Vincent Geoffroy, Baptiste Dazas, Eric Ferrage, Felisa Berenguer, Céline Boissard, Laurent J. Michot, Folkert van Oort, Emmanuel Tertre, Fabien Hubert, Soil crusting: New insight from synchrotron 2D micro X-ray diffraction mapping of clay-particle orientation and mineralogy, Geoderma, 428, 2022, 116096.
https://doi.org/10.1016/j.geoderma.2022.116096.
Polycrystalline Metal
The evolution of lattice orientation and stress under tensile loading is examined. Figures 4(a) and 4(b) depict the orientation maps before and after 2.4% plastic strain, respectively. Despite deformation, the grain structure remains identifiable, with similar lattice orientations due to the modest plastic strain applied. However, the number of unindexed patterns slightly increases with deformation, attributed to broadening and fragmentation of Laue spots. Figures 4(c) and 4(d) display the Schmid factor maps before and after deformation, respectively. Higher Schmid factors indicate favorable slip orientations, while lower Schmid factors suggest harder grains. After deformation, grains with lower Schmid factors exhibit lower fitting errors, implying less spreading and fragmentation of Laue spots. Maps of the axial stress component (x-direction) before and after deformation (Figures 4(e) and 4(f)) reveal a clear increase in stress values with deformation. Grains with lower Schmid factors show higher stresses, contrary to the simplistic Schmid model. This indicates that load sharing between multiple grains in a polycrystal is not fully explained by the Schmid model alone.
Reference:
Hofmann, F., Song, X., Abbey, B., Jun, T.-S. & Korsunsky, A. M. (2012). High-energy transmission Laue micro-beam X-ray diffraction: a probe for intra-granular lattice orientation and elastic strain in thicker samples. J. Synchrotron Rad. 19, 307-318.
https://scripts.iucr.org/cgi-bin/paper?s0909049512003044