Figure 4: 3D structure, elemental mapping and elemental-association data for completely oxidized particles.
From: Interrogation of bimetallic particle oxidation in three dimensions at the nanoscale
(a) 3D structure of a Type I particle, with a solid shell and large hollow volume fraction (44.79%). (b) 3D structure of a Type II particle, which has a nanoporous shell and small hollow volume fraction (11.52%) when compared with (a). (c) 3D elemental distribution after removing plural scattering. (d,e) Sequential cross sections and 3D rendering of the Ni and Co color-mixed map and HAADF-STEM map, respectively. Comparing (d) with (e) illustrates that a large number of Co element nanodomains are spatially separated from Ni and are concentrated on the outside of the shell and around the holes. Scale bar, 50 nm. (f) The fractional distribution of Co voxel counts in Co and Ni. (g) The relative concentrations of 3D elemental associations. (h) Elemental distribution as a function of the distance from nanosphere center calculated using 3D STEM-EELS data.
