Combining ADF STEM atom-counting with atomistic modelling for improved catalyst design.
Designing nanomaterials requires understanding their structures at the atomic-scale, but this first requires imaging samples at extremely high-resolution. The scanning transmission electron microscope (STEM) can deliver this performance and provide mass and composition information at the atomic scale. Below is an example of a movie from this type of microscope showing a platinum nanoparticle.
This movie was recorded using an aberration corrected annular dark-field STEM at a rate of ~10 seconds per frame (best viewed fullscreen to see the individual atoms). The frames were then compensated for image drift and distortion using the Smart Align software.
After realignment and distortion compensation, the clearly-oriented left-hand half of the particle was analysed to count the number of atoms and to rebuild 3D atomic models. The image at the top of this page is a rotated view of the first frame of the movie. Full detail about the analysis procedure can be found in the full length paper.