Examples of STEM images

STEM images of Pt particles in SiO₂ nanotubes
BF, ADF, and HAADF STEM images of Pt-filled SiO₂ nanotubes
In the BF-STEM image, the contrast is similar to that in BF-TEM images: Pt particles appear with dark contrast since they are crystalline and the heaviest scatterers in this system. In the ADF-STEM image, the Pt particles appear with bright contrast because of diffraction and incoherent scattering (cf., DF-TEM images). In the HAADF-STEM image, only the incoherently scattered electrons contribute to the image, which nonetheless appears to be very similar to the ADF-image.
HAADF-STEM image of Au/Pt particles on Silica
In the high-angle annular dark field (Z contrast) image, the metal particles, which have high atomic numbers Z compared to the SiO₂ matrix, are imaged as bright dots. Thus, this method is a valuable tool to investigate catalysts and to determine the sizes of metal particles and the corresponding size distribution.	Sample: Hannemann, Baiker
Structure imaging by HAADF-STEM
This HAADF-STEM image shows WO₃ segregations in a matrix of a TTB-type Nb-W oxide. The positions of the metal atom columns appear with bright contrast (c.f., HRTEM image of Nb₄W₁₃O₄₇). Oxidation Products of the Niobium Tungsten Oxide Nb₄W₁₃O₄₇: A High-Resolution Scanning Transmission Electron Microscopy Study F. Krumeich and R. Nesper J. Solid State Chem. 179 (2006) 1857-1863 DOI	Fourier-filtered HAADF-STEM image of Nb₄W₁₃O₄₇ oxidized at 1000°C. Projection along the short axis.
STEM \| Detectors \| Aberration-corrected STEM Comparison with HRTEM

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