Three-dimensional analysis of nanoparticles on carbon support using aberration-corrected scanning confocal electron microscopy

We observed Pt nanoparticles on carbon nanohorn aggregates by annular dark-field scanning confocal electron microscopy (ADF-SCEM) with an aberration-corrected microscope for three-dimensional (3D) imaging. The object elongation length along an optical axis that corresponds to the depth resolution was independent of the lateral size. Furthermore, the nanoparticle elongation length was reduced to 34 nm as compared with that by an uncorrected microscope. Hence, aberration-corrected ADF-SCEM provides structural information not only on the nanoparticles but also on the large carbon supports such as projecting nanohorns and hollow structures. Finally, aberration-corrected ADF-SCEM is effective for the 3D analysis of nanoparticle-supported composites.