Scanning transmission electron microscopy of nanostructures

This article investigates nanostructures by means of scanning transmission electron microscopy. The electron microscope is uniquely suited to the study of individual nanostructures, allowing differentiation of different structures and properties that is difficult or impossible to do with techniques that provide a spatial average. The present generation of aberration correctors, which correct all aberrations up to third order, makes it possible to obtain sufficient sensitivity to image and spectroscopically analyze single atoms. This article begins with a brief overview of the correction of lens aberration in electron microscopy, followed by several examples of insights into nanomaterials and the atomic origins of their functionality. In particular, it considers semiconductor nanocrystals, semiconductor quantum wires, and nanocatalysts. It also discusses magnetism in gold and silver nanoclusters as well as charge ordering in manganites.