  Zeolites have been used in industrial applications such as catalysts, ion
exchangers, and molecular sieves because of their unique porous atomic
structures. However, the direct observation of zeolitic local atomic structures
via electron microscopy is difficult owing to their low resistance to electron
irradiation. Subsequently, the fundamental relationships between these
structures and their properties remain unclear. A novel low-electron-dose
imaging technique, optimum bright-field scanning transmission electron
microscopy (OBF STEM) has recently been developed. It reconstructs images with
a high signal-to-noise ratio and a dose efficiency approximately two orders of
magnitude higher than that of conventional methods. Herein, we performed
low-dose atomic-resolution OBF STEM observations of an FAU-type zeolite,
effectively visualizing all the atomic sites in its framework. Additionally,
the complex local atomic structure of the twin boundaries in the zeolite was
directly characterized. The results of this study facilitate the
characterization of the local atomic structures in many electron-beam-sensitive
materials.
