  Structural and compositional inhomogeneity is common in zeolites and
considerably affects their properties. Conventional transmission electron
microscopy (TEM) cannot provide sufficient information on local structures in
zeolites due to the thickness-limited lateral resolution, lack of depth
resolution, and electron dose-constrained focusing. We demonstrate that a
multislice ptychography method based on four-dimensional scanning TEM (4D-STEM)
data can overcome these limitations. The 4D-STEM ptychography image obtained
from a ~40-nm thick MFI zeolite exhibits an ultrahigh lateral resolution of
~0.85 {\AA}, enabling the unambiguous identification of individual framework
oxygen (O) atoms and the precise determination of the orientations of adsorbed
molecules. Furthermore, a depth resolution of ~6.6 nm is achieved, allowing the
three-dimensional probing of O vacancies and phase boundaries in zeolites. The
results of the 4D-STEM ptychography provide an unprecedented complete
understanding of the intergrowth of MFI and MEL zeolites in three dimensions.
The 4D-STEM ptychography can be generally applied to various zeolites and other
materials with similar electron beam sensitivity.
