SCIENCE

By

Hui Zhang, Guanxing Li, Jiaxing Zhang, Daliang Zhang, Zhen Chen, Xiaona Liu, Peng Guo, Yihan Zhu, Cailing Chen, Lingmei Liu, Xinwen Guo, and Yu Han

Published

11 May 2023

Abstract

Structural and compositional inhomogeneity is common in zeolites and considerably affects their properties. Thickness-limited lateral resolution, lack of depth resolution, and electron dose-constrained focusing limit local structural studies of zeolites in conventional transmission electron microscopy (TEM). We demonstrate that a multislice ptychography method based on four-dimensional scanning TEM (4D-STEM) data can overcome these limitations. Images obtained from a similar to 40-nanometer-thick MFI zeolite exhibited a lateral resolution of similar to 0.85 angstrom that enabled the identification of individual framework oxygen (O) atoms and the precise determination of the orientations of adsorbed molecules. Furthermore, a depth resolution of similar to 6.6 nanometers allowed probing of the three-dimensional distribution of O vacancies, as well as the phase boundaries in intergrown MFI and MEL zeolites. The 4D-STEM ptychography can be generally applied to other materials with similar high electron-beam sensitivity.

Full Text Link

https://www.science.org/doi/10.1126/science.adg3183