Synchronous quantitative analysis of chiral mesostructured inorganic crystals by 3D electron diffraction tomography

Abstract

Chiral mesostructures exhibit distinctive twisting and helical hierarchical stacking ranging from atomic to micrometre scales with fascinating structural-chiral anisotropy properties. However, the detailed determination of their multilevel chirality remains challenging due to the limited information from spectroscopy, diffraction techniques, scanning electron microscopy and the two-dimensional projections in transmission electron microscopy. Herein, we report a general approach to determine chiral hierarchical mesostructures based on three-dimensional electron diffraction tomography (3D EDT), by which the structure can be solved synchronously according to the quantitative measurement of diffraction spot deformations and their arrangement in reciprocal space. This method was verified on two samples—chiral mesostructured nickel molybdate and chiral mesostructured tin dioxide—revealing hierarchical chiral structures that cannot be determined by conventional techniques. This approach provides more precise and comprehensive identification of the hierarchical mesostructures, which is expected to advance our understanding of structural–chiral anisotropy at the fundamental level.

Chiral Plasmonic Hybrid Nanostructures: A Gateway to Advanced Chiroptical Materials

“…Consequently, the task of characterizing such intricate materials requires sophisticated techniques to uncover their structural evolution and chiral origin. Recent advances in characterization methods, such as TEM 3D tomography, aberration‐corrected STEM, [ 149 ] 3D electron diffraction tomography, [ 150 ] hold promise in offering a detailed view of chiral structures from atomic and nanoscales. In the case of complex asymmetric structures synthesized from the bottom‐up approach, their chiroptical properties can be obtained by conventional CD spectrometers.…”

Chirality Determination of Nanocrystals by Electron Crystallography

“…Ai et al reported a quantitative analysis method of chiral mesostructures by 3D ED with its application of five representative mesostructures in two typical chiral crystals (Figure 8). 68 Under ideal circumstances, single crystals have a 3D ED pattern with sharp diffraction spots, whereas those crystals with intrinsic bending, twisting, helical stacking, and other chiral hierarchical mesostructured forms would exhibit intricate diffraction patterns. The progressive changes and the correlation in the 3D reciprocal lattice were analyzed and calculated, including the arrangement of crystal lattices and rotational angles between atomic planes.…”

“…Figure 8. Schematic drawing of five representative crystal structures and their corresponding modulated diffraction spots in 3D reciprocal space (Copyright 2022, Springer Nature) 68. …”