Atomic Resolution Cryogenic 4D-STEM Imaging via Robust Distortion Correction

Abstract

Cryogenic four-dimensional scanning transmission electron microscopy (4D-STEM) imaging is a useful technique for studying quantum materials and their interfaces by simultaneously probing charge, lattice, spin, and chemistry on the atomic scale with the sample held at temperatures ranging from room to cryogenic. However, its applications are currently limited by the instabilities of cryo-stages and electronics. To overcome this challenge, we develop an algorithm to effectively correct the complex distortions present in atomic resolution cryogenic 4D-STEM data sets. This method uses nonrigid registration to identify localized distortions in a 4D-STEM and relate them to an undistorted experimental STEM image, followed by a series of affine transformations for distortion corrections. This method allows a minimum loss of information in both reciprocal and real spaces, enabling the reconstruction of sample information from 4D-STEM data sets. This method is computationally cheap, fast, and applicable for on-the-fly data analysis in future in situ cryogenic 4D-STEM experiments.

C60 and Derivatives Boost Electrocatalysis and Photocatalysis: Electron Buffers to Heterojunctions

“…A spherical aberration‐corrected electron microscope, when properly equipped, can provide valuable insights into the interfacial charge distribution of heterojunctions in catalytic materials. [ 81–84 ] The introduction of C 60 and derivatives into a core‐shell system results in the liberation of electrons held within the system. This phenomenon demonstrates the catalytic potential of core–shell structures in facilitating reduction processes.…”