Perspective and Prospects of In Situ Transmission/Scanning Transmission Electron Microscopy.

In situ transmission/scanning transmission electron microscopy (TEM/STEM) measurements have taken a central stage for establishing structure-chemistry-property relationship over the past couple of decades. The challenges for realizing 'a lab-in-gap', i.e., gap between the objective lens pole-pieces, or 'a lab-on-chip', to be used to carry out experiments are being met through continuous instrumental developments. Commercially available TEM columns and sample holder that have been modified for in situ experimentation have contributed to uncovering structural and chemical changes occurring in the sample when subjected external stimulus such as temperature, pressure, radiation (photon, ions, electrons), environment (gas, liquid, magnetic or electrical field), or a combination thereof. Whereas atomic resolution images and spectroscopy data are being collected routinely using TEM/STEM, temporal resolution is limited to millisecond. On the other hand, better than femto second temporal resolution can be achieved using an ultrafast electron microscopy (UEM) or dynamic electron transmission electron microscopy (DTEM), but the spatial resolution is limited to sub-nanometers. In either case, in situ experiments generate large datasets that need to be transferred, stored, and analyzed. The advent of artificial intelligence (AI), especially machine learning (ML) platforms are proving crucial to deal with this big data problem. Further developments are still needed in order to fully exploit our capability to understand, measure, and control chemical and/or physical processes. We present the current state of instrumental and computational capabilities and discuss future possibilities.

Informations de copyright

Published by Oxford University Press on behalf of The Japanese Society of Microscopy 2023. This work is written by (a) US Government employee(s) and is in the public domain in the US.