Open gas-cell transmission electron microscopy at 0.5 Å information limit.

Area of Science:

• Materials Science
• Nanotechnology
• Physical Chemistry

Background:

• Transmission electron microscopy (TEM) achieves atomic resolution in vacuum, but in situ studies in reactive gases are limited.
• Visualizing nanomaterial behavior under gas exposure is crucial for understanding catalysis, corrosion, and crystal growth.

Purpose of the Study:

• To develop and demonstrate a TEM system with sub-Ångström resolution capable of operating at pressures up to 1 mbar.
• To enable in situ and operando imaging of nanomaterials in gaseous environments.

Main Methods:

• Utilized an open gas-cell with a four-stage differential pumping system.
• Incorporated a 5th order aberration corrector, monochromatized electron beam, and direct electron detection.
• Employed low electron dose-rate illumination and advanced imaging techniques like exit wave phase imaging.

Main Results:

• Achieved a 0.5 Å information limit at pressures up to 1 mbar using nanocrystalline gold in N2.
• Confirmed atomic resolution and observed potential location-dependent vibrational blur at surface terminations.
• Demonstrated the capability for high-resolution imaging of nanomaterials in gaseous conditions.

Conclusions:

• The developed TEM platform extends atomic resolution imaging to gas-phase nanomaterial studies.
• This advancement facilitates in situ and operando investigations of gas-surface interactions.
• Opens new avenues for research in catalysis, corrosion, and crystal growth.