Imaging discrete ions at a liquid-solid interface using low-dose cryo-EM and electron counting

Instruments used

The K3^® IS camera delivers simultaneous low-dose imaging via real-time electron counting, fast continuous data capture, and a large field of view. The model 626 Liquid Nitrogen Cryo-Transfer Holder enables frost-free low-temperature specimen transfer and subsequent imaging of radiation-sensitive frozen samples at high resolution with precise temperature measurement.

Background

Cryo-electron microscopy (cryo-EM) imaging has revolutionized structural biology by enabling imaging of proteins and other biomolecules at near-atomic resolution. Now, the same low temperatures and electron dose rates are being applied to other aqueous materials. In this case, the liquid-solid interface between a positively charged gold nanorod and an aqueous solution of phosphotungstic acid was studied to provide insight into the individual and collective behavior of ions at that interface. Interactions between a solid surface, ions, and the solvent govern the behaviors of a wide variety of technologically relevant materials, including batteries, catalysts, colloids, membranes, and supercapacitors, so understanding those interactions is essential.