Atomic-resolution imaging of gold species at organic liquid-solid interfaces

TL;DR

This study combines advanced microscopy, AI analysis, and innovative specimen design to achieve atomic-resolution imaging of gold species at organic liquid-solid interfaces, revealing dynamic behaviors relevant to catalysis.

Contribution

It introduces graphene liquid cells with organic solvents for in situ electron microscopy, enabling atomic-scale observation of gold adatoms and clusters in liquid environments.

Findings

Tracked over 10^6 gold adatoms and clusters at the interface.

Revealed dynamic correlated behaviors influenced by solvent and substrate.

Linked atomic behaviors to differences in catalytic activity.

Abstract

Understanding solid-liquid interfaces at the atomic-scale is key to improved performance of heterogeneous catalysts, electrodes and membranes. Here we combine unique specimen design, record atomic resolution in situ electron microscopy, and artificial intelligence-enabled analysis to achieve a step change in quantitative understanding of interfacial atomic behaviour. We create the first graphene liquid cells with organic solvents and employ them to track over 106 gold adatoms and clusters at a graphene surface immersed in acetone and cyclohexanone. We reveal dynamic correlated behaviour of gold adatom monomers, dimers, trimers and clusters, strongly influenced by each other, the solvent properties, and the atomic lattice of the substrate, in good agreement with theoretical calculations. We use the results to interpret differences in catalytic activity towards the industrially important acetylene hydrochlorination reaction. This new capability for exploration of atomic scale chemistry could enable rational design of future catalysts, membranes and electrodes with improved functionality.