Visualizing Transient Ordering Phenomena in Dense Nanoparticle Clouds

Rieke von Seggern; Jasmin Pongratz; Christine Ziegler; Sascha Schäfer

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arXiv · 2606.11938

Visualizing Transient Ordering Phenomena in Dense Nanoparticle Clouds

Rieke von Seggern·Jasmin Pongratz·Christine Ziegler·Sascha Schäfer

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Abstract

The dynamics of nanoparticles within nanoscale liquid environments exhibit a range of complex phenomena driven by the interplay of processes at varying length scales. While these dynamics have profound technical implications, such as in nanoscale catalytic kinetics, ion-transport pathways in energy storage, and macromolecular crowding in biological systems, real-space imaging of dense, confined nanoparticle assemblies remains a significant challenge. Here, we present a liquid-phase transmission electron microscopy approach in which dense clouds of gold nanoparticles are formed within microfluidic channels, rendering the particle ensemble visible in bright-field electron imaging. This strategy enables direct imaging of different density-dependent particle ordering phenomena, including a local structuring of the colloidal liquid in nanoscale spaces, disordered dynamic clouds at high nanoparticle densities and the reversible formation of superlattice structures. Our results provide a unique window into the complex processes of colloidal self-organization at the nanoscale.

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Rieke von Seggern, Jasmin Pongratz, Christine Ziegler, Sascha Schäfer. 2026-06-10. Visualizing Transient Ordering Phenomena in Dense Nanoparticle Clouds. https://arxiv.org/abs/2606.11938

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