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arXiv · 2112.00243

Electric Field Induced Macroscopic Cellular Phase of Nanoparticles

Abigail Rendos·Wenhan Cao·Margaret Chern·Marco Lauricella·Sauro Succi·Joerg G. Werner·Allison M. Dennis·Keith A. Brown
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Abstract

A suspension of nanoparticles with very low volume fraction is found to assemble into a macroscopic cellular phase under the collective influence of AC and DC voltages. Systematic study of this phase transition shows that it was the result of electrophoretic assembly into a two-dimensional configuration followed by spinodal decomposition into particle-rich walls and particle-poor cells mediated principally by electrohydrodynamic flow. This mechanistic understanding reveals two characteristics needed for a cellular phase to form, namely 1) a system that is considered two dimensional and 2) short-range attractive, long-range repulsive interparticle interactions. In addition to determining the mechanism underpinning the formation of the cellular phase, this work presents a method to reversibly assemble microscale continuous structures out of nanoscale particles in a manner that may enable the creation of materials that impact diverse fields including energy storage and filtration.

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Abigail Rendos, Wenhan Cao, Margaret Chern, Marco Lauricella, Sauro Succi, Joerg G. Werner, Allison M. Dennis, Keith A. Brown. 2021-12-01. Electric Field Induced Macroscopic Cellular Phase of Nanoparticles. https://arxiv.org/abs/2112.00243

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