From diffusive motion to local aggregation

Effect of surface contamination in dipolophoresis

Jae Sung Park, David Saintillan

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

We investigate the effects of surface contamination, modeled as a thin dielectric coating, on the dynamics in suspensions of ideally polarizable spheres in an applied electric field using large-scale direct particle simulations. In the case of clean particles (no contamination), the suspensions are known to undergo dipolophoresis, or a combination of dielectrophoresis, which tends to cause particle chaining and aggregation, and induced-charge electrophoresis, which dominates the dynamics and drives transient pairings, chaotic motions, and hydrodynamic diffusion at long times. As surface contamination becomes significant, induced-charge electrophoresis is gradually suppressed, which results in the simulations in a transition from diffusive dynamics to local aggregation and chaining as a result of dielectrophoresis. This effect has a strong impact on the suspension microstructure, as well as on particle velocities, which are strongly reduced for contaminated particles. This transition is also visible in the particle mean-square displacements, which become sub-diffusive in the case of strong contamination. We explain this sub-diffusive regime as a consequence of the slow dynamics of the particles trapped inside clusters and chains, which result in non-integrable local waiting time distributions.

Original languageEnglish (US)
Pages (from-to)10720-10727
Number of pages8
JournalSoft Matter
Volume7
Issue number22
DOIs
StatePublished - Nov 21 2011

Fingerprint

Electrophoresis
contamination
Contamination
Agglomeration
Suspensions
electrophoresis
Hydrodynamics
trapped particles
Electric fields
Coatings
Microstructure
simulation
hydrodynamics
coatings
microstructure
electric fields
causes

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics

Cite this

From diffusive motion to local aggregation : Effect of surface contamination in dipolophoresis. / Park, Jae Sung; Saintillan, David.

In: Soft Matter, Vol. 7, No. 22, 21.11.2011, p. 10720-10727.

Research output: Contribution to journalArticle

@article{2769a9ca5c6a4ade80ab3ad590449fe8,
title = "From diffusive motion to local aggregation: Effect of surface contamination in dipolophoresis",
abstract = "We investigate the effects of surface contamination, modeled as a thin dielectric coating, on the dynamics in suspensions of ideally polarizable spheres in an applied electric field using large-scale direct particle simulations. In the case of clean particles (no contamination), the suspensions are known to undergo dipolophoresis, or a combination of dielectrophoresis, which tends to cause particle chaining and aggregation, and induced-charge electrophoresis, which dominates the dynamics and drives transient pairings, chaotic motions, and hydrodynamic diffusion at long times. As surface contamination becomes significant, induced-charge electrophoresis is gradually suppressed, which results in the simulations in a transition from diffusive dynamics to local aggregation and chaining as a result of dielectrophoresis. This effect has a strong impact on the suspension microstructure, as well as on particle velocities, which are strongly reduced for contaminated particles. This transition is also visible in the particle mean-square displacements, which become sub-diffusive in the case of strong contamination. We explain this sub-diffusive regime as a consequence of the slow dynamics of the particles trapped inside clusters and chains, which result in non-integrable local waiting time distributions.",
author = "Park, {Jae Sung} and David Saintillan",
year = "2011",
month = "11",
day = "21",
doi = "10.1039/c1sm06172k",
language = "English (US)",
volume = "7",
pages = "10720--10727",
journal = "Soft Matter",
issn = "1744-683X",
publisher = "Royal Society of Chemistry",
number = "22",

}

TY - JOUR

T1 - From diffusive motion to local aggregation

T2 - Effect of surface contamination in dipolophoresis

AU - Park, Jae Sung

AU - Saintillan, David

PY - 2011/11/21

Y1 - 2011/11/21

N2 - We investigate the effects of surface contamination, modeled as a thin dielectric coating, on the dynamics in suspensions of ideally polarizable spheres in an applied electric field using large-scale direct particle simulations. In the case of clean particles (no contamination), the suspensions are known to undergo dipolophoresis, or a combination of dielectrophoresis, which tends to cause particle chaining and aggregation, and induced-charge electrophoresis, which dominates the dynamics and drives transient pairings, chaotic motions, and hydrodynamic diffusion at long times. As surface contamination becomes significant, induced-charge electrophoresis is gradually suppressed, which results in the simulations in a transition from diffusive dynamics to local aggregation and chaining as a result of dielectrophoresis. This effect has a strong impact on the suspension microstructure, as well as on particle velocities, which are strongly reduced for contaminated particles. This transition is also visible in the particle mean-square displacements, which become sub-diffusive in the case of strong contamination. We explain this sub-diffusive regime as a consequence of the slow dynamics of the particles trapped inside clusters and chains, which result in non-integrable local waiting time distributions.

AB - We investigate the effects of surface contamination, modeled as a thin dielectric coating, on the dynamics in suspensions of ideally polarizable spheres in an applied electric field using large-scale direct particle simulations. In the case of clean particles (no contamination), the suspensions are known to undergo dipolophoresis, or a combination of dielectrophoresis, which tends to cause particle chaining and aggregation, and induced-charge electrophoresis, which dominates the dynamics and drives transient pairings, chaotic motions, and hydrodynamic diffusion at long times. As surface contamination becomes significant, induced-charge electrophoresis is gradually suppressed, which results in the simulations in a transition from diffusive dynamics to local aggregation and chaining as a result of dielectrophoresis. This effect has a strong impact on the suspension microstructure, as well as on particle velocities, which are strongly reduced for contaminated particles. This transition is also visible in the particle mean-square displacements, which become sub-diffusive in the case of strong contamination. We explain this sub-diffusive regime as a consequence of the slow dynamics of the particles trapped inside clusters and chains, which result in non-integrable local waiting time distributions.

UR - http://www.scopus.com/inward/record.url?scp=84255183460&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84255183460&partnerID=8YFLogxK

U2 - 10.1039/c1sm06172k

DO - 10.1039/c1sm06172k

M3 - Article

VL - 7

SP - 10720

EP - 10727

JO - Soft Matter

JF - Soft Matter

SN - 1744-683X

IS - 22

ER -