Comparison of morphology and mechanical properties of surfactant aggregates at water-silica and water-graphite interfaces from molecular dynamics simulations

Kunal Shah, Patrick Chiu, Susan B. Sinnott

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

Cationic surfactants are important for a wide range of applications, including controlled drug delivery systems, emulsifiers, and chemical mechanical polishing. It is therefore important to better understand surfactant structure and properties at the solid-liquid interface. Here, classical molecular dynamics simulations with empirical potentials are used to compare the structures and mechanical properties of cationic surfactant micelles at hydrophobic (graphite) and hydrophilic (silica) surface-water interfaces. In particular, the morphology of monolayers and bilayers of C12TAB (n- dodecyltrimethylammoniumbromide) at these interfaces, and their responses to atomic force microscopy indentation, are examined. The simulations predict that surfactant monolayers and bilayers on silica evolve into a spherical micelle structure, in agreement with theoretical models of surfactant morphology. In contrast, surfactant monolayers on graphite evolve into a hemi-cylindrical structure, in agreement with experimental findings. In the simulated indentation of the micelle/silica system, the spherical micelle breaks apart and forms a surfactant monolayer. The indentation force curve has a maximum value of 2.25 nN. On the other hand, the simulated indentation of the micelle/graphite system causes the hemi-cylindrical micelle structure to break apart and the surfactant tails to wrap around the graphite indenter. The indentation force curve has a maximum value of 13 nN.

Original languageEnglish (US)
Pages (from-to)342-349
Number of pages8
JournalJournal of Colloid And Interface Science
Volume296
Issue number1
DOIs
StatePublished - Apr 1 2006

Fingerprint

Graphite
Micelles
Surface-Active Agents
Silicon Dioxide
Interfaces (computer)
Molecular dynamics
Indentation
Surface active agents
Silica
Mechanical properties
Water
Monolayers
Computer simulation
Cationic surfactants
Controlled drug delivery
Chemical mechanical polishing
Surface waters
Atomic force microscopy
Liquids

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Surfaces, Coatings and Films
  • Colloid and Surface Chemistry

Cite this

@article{57a221247e3a4fb4bed9f8bf1259142f,
title = "Comparison of morphology and mechanical properties of surfactant aggregates at water-silica and water-graphite interfaces from molecular dynamics simulations",
abstract = "Cationic surfactants are important for a wide range of applications, including controlled drug delivery systems, emulsifiers, and chemical mechanical polishing. It is therefore important to better understand surfactant structure and properties at the solid-liquid interface. Here, classical molecular dynamics simulations with empirical potentials are used to compare the structures and mechanical properties of cationic surfactant micelles at hydrophobic (graphite) and hydrophilic (silica) surface-water interfaces. In particular, the morphology of monolayers and bilayers of C12TAB (n- dodecyltrimethylammoniumbromide) at these interfaces, and their responses to atomic force microscopy indentation, are examined. The simulations predict that surfactant monolayers and bilayers on silica evolve into a spherical micelle structure, in agreement with theoretical models of surfactant morphology. In contrast, surfactant monolayers on graphite evolve into a hemi-cylindrical structure, in agreement with experimental findings. In the simulated indentation of the micelle/silica system, the spherical micelle breaks apart and forms a surfactant monolayer. The indentation force curve has a maximum value of 2.25 nN. On the other hand, the simulated indentation of the micelle/graphite system causes the hemi-cylindrical micelle structure to break apart and the surfactant tails to wrap around the graphite indenter. The indentation force curve has a maximum value of 13 nN.",
author = "Kunal Shah and Patrick Chiu and Sinnott, {Susan B.}",
year = "2006",
month = "4",
day = "1",
doi = "10.1016/j.jcis.2005.08.060",
language = "English (US)",
volume = "296",
pages = "342--349",
journal = "Journal of Colloid and Interface Science",
issn = "0021-9797",
publisher = "Academic Press Inc.",
number = "1",

}

TY - JOUR

T1 - Comparison of morphology and mechanical properties of surfactant aggregates at water-silica and water-graphite interfaces from molecular dynamics simulations

AU - Shah, Kunal

AU - Chiu, Patrick

AU - Sinnott, Susan B.

PY - 2006/4/1

Y1 - 2006/4/1

N2 - Cationic surfactants are important for a wide range of applications, including controlled drug delivery systems, emulsifiers, and chemical mechanical polishing. It is therefore important to better understand surfactant structure and properties at the solid-liquid interface. Here, classical molecular dynamics simulations with empirical potentials are used to compare the structures and mechanical properties of cationic surfactant micelles at hydrophobic (graphite) and hydrophilic (silica) surface-water interfaces. In particular, the morphology of monolayers and bilayers of C12TAB (n- dodecyltrimethylammoniumbromide) at these interfaces, and their responses to atomic force microscopy indentation, are examined. The simulations predict that surfactant monolayers and bilayers on silica evolve into a spherical micelle structure, in agreement with theoretical models of surfactant morphology. In contrast, surfactant monolayers on graphite evolve into a hemi-cylindrical structure, in agreement with experimental findings. In the simulated indentation of the micelle/silica system, the spherical micelle breaks apart and forms a surfactant monolayer. The indentation force curve has a maximum value of 2.25 nN. On the other hand, the simulated indentation of the micelle/graphite system causes the hemi-cylindrical micelle structure to break apart and the surfactant tails to wrap around the graphite indenter. The indentation force curve has a maximum value of 13 nN.

AB - Cationic surfactants are important for a wide range of applications, including controlled drug delivery systems, emulsifiers, and chemical mechanical polishing. It is therefore important to better understand surfactant structure and properties at the solid-liquid interface. Here, classical molecular dynamics simulations with empirical potentials are used to compare the structures and mechanical properties of cationic surfactant micelles at hydrophobic (graphite) and hydrophilic (silica) surface-water interfaces. In particular, the morphology of monolayers and bilayers of C12TAB (n- dodecyltrimethylammoniumbromide) at these interfaces, and their responses to atomic force microscopy indentation, are examined. The simulations predict that surfactant monolayers and bilayers on silica evolve into a spherical micelle structure, in agreement with theoretical models of surfactant morphology. In contrast, surfactant monolayers on graphite evolve into a hemi-cylindrical structure, in agreement with experimental findings. In the simulated indentation of the micelle/silica system, the spherical micelle breaks apart and forms a surfactant monolayer. The indentation force curve has a maximum value of 2.25 nN. On the other hand, the simulated indentation of the micelle/graphite system causes the hemi-cylindrical micelle structure to break apart and the surfactant tails to wrap around the graphite indenter. The indentation force curve has a maximum value of 13 nN.

UR - http://www.scopus.com/inward/record.url?scp=33644599154&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33644599154&partnerID=8YFLogxK

U2 - 10.1016/j.jcis.2005.08.060

DO - 10.1016/j.jcis.2005.08.060

M3 - Article

C2 - 16183072

AN - SCOPUS:33644599154

VL - 296

SP - 342

EP - 349

JO - Journal of Colloid and Interface Science

JF - Journal of Colloid and Interface Science

SN - 0021-9797

IS - 1

ER -