Modeling self-assembly of silica/surfactant mesostructures in the templated synthesis of nanoporous solids

Germán Pérez-Sánchez, Jose R. B. Gomes, Miguel Jorge

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

A novel coarse-grained (CG) model to study the self-assembly of silica/surfactant mesostructures during the synthesis of periodic mesoporous silica is reported. Molecular dynamics simulations of hexadecyltrimethylammonium bromide (also called cetyltrimethylammonium bromide, or CTAB) surfactants in water and in aqueous silicate solutions have been performed to understand micelle formation, micelle growth, and their size evolution during the synthesis of surfactant-templated mesoporous materials. Direct comparison of density profiles obtained for preassembled micelles employing an all-atom description, AA, with those calculated with the CG model has been carried out for checking the validity of the latter model. Good agreement between AA and CG approaches was found, demonstrating the potential of the CG approximation for modeling these highly complex systems. The micelle formation and micelle fusion/fission processes were analyzed after performing long CG simulations for surfactant and ionized silica–surfactant aqueous solutions. We observed the formation of rodlike micelles in the case of silica–surfactant solutions, while spherical micelles were stable under the same conditions for the CTAB+H2O system. This demonstrates that the interaction of anionic silicates with cationic surfactants promotes a sphere-to-rod transition in surfactant solutions, a key step in the synthesis of nanoporous silica materials.
LanguageEnglish
Pages2387–2396
Number of pages10
JournalLangmuir
Volume29
Issue number7
DOIs
Publication statusPublished - 19 Feb 2013

Fingerprint

Micelles
Surface-Active Agents
Silicon Dioxide
Self assembly
self assembly
Surface active agents
surfactants
Silica
micelles
silicon dioxide
synthesis
Silicates
bromides
silicates
Mesoporous materials
Cationic surfactants
complex systems
Molecular dynamics
Large scale systems
Fusion reactions

Keywords

  • silica/surfactant mesostructures
  • micelle formation
  • micelle growth
  • nanoporous silica material

Cite this

Pérez-Sánchez, Germán ; Gomes, Jose R. B. ; Jorge, Miguel. / Modeling self-assembly of silica/surfactant mesostructures in the templated synthesis of nanoporous solids. In: Langmuir. 2013 ; Vol. 29, No. 7. pp. 2387–2396.
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Modeling self-assembly of silica/surfactant mesostructures in the templated synthesis of nanoporous solids. / Pérez-Sánchez, Germán; Gomes, Jose R. B.; Jorge, Miguel.

In: Langmuir, Vol. 29, No. 7, 19.02.2013, p. 2387–2396.

Research output: Contribution to journalArticle

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