A novel method of preparing metallic Janus silica particles using supercritical carbon dioxide

Qiuyan Yang, Marcel H de Vries, Francesco Picchioni, Katja Loos*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

24 Citations (Scopus)

Abstract

In this study, we demonstrate a novel fabrication method to prepare metallic Janus silica particles by embedding nanosized silica particles on a spherical polystyrene (PS) substrate in supercritical carbon dioxide (sc CO2), followed by labelling with gold nanoparticles on the exposed part of the silica colloids. To this end, three main types of Janus particles displaying two distinct surfaces are produced by recovering silica from the polystyrene template. Embedment of particles into the PS template in sc CO2 allows for precise control of the degree of embedding of particles and subsequent modification of the partially exposed particle surface. The embedding degree, as well as the final Janus balance, can be varied over a wide range through control of pressure, temperature, or treatment time of sc CO2. Hierarchical PS-silica composites and embedment are evaluated by scanning electron microscopy (SEM). Partial surface modification with gold nanoparticles is investigated by transmission electron microscopy (TEM). With this method various functionalized Janus particles with tuneable properties can be prepared by adjusting various surface modifiers and polymer substrates in the future.

Original languageEnglish
Pages (from-to)10420-10427
Number of pages8
JournalNanoscale
Volume5
Issue number21
DOIs
Publication statusPublished - 7-Nov-2013

Keywords

  • MODULATED OPTICAL NANOPROBES
  • GOLD NANOPARTICLES
  • POLYMER BLENDS
  • CO2
  • POLYSTYRENE
  • FABRICATION
  • INTERFACE
  • FUNCTIONALIZATION
  • TEMPERATURE
  • PATCHINESS

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