Mathematics

Research from Kyoto University has provided new information about science

  2008 SEP 15 - (VerticalNews.com) -- "Ultrafine monodisperse gold nanoparticles (AuNPs) were synthesized by an elegant sputtering of gold onto 1-n-butyl-3-methylimidazolium hexafluorophosphate (BMI-PF6) ionic liquid. It was found that the BMI-PF6 supramolecular aggregates were loosely coordinated to the gold nanoparticles and were replaceable with thiol molecules," scientists in Kyoto, Japan report.

  "The self-assembly of BMI-PF6-stabilized AuNPs onto a (3-mercaptopropyl)trimethoxysilane (MPS)-functionalized silicon surface in 2D arrays, followed by dodecanethiol (DDT) treatment, have been demonstrated using X-ray photoelectron spectroscopy, field emission scanning electron microscopy, and contact angle measurements. DDT treatment of tethered AuNPs revealed two types of interactions between AuNPs and the MPS -functionalized surface: (a) AuNPs anchor through Au-S chemisorption linkage resulting in strong immobilization and (b) some of the AuNPs are supported by physisorption, driven by BMI-PF6. The attachment of these particles remains unchanged with sonication. The replacement of BMI-PF6 aggregates from physisorbed AuNPs with DDT molecules advances the dilution of their interaction with the M PS -functionalized surface, and they subsequently detach from the silicon surface. The present finding is promising for the immobilization of ionic liquid-stabilized nanoparticles, which is very desirable for electronic and catalytic device fabrication," wrote O.P. Khatri and colleagues, Kyoto University.

  The researchers concluded: "Additionally, these environmentally friendly AuNPs are expected to replace conventional citrate-stabilized AuNPs."

  Khatri and colleagues published their study in Langmuir (Self-assembly of ionic liquid (BMI-PF6)-stabilized gold nanoparticles on a silicon surface: Chemical and structural aspects. Langmuir, 2008;24(15):7785-7792).

  For additional information, contact H. Sugimura, Kyoto University, Dept. of Materials Science & Engineering, Sakyo Ku, Kyoto 6068501, Japan.

  The publisher's contact information for the journal Langmuir is: American Chemical Society, 1155 16th St., NW, Washington, DC 20036, USA.

  Keywords: Conservation, Ecology, Emerging Technologies, Environment, Gold Nanoparticles, Nanoparticle, Nanotech, Nanotechnology, Supramolecular, Kyoto University.

  This article was prepared by VerticalNews Mathematics editors from staff and other reports. Copyright 2008, VerticalNews Mathematics via VerticalNews.com.