Adsorption of sodium dodecyl sulfate on Ge substrate: the effect of a low-polarity solvent

Int J Mol Sci. 2012;13(7):7980-7993. doi: 10.3390/ijms13077980. Epub 2012 Jun 28.

Abstract

This paper describes the adsorption of sodium dodecyl sulfate (SDS) molecules in a low polar solvent on Ge substrate by using Fourier transform infrared-attenuated total reflection (FTIR-ATR) spectroscopy and atomic force microscopy (AFM). The maximum SDS amount adsorbed is (5.0 ± 0.3) × 10(14) molecules cm(-2) in CHCl(3), while with the use of CCl(4) as subphase the ability of SDS adsorbed is 48% lower. AFM images show that depositions are highly disordered over the interface, and it was possible to establish that the size of the SDS deposition is around 30-40 nm over the Ge surface. A complete description of the infrared spectroscopic bands for the head and tail groups in the SDS molecule is also provided.

Keywords: anionic surfactant; deposition; dichroism; vibrational spectra.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Chloroform / chemistry
  • Germanium / chemistry*
  • Microscopy, Atomic Force
  • Sodium Dodecyl Sulfate / chemistry*
  • Solvents / chemistry
  • Spectroscopy, Fourier Transform Infrared
  • Surface Properties
  • Surface-Active Agents / chemistry*

Substances

  • Solvents
  • Surface-Active Agents
  • Germanium
  • Sodium Dodecyl Sulfate
  • Chloroform