Surface-Enhanced Raman Spectroscopy Studies of Surfactant Adsorption to a Hydrophobic Interface
- 1 February 2008
- journal article
- research article
- Published by SAGE Publications in Applied Spectroscopy
- Vol. 62 (2), 149-156
- https://doi.org/10.1366/000370208783575492
Abstract
Surface-enhanced Raman spectroscopy is used to investigate the kinetics of adsorption of the cationic surfactant cetylpyridinium chloride (CPC) to hydrophobic surfaces from water. A hydrophobic surface, with stable and reproducible SERS activity, is produced by binding gold colloids to an amine-terminated glass slide and then modifying this surface with octadecyltrimethoxysilane. In situ SERS-detected adsorption of CPC from aqueous solution is found to follow a Frumkin isotherm. Interactions between the charged head groups could be detected in frequency shifts in the symmetric ring breathing mode, consistent with an interfacial surfactant environment similar to a CPC micelle. Rates of surfactant adsorption were determined by time-resolved SERS measurements and were found to be much slower than the diffusion-controlled limit, indicating a significant kinetic barrier to adsorption. Desorption kinetics were heterogeneous, consistent with the spectroscopic results. Alkylsilane-modified gold colloids were shown to be useful substrates for investigating amphiphile adsorption from aqueous solutions to hydrophobic surfaces, where the adsorption kinetics could also be used to determine analyte concentrations in solution.Keywords
This publication has 65 references indexed in Scilit:
- Competitive and displacement adsorption of cetylpyridinium chloride and p-nitrophenol on charged surfaces: A surface-enhanced Raman microprobe Scattering (SERS) studyPublished by Springer Science and Business Media LLC ,2007
- Three-Stage Multilayer Formation Kinetics during Adsorption of an Anionic Fluorinated Surfactant onto Germanium. 1. Concentration EffectThe Journal of Physical Chemistry B, 2005
- Quantitative SERS Measurements on Dielectric-Overcoated Silver-Island Films by Solution-Deposition Control of Surface ConcentrationsAnalytical Chemistry, 1999
- In-situ investigations of coadsorbed cationic surfactants on charged surfaces: a SERS microprobe studyColloids and Surfaces A: Physicochemical and Engineering Aspects, 1997
- Study of the Competitive Binding of TBA and CP Ions on C18SurfaceJournal of Liquid Chromatography & Related Technologies, 1996
- The change in structure of surfactant aggregates during adsorption/desorption processes and its effect on the stability of alumina suspensionColloids and Surfaces A: Physicochemical and Engineering Aspects, 1996
- Kinetics and Thermodynamics of Surfactant Adsorption at Model Interfaces: Evidence of Structural Transitions in the Adsorbed FilmsLangmuir, 1996
- Retention mechanisms in reversed-phase liquid chromatography. Stationary-phase bonding density and partitioningAnalytical Chemistry, 1989
- The molecular mechanism of retention in reversed-phase liquid chromatographyChemical Reviews, 1989
- Penetration-controlled reactions in organized monolayer assemblies. 2. Aqueous permanganate interaction with self-assembling monolayers of long-chain surfactantsLangmuir, 1987