Group Members
Education-Graduate Student (MSc) at University of Alberta (2009-present).
-BSc in Applied Chemistry, Debub University, Ethiopia (2005).
Research Project:
Displacement of Thiol-Derived SAMs on Gold by Aryldiazonium Cations.
Project Description:
Surface modification with thiol-derived self-assembled monolayers (SAMs) is a popular way to alter the surface chemistry of substrates with specific functional groups. Also competitive and crucial in its specific advantages is modification with diazonium cation salt to form aryl-derived layers. The stabilities of both kinds of layers at different conditions are well investigated. This work therefore focuses on the study of the stability of thiol-derived SAMs on gold towards diazonium cation salts.
We use different spectroscopic, microscopic, and electrochemical techniques to track any changes in the structures of the SAMs upon spontaneous adsorption of aryldiazonium-derived layers. At specific points of displacement we are able to use Infrared Reflection Absorption Spectroscopy (IRRAS) to characterise changes in the structure of nitrobenzenethiol (tNB) SAM before and after treatment with diazonium of benzoic acid solution.
As well by monitoring the changes in open circuit potentials (OCP), supplemented with other techniques, of both the unmodified and tNB-modified gold substrates during spontaneous adsorption of dBA-derived layers we investigated the mechanism of the displacement process.
A general scheme for the mechanism and kinetics of the thiol-derived SAM displacement by aryldiazonium cation is underway by employing atomic force microscopy, supported with IRRAS and OCP measurements. The Kinetics of the displacement is mainly being investigated using displacement of different alkylthiol-derived SAMs by different aryldiazonium cations.