TITLE:
Electrochemical Impedance Spectroscopy for Investigation on Ion Permeation in Thioctic Acid Self-Assembled Monolayer
AUTHORS:
Fupeng Zhi, Qian Ma, Yanli Bai, Shiqing Qi
KEYWORDS:
Ion Permeation, Thioctic Acid, Self-Assembled Monolayer, Electrochemical Impedance Spectroscopy
JOURNAL NAME:
Journal of Surface Engineered Materials and Advanced Technology,
Vol.9 No.3,
July
26,
2019
ABSTRACT: Electrochemical
impedance spectroscopy was employed to investigate the permeation of
electrolyte ions in thioctic acid self-assembled monolayer when its structure
was changed by the interaction of copper ions. The ion permeation was
evaluated by using relatively low excitation frequencies, 0.2 Hz to 1000 Hz,
and quantified by an extra resistive component in the equivalent circuit (RSAM). The extent of ion permeation affected by the electrode potentials
and the electrolyte concentration were investigated. The experimental results
verified that RSAM decreased ~70% by interaction with copper ions and that RSAM increased ~2 - 3 times when the electrolyte concentration was decreased by 10 times.
This analysis can be performed without addition of redox species.