Electrochemically controlled ion transport across polypyrrole/multi-walled carbon nanotube composite membranes

A1 Journal article (refereed)

Internal Authors/Editors

Publication Details

List of Authors: Marceline N. Akieh, Rose-Marie Latonen, Sten Lindholm, Stephen F. Ralph, Johan Bobacka, Ari Ivaska
Publisher: Elsevier
Publication year: 2011
Journal: Synthetic Metals
Volume number: 161
Issue number: 17-18
Start page: 1906
End page: 1914
eISSN: 1879-3290


Polypyrrole (PPy) films doped with acid-treated multi-walled carbon nanotubes (CNTs) were prepared by galvanostatic polymerisation of pyrrole (Py) dissolved in aqueous dispersions of CNTs, which served as the background electrolyte. Morphological characterization of PPy(CNT) films showed a random deposition of the polymer on the surface of the support material, with the former creating a porous, interconnecting three-dimensional network structure. The porous nature of PPy(CNT) films favours movement of large amounts of water in and out of the films during redox cycling, which also causes extensive volume changes. Raman spectroscopy, the electrochemical quartz crystal microbalance method and scanning electron microscopy were used to explore the properties of PPy(CNT) films. In addition, the factors influencing the electrochemically controlled transport of metal ions across composite membranes composed of polypyrrole doped with acid-treated multi-walled carbon nanotubes (PPy(CNT)) were studied. The factors examined were: The polymerization conditions (current density and time), the type of support material on which the polypyrrole films were deposited, and the use of single layer or bilayer type polypyrrole films. The flux of metal ions across the composite membranes was able to be electrochemically controlled when Nucleopore was controlled by the concentration gradient present when polyvinylidene difluoride (PVDF) was used as the support material for PPy(CNT) films. However, electrochemically controlled movement of metal ions across PVDF-supported membranes was achieved when a bilayer type PPy film (PPy(pTS)/PPy(CNT)) was used (pTS = toluene-4-sulfonic acid). Increasing the thickness of the PPy(CNT) layer in the composite membrane was found to enhance the membranes permeability towards K+.


bilayer polypyrrole film, electrically controlled ion transport, membrane, Multi-walled carbon nanotubes, polypyrrole

Last updated on 2020-02-04 at 07:35