Light sensitivity and potential stability of electrically conducting polymers commonly used in solid contact ion-selective electrodes

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Lindfors T
Publisher: SPRINGER
Publication year: 2009
Journal: Journal of Solid State Electrochemistry
Journal acronym: J SOLID STATE ELECTR
Volume number: 13
Issue number: 1
Start page: 77
End page: 89
Number of pages: 13
ISSN: 1432-8488


Abstract

The results of a systematic study of the light sensitivity and long-term potential stability (30 days) of poly(pyrrole) (PPy), poly(3-octylthiophene) (POT), poly(3,4-ethylenedioxythiophene) (PEDOT), poly(aniline) (PANI) and plasticised poly(vinyl chloride) (PVC) containing 20% (m/m) PANI are reported. Thin films were prepared either electrochemically or by the solution casting technique. This fundamental study is of importance because conducting polymers (CP) are commonly used as ion-to-electron transduction materials in all-solid-state solid contact ion-selective electrodes. The potential stability test done in 0.1 M KCl (pH 7.5) simulates the extreme situation when the CP-based SC becomes in direct contact with water. Films prepared of a nanodispersion of PANI showed both good potential stability and insensitivity to light even under illumination with very intensive light (> 10(5) lx). In contrary, it was observed that POT is very light-sensitive. Upon illumination with intensive light, the potential responses of POT films prepared by solution casting and electropolymerisation were 315 and 590 mV, respectively. A room light sensitivity of approximately -10 to -15 mV was observed for these films. The other CPs in this study were insensitive to room light (similar to 150 lx), but were light-sensitive under illumination with intensive light. The potential drift of PPy(Cl) is below -10 mu V/h (3-30 days), whereas the other most stable CPs in this study had a slightly higher potential drift.


Keywords

Conducting polymers, Ion-selective electrodes, Light sensitivity, Potential stability, Solid contact

Last updated on 2019-19-09 at 05:30