Solution-cast films of poly(3,4-ethylenedioxythiophene) as ion-to-electron transducers in all-solid-state ion-selective electrodes

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Vazquez M, Danielsson P, Bobacka J, Lewenstam A, Ivaska A
Publisher: ELSEVIER SCIENCE SA
Publication year: 2004
Journal: Sensors and Actuators B: Chemical
Journal acronym: SENSOR ACTUAT B-CHEM
Volume number: 97
Issue number: 2-3
Start page: 182
End page: 189
Number of pages: 8
ISSN: 0925-4005


Abstract

An aqueous dispersion of poly(3,4-ethylenedioxythiophene) (PEDOT) doped with poly(styrenesulfonate) (PSS) was cast on screenprinted gold substrates. PEDOT(PSS) was ionically (physically) crosslinked by multivalent cations, including Mg2+, Ca2+, Fe2+/3+ and Ru(NH3)(6)(2+/3+) to form a hydrogel in order to decrease the water solubility of the PEDOT(PSS). The resulting Au/PEDOT(PSS) electrodes were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and energy-dispersive X-ray analysis (EDXA). Ionic crosslinking of PEDOT(PSS) with Fe2+/3+ and Ru(NH3)(6)(2+/3+) was faster than with Mg2+ and Ca2+ ions and resulted in PEDOT(PSS) films that were less soluble in water. Among the multivalent cations tested, Ru(NH3)(6)(2+/3+) resulted in PEDOT(PSS) films with the most stable potential. Incorporation of Ru into PEDOT(PSS) was shown by EDXA. Based on CV and EIS, ionic crosslinking of PEDOT(PSS) with the electroactive Ru(NH3)(6)(2+/3+) was found to increase the bulk redox capacitance of the PEDOT(PSS) film, compared to ionic crosslinking with electroinactive Mg2+ ions. Potentiometric measurements showed that PEDOT(PSS) ionically crosslinked with Ru(NH3)(6)(2+/3+) was less sensitive to CO2 (pH) than the bare An substrate. The Au/PEDOT(PSS) electrodes were found to work well as ion-to-electron transducer (solid contact) in all-solid-state K+-ion- selective electrodes (ISEs). (C) 2003 Elsevier B.V. All rights reserved.


Keywords

All-solid-state ion-selective electrode, ionic crosslinking, Ion-to-electron transducer

Last updated on 2020-25-02 at 05:07