Potentiometric Ag+ Sensors Based on Conducting Polymers: A Comparison between Poly(3,4-ethylenedioxythiophene) and Polypyrrole Doped with Sulfonated Calixarenes

Abstract

Potentiometric Ag þ sensors were prepared by galvanostatic electropolymerization of 3,4-ethylenedioxythiophene (EDOT) and pyrrole (Py) on glassy carbon electrodes by using sulfonated calixarenes as doping ions. Poly(3,4-ethylenedioxythiophene) (PEDOT) and polypyrrole (PPy) doped with p-sulfonic calix[4]arene (C4S), p-sulfonic calix[6]arene (C6S) and p-sulfonic calix[8]arene (C8S) were compared. PEDOT and PPy doped with poly(styrene sulfonate) (PSS) were also included for comparison. The analytical performance of the conducting polymer-based Ag þ sensors was studied by potentiometric measurements. All conducting polymer and dopant combinations showed sensitivity and selectivity to Ag þ compared to several alkali, alkaline-earth, and transition-metal cations. The type of the conducting polymer used for the fabrication of the electrodes was found to have a more significant effect on the selectivity of the electrodes to Ag þ than the ring size of the sulfonated calixarenes used as dopants. Selected conducting polymer-based sensors were studied by cyclic voltammetry (CV) and energy dispersive analysis of X-rays (EDAX) measurements. Results from the EDAX measurements show that both PEDOT-and PPy-based membranes accumulate silver.

Correlation between ion-exchange properties and swelling/shrinking processes in hexasulfonated calix[6]arene doped polypyrrole films: ac-electrogravimetry and electrochemical atomic force microscopy investigations

“…One way to achieve this goal consists in using these ionic calixarenes as doping anions in electronically conducting polymer matrices (films or colloids) such as polypyrrole [20][21][22], poly-(ethylene-dioxy-thiophene) (PEDOT) [23] or polyaniline [24]. The elaboration of electrochemical sensors based on this strategy will succeed only on condition that the calixarene based dopants conserve the binding character and the selectivity they display in solution once they are incorporated in the polymer matrix, which was shown to be achieved for C6S doped polypyrrole films with a targeted analyte such as uranyle cations [22].…”

Ion‐Selective Organic Electrochemical Junction Transistors Based on Poly(3,4‐ethylenedioxythiophene) Doped with Poly(styrene sulfonate)

“…Our previous study showed that PEDOT: PSS-based potentiometric ion sensors are sensitive and selective to Ag þ in aqueous solutions [25]. For this reason, we decided to prepare Ag .…”

Electrochemical sensors of heavy metals using novel polymer-modified glassy carbon electrodes

“…Polymer-coated bismuth film electrodes for the determination of trace metals by sequential injection analysis/anodic stripping voltammetry were reported [25]. Bobacka and coworkers [26,27] reported the usage of several conducting polymers including poly(3-octylthiophene), poly(3,4-ethylenedioxythiophene) (PEDOT), and polypyrrole (PPy) with various dopants and showed that the type of the conducting polymer used for fabrication of the electrodes had a more significant effect on the sensitivity and selectivity of the electrodes towards the metal ions [28]. The polythiophene-modified glassy carbon electrode was used in the determination of metal ions such as Cu(II), Pb (II), Cd(II), and Zn(II) by differential pulse anodic stripping voltammetry [29].…”