Effect of experimental factors on the properties of PEDOT-NaPSS galvanostatically deposited from an aqueous micellar media for invasive electrodes

Poly(3,4-ethylenedioxythiophene) (PEDOT) coat for invasive electrodes has been generated considerable interest in terms of electrical properties and biocompatibility. Adequate formulations and methodology are necessary to deposit polymer reproducibly on macro and micro-electrodes. Electrochemical properties of PEDOT as interface material were assessed with respect to different experimental factors. PEDOT/NaPSS was polymerized from a sodium polystyrenesulfonate (NaPSS) dispersion. The dispersion was characterized by cyclic voltammetry and its critical micellar concentration (CMC) value is reported, according to our best knowledge, for the first time for PEDOT deposition. The polymer obtained was studied using Raman spectroscopy, impedance and cyclic voltammetry measurement. PEDOT-NaPSS coat shows high charge injection (Q_inj), low interfacial impedance (Z) and superficial chemical stability (Raman). This study provides a simple, constant and reproducible framework to coat invasive electrodes.