Sinusoidal voltage electrodeposition and characterization of conducting polymers on gold microelectrode arrays

• Published in: Journal of electroanalytical chemistry (Lausanne, Switzerland) Switzerland), 2012-11, Vol.687, p.71-78
• Main Authors: Lupu, Stelian, del Campo, Francisco Javier, Muñoz, Francesc Xavier
• Format: Article
• Language: English
• Subjects: Conducting polymer; Electrochemical impedance spectroscopy; Microelectrode arrays; PEDOT; Sinusoidal voltages
• ISSN: 1572-6657; 1873-2569
• DOI: 10.1016/j.jelechem.2012.09.035

Cyclic voltammograms of soluble redox probe recorded at Au microelectrode arrays modified with poly(3,4-ethylenedioxythiophene) by sinusoidal voltages (SV-50mV) and potentiostatic procedure (CA). [Display omitted] ► We report electrodeposition of conducting polymers by using sinusoidal voltages. ► Conducting polymers were electrodeposited on gold microelectrode arrays. ► The electron transfer kinetics of redox probe at polymer surface was investigated. ► Amplitude of sinusoidal voltages influences the porosity of the polymers. ► The highest porosity was obtained at amplitude of 50mV. To the best of the authors’ knowledge, this is the first report on the electrochemical polymerization of 3,4-ethylenedioxythiophene on gold (Au) disk microelectrode arrays using sinusoidal voltages. The use of electrochemical impedance spectroscopy (EIS) for the in situ deposition of poly(3,4-ethylenedioxythiophene) (PEDOT) coating onto Au microelectrode arrays allowed the estimation of electrochemical parameters, such as charge transfer resistance and exchange current. The PEDOT coatings deposited on different arrays by sinusoidal voltages and potentiostatic methods were compared. The electrochemical characterization of both naked and PEDOT-modified microelectrode arrays by EIS and cyclic voltammetry (CV) revealed different diffusion regimes occurring at the microelectrodes surfaces. The electron transfer kinetics between the PEDOT coatings and redox probe in solution were also investigated. Results demonstrated the suitability of the new preparation procedure for electrogenerating PEDOT coatings. This novel procedure led to insights to the electrochemical properties and diffusion regimes occurring at both naked and modified microelectrode arrays.