Micro-Capacitor Behavior of Poly(3-Hexyl Thiophene)/Carbon Fiber/Electrolyte System and Equivalent Circuit Model

Abstract

In this article, 3-Hexyl thiophene (3HTh) monomer was electrocoated on carbon fiber micro electrode (CFME) to study electrochemical impedance spectroscopic (EIS) analysis. Poly(3HTh)/CFME is characterized by Cyclic voltammetry (CV), Fourier transform infrared reflectance-attenuated total reflection spectroscopy (FTIR-ATR), Scanning electron microscopy-Energy Dispersive X-ray analysis (SEM-EDX), and electrochemical impedance spectroscopy (EIS). The effects of different monomer concentrations (0.5, 1.0 and 1.5 mM) on polymer were reported in 0.1 M tetraethyl ammonium tetrafluoroborate (TEABF₄)/acetonitrile (ACN) solution. The highest low frequency capacitance (C_LF = 1.394 mF cm⁻²) was obtained for [3HTh]₀ = 0.5 mM. The equivalent circuit model of R(QR(CR)(RW))(CR) was examined for polymer/electrolyte system.

Keywords:

• 3-Hexylthiophene
• Carbon fiber
• Circuit model
• Coatings
• Micro-capacitor
• Thin films

ACKNOWLEDGMENTS

This work was supported by the Research Foundation of Namik Kemal University (Project No. (NKU.BAP.00.10.AR.11.01). The authors thank Ozlem Oskan (Afyon Kocatepe University, Technology and Research Center (TUAM), Afyon, Turkey) for recording the SEM-EDX point analysis. The authors also thank to Prof. Dr. A. Sezai Sarac for the usage of the Electropol Laboratory at Istanbul Technical University, Istanbul, Turkey.

Notes

Monomers deposited electrochemically at a scan rate of 100 mV s⁻¹, using multiple (8 cycle) in 0.1 M TEABF₄/ACN.