A Comparative Study of Redox Parameters and Electrochemical Impedance Spectroscopy of Polycarbazole Derivatives on Carbon Fiber Microelectrode

Abstract

In this study, N-Carbazole and its derivatives (N-Vinylcarbazole, N-Ethylcarbazole, N-Vinylbenzylcarbazole, and N-Benzylcarbazole) were electrochemically polymerized on carbon fiber microelectrodes (diameter similar to 7 mu m) by cyclic voltammetry within a potential range from 0.0 to 1.4 V. Redox parameters, Scanning electron microscopic (SEM) images were determined and also capacitance behaviors of polymers were examined via electrochemical impedance spectroscopy (EIS). EIS measurements of polycarbazole derivatives were given comparatively. The existence of a capacitance behavior is shown by Nyquist, Bode magnitude, Bode-phase, Admittance plots relationship. Although the highest low frequency capacitance (C-LF=12901 mu A cm(-2)) and maximum phase angle of 81.9 degrees at a frequency of 1 Hz were obtained for N-Vinylbenzylcarbazole, the lowest anodic and cathodic potential difference (Delta E=0.04 V) and double layer capacitance (C-dl=0.11 mu A cm(-2)) were indicated in 0.1 M LiClO4/PC.