Application of Films Consisting of Carbon Nanoparticles for Electrochemical Detection of Redox Systems in Organic Solvent Media

In the present article, the electrochemical sensitivity and response of films consisting of carbon nanoparticles were examined to test their potential applications as electrode materials for the construction of electrochemical sensors. For this purpose, a film of vertically aligned multi-walled carbon nanotubes (MWCNTs) on silicon dioxide substrate was synthesized by means of catalytic chemical vapor deposition (CVD) at 900oC using ferrocene (FeCp2) as catalyst and acetonitrile (ACN) as a carbon source. Furthermore, bucky-paper (BP) film was produced upon ultrasonic treatment of aqueous solution of single-walled carbon nanotubes (SWCNTs) in the presence of sodium dodecyl sulfate (SDS) micelle. In order to examine the electrochemical activity of the fabricated films, electrochemical studies of the oxidation of ferrocene (FeCp2) to ferrocenium cation (FeCp2 +) (where Cp denotes cyclopentadienyl anion) in ACN containing n-tetrabutylammonium hexafluorophosphat (NBu4PF6) as supporting electrolyte were performed. For the electrochemical experiments the techniques of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were employed. The electrochemical parameters of the FeCp2 +/0 redox couple in ACN on the fabricated films were determined and compared with those obtained using conventional glassy carbon (GC) electrode. The results demonstrate that the FeCp2 +/0 redox couple exposes Nernstian response on either MWCNT or GC electrodes while its response on BP film can be recognized as near Nernstian. The findings verify that the synthesized MWCNT and BP films hold promising and important applications in electro-analytical chemistry.