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The electrochemical growth of carbon nanotubes (CNTs) -conducting polymer composites offers the ability to produce three-dimensional nanostructured films that combine the redox pseudo-capacitive charge storage mechanism of conducting polymers with the high surface area and conductivity of CNTs [1 -3]. In this paper we report the electropolymerization and characterization of polypyrrole films (PPy) doped with poly (m-aminobenzenesulfonic acid) (PABS) functionalized single-walled carbon nanotubes (SWCNTs) (PPy/CNTs). The negatively charged CNTs served as anionic dopant during the electropolymerization to synthesize PPy/CNTs composite films. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and scanning electron microscopy (SEM) were used to investigate the electrochemical properties of the composite films.

The inhibition of zinc corrosion in 3.5% NaCl solution by some organic compounds (sodium dodecylsulphate (SDS), sodium dodecylbenzosulphonate (SDBS) and sodium 1,4-bis(2-etylhexyl) sulphosuccinate (AOT)) was investigated. The inhibition efficiencies were determined by polarization measurements of the zinc electrode in the solution. Electrochemical impedance spectroscopy (EIS) was also used for electrochemical studies of zinc electrode in this medium. The results showed that the used surfactants inhibit the cathodic reaction of hydrogen evolution and at low anodic overvoltage the corrosion process is under activation control, while at high anodic overvoltage the process is under diffusion control.

Copper nanowires enveloped in polyaniline (PANI) nanotubes were obtained by 'second order' electrodeposition into the pores of anodic porous alumina. The templated synthesis of copper nanowires was performed by both potentiostatic and galvanostatic methods. The morphology of the polyaniline nanotubes, copper nanowires as well as the copper-filled polyaniline nanotubes was investigated by means of scanning electron microscopy. The copper nanowires were protected from corrosion and oxidation by the PANI nanotubes. Energy-dispersive X-ray spectroscopy was performed for the microanalysis of the copper deposition into the polyaniline nanotubes. Cyclic voltammetry was employed to assess the electrochemical properties of the obtained nanostructures as well as the influence of the copper nanowires synthesis method on the properties of filled polyaniline nanotubes.

In this work, we combine two widely used techniques to produce modified electrodes, that is, the electroreduction of diazonium salts and the electropolymerization of conductive polymers in order to obtain polyaniline (PANI)/carbon nanotube (CNTs) composites. Thus, in a first step, a CNTs electrode was functionalized with 4-nitrophenyl group by electrochemical reduction of 4-nitrobenzenediazonium salt in nonaqueous media. Then, the nitro group was reduced electrochemically to amine functionality. Cyclic voltammetry and electrochemical impedance spectroscopy were used to trace the reactions in each step. The PANI film can easily be grafted onto the surface of such obtained aminophenyl-modified CNTs electrodes. The PANI/CNTs films generated by this strategy show electrochemical behavior similar to that of PANI simply electrodeposited on CNTs electrodes, but exhibit significantly improved stability and higher capacitance values.

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