Polyaniline/carbon nanotube composite films electrosynthesis through diazonium salts electroreduction and electrochemical polymerization

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.