Electrochemical synthesis of pani/graphene nanocomposites aimed for sensors

This study is concerned with the electrochemical synthesis of polyaniline (PANI) based composites reinforced by carbon nanostructures (CNSs) such as graphene. To determine the optimal conditions for electropolymerization of the aniline to PANI, an electrochemical characterization was performed by means of cyclic voltammetry, steady state polarization and galvanostatic measurements. Within the CV spectra all steps of the transformation from aniline to polyaniline were observed with corresponding potential regions. It was found that the optimal potential for electropolymerization of the PANI based nanocomposites is 0.75 V vs. saturated calomel electrode (SCE). The electropolymerization rate was observed for two ways of involving of carbon nanostructures in the polymer matrix: dispersion in the electrolyte and previous deposition at the working electrode. The produced nanocomposites were characterized by means of Scanning Electron Microscopy (SEM) and Raman Spectroscopy. Strong interaction between the quinoidal structure of PANI and carbon nanostructures were detected. Electrical properties of the nanocomposite tablets were tested using the four probe method. These measurements show the great potential of the studied materials for sensors.