Electrosynthesis of Polyaniline on Carbon Fiber Felt: Influence of Voltammetric Cycles on Electroactivity

The carbon materials and conducting polymers are known by application in electronic devices. This work aims to study the initial steps parameters of polyaniline electrosynthesis on carbon felts annealed at 1600 K by changing the number of voltammetry cycles in aniline acid solution. The characterization was performed by Field Emission Gun – Scanning Electron Microscopy, X-ray Diffraction, Infrared Fourier Transform Spectroscopy, Raman Spectroscopy and Electrochemical Impedance Spectroscopy. Under increasing number of cycles, the growth was more intense and it was easy to observe the pores clogging. Besides, it was noticed that emeraldine formation occurred progressively, from structures less to more oxidized: the polyaniline less cycled resulted closest that leucoemeraldine; polyaniline from nine cycles resulted closest to emeraldine, but all of them showed electroactive defects related to electrical charge (polarons) and conductivity (bipolarons). It was also observed that prime layers of polyaniline, formed until three cycles, followed more intense attraction of charges in solution to layer surface. This effect was emphasized from 3rd to 6th cycles.