Study of Charge Compensation during the Redox Process of Self-Doped Polyaniline in Aqueous Media

One of the most important problems associated with use of polyaniline as a cathode material in rechargeable lithium batteries is related to energy density degradation due to the predomination of anion participation in the charge compensation process. This work describes the synthesis of a self-doped polyaniline, poly-(aniline-co-N-propanesulfonic acid-aniline), and evaluates its properties in aqueous acid solutions, with special attention to the increase of proton participation in the electroneutralization mechanism. The characterization was carried out using elemental analysis, FTIR and UV-vis spectroscopies. Electrochemical properties were investigated with the electrochemical quartz crystal microbalance and cyclic voltammetry. The results obtained show that proton participation was increased for the redox process of poly-(aniline-co- N-propanesulfonicacid-aniline) in relation to polyaniline.