Electrochemical Behavior of Polyaniline-Poly(styrene sulfonate) Composite Films in Organic Electrolyte Solutions

Polyaniline-po]y(styrene sulfonate) (PAn-PSS) composite films have been synthesized by electropolymerization of aniline in aqueous med ia containing poly(styrene sulfonic acid). The electrochemical behavior of the film was studied in aqueous and organic electrolyte solutions using cyclic vo l tammetry and constant-current polarization techniques. In acidic aqueous solutions, the PAn-PSS composite film showed a reversible redox reaction accompan ied by cation transfer. The redox activity in organic electrolyte solutions depended on the composit ion of the solution measured. The composite film showed low redox activity during the initial cycles in 1 mol dm- ~ (M) L iC IQ solution of propylene carbonate (PC). The redox activity of the film increases significantly on repeated scans in a mixed solvent system (PC + 1,2-dimethoxyethane (DME)). Electron probe microanalysis experiments proved that the redox reaction of the composite film in organic elec-trolytes was accompan ied by a cation (Li +) transfer process between the film and the organic electrolyte. The coulombic efficiency of charge-discharge cycling under constant-current polarization was nearly 100 % after the redox activity reached a steady state. The electropolymerization of organic compounds such as pyrrole, thiophene, and aniline in solutions containing polyelectrolytes like poly(styrene sulfonate) (PSS) form