Influence of surfactant on the morphology and supercapacitive behavior of SILAR-deposited polyaniline thin films

Polyaniline thin films have been prepared by the simple and inexpensive successive ionic layer adsorption and reaction (SILAR) method at room temperature in the presence of three different surfactants (Triton X-100, polyethylene glycol, and sodium dodecyl sulfate) using ammonium peroxydisulfate (APS) as an oxidizing agent. The two-beaker SILAR system is adopted with aniline in 1 M H2SO4 solution as a cationic precursor and APS solution as an anionic precursor for polymerization of aniline. The polyaniline thin films are characterized by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), and cyclic voltammetry techniques. The properties of polyaniline thin films with surfactant are compared with those of surfactant-free polyaniline thin films. The polyaniline thin films prepared with surfactants exhibited different morphologies. The electrochemical characterizations of the supercapacitor based on polyaniline thin films are studied with cyclic voltammetry and charge-discharge techniques. The polyaniline thin film with Triton X-100 exhibited high specific capacitance (C (s)) of 1,040 F g(-1) and good cyclic stability (85 %) as compared to the C (s) of the surfactant-free polyaniline thin film (637 F g(-1)).