Effect of surfactants on PANI morphologies and supercapacitive properties

Abstract

Surfactant-mediated polyaniline (PANI) samples were fabricated using an electrodeposition technique for electrochemical supercapacitor applications. We investigated the effect of surfactants such as sodium dodecyl sulfate (SDS), polyvinyl alcohol (PVA), ethylenediaminetetraacetic acid (EDTA) on the PANI morphologies. The surfactants act as a template for PANI deposition during the electrodeposition, modifying the PANI morphology. Scanning electron microscope (SEM) images of the pure PANI samples showed a uniform nanocrystalline structure whilst the surfactant-mediated samples showed overgrown cauliflower-like structures. The electrochemical supercapacitive properties (charge-discharge) were studied in a 0.5 M LiClO4 electrolyte. While the capacitance of the pure PANI sample was 240 Fg−1 at a scan rate of 20 mVs−1, it was 199 Fg−1, 106 Fg−1, and 42 Fg−1 for the PANI-SDS, PANI-PVA and PANI-EDTA samples, respectively. The electrochemical stability of the samples was investigated for 1000 charge-discharge cycles by using cyclic voltammetry measurements.