Electro-deposited halloysite nanotube/polyaniline nanocomposites for energy storage applications

Abstract

A nanocomposite (nanoclay/conductive polymer) was prepared by a template-free method for supercapacitor applications. Halloysite Nanotubes (HNTs) were used as a nanoclay material, and synthesized polyaniline (PANI) by ammonium persulfate-initiated polymerization was used as a conductive polymer. The HNTs/PANI nanocomposite was deposited on an indium tin oxide (ITO) coated glass to obtain a working electrode by an electrochemical deposition method. Morphological and structural examination of the HNTs/PANI nanocomposite proved that the PANI nanoparticles were attached to the HNTs surface. The structural analysis demonstrated that the PANI and HNTs crystal size significantly decreased in the HNTs/PANI as a result of the composition of PANI molecules with HNTs structure. The main characteristic bonds and functional groups of HNT, PANI, and HNTs/PANI nanocomposites were determined by FT-IR analysis. Using cyclic voltammetry (CV), the electrochemical performance of the HNTs//PANI nanocomposite electrode was investigated. The specific capacitance values were reported via the CV curves as 264, 230.22, 175.2, and 154.8 F/g at scan rates of 50, 100, 200, and 300 mV/s respectively. The results showed that the specific capacitance at the slow scan rates revealed higher maximum specific capacitance values.