Chemical synthesis of PANI–TiO2 composite thin film for supercapacitor application

Abstract

A unique and cost effective chemical route has been carried out for the synthesis of a polyaniline–titanium oxide (PANI–TiO₂) composite thin film at room temperature. Characterization techniques, such as Fourier transform infrared and FT-Raman spectroscopy; have shown the formation of the composite. The result of X-ray diffraction indicates the amorphous nature of the PANI–TiO₂ composite thin film. The morphology of the PANI–TiO₂ composite thin film observed using scanning electron microscopy shows the porous framework of the agglomerated nanofibers. The electrochemical characterization of the pseudocapacitive PANI–TiO₂ composite in a 1 M H₂SO₄ electrolyte displayed the highest specific capacitance of 783 F g⁻¹ at the scan rate of 5 mV s⁻¹. The synergistic effect between PANI with its counterpart TiO₂ caused an increased cycle stability of 78% over 5000 consecutive cycles, which is higher than the virgin PANI with 70% specific capacitance retention. The distinctive structure of the PANI–TiO₂ composite and the cohabitation of conducting PANI with TiO₂ have been found to be responsible for the superior electrochemical properties.