Temperature dependent supercapacitive performance of NH3 modified TiO2 decorated PPy nanohybrids in various electrolyte systems

Abstract

Nanostructural porosity, temperature dominance and electrolytic behaviour are known to be the most effective parameters for enhancing the specific capacitance of the electrode material. Taking note of these features, nitrogen enriched TiO2/PPy nanohybrids have been successfully synthesized in the laboratory via chemical oxidative in-situ polymerization. The morphological and physicochemical characteristics were examined using FESEM, TEM, XRD, FTIR, Raman and XPS techniques. Impact of temperature and flow of NH3 through neat TiO2 contributed an additional enhancement in the capacitive properties in the form of nanocomposite. To investigate the medium at which electrical conduction become higher TiO2/PPy-4 nanohybrid (TiO2 calcined at 400 °C) was analyzed in different aqueous electrolyte (1 M Na2SO4, 1 M KCl and 1 M H2SO4). Among these 1 M H2SO4 yielding utmost gravimetric capacitance of 723 F g−1 at 1 A g−1 for TiO2/PPy-4 nanohybrid. In addition the fabricated asymmetric supercapacitive electrode material showed 64 W h kg−1 of energy density at 1 A g−1 with 2.7 Ω equivalent series resistance (ESR) and capacitance retention % (˜90%) after 2000 successive cycles indicating robust performance as an active electrode with long life span, electrochemical stability, high storage capacity and utilized as promising material in supercapacitor application.