Development of nanocomposites based on polypyrrole and carbon nanotubes for supercapacitors

Abstract

Supercapacitors are recognized as one of the most promising energy storage devices for a wide range of civilian and military applications in electric vehicles, uninterruptible power supplies. Conducting polymer nanocomposites are new functional materials suitable for supercapacitors due to synergistic effect of individual components. In present work, polypyrrole/CNT nanocomposites have been prepared by an in-situ chemical polymerization method and studied for supercapacitor. CNTs were well functionalized using 3:1 ratio of H2SO4 and HNO3 before polymerizing the pyrrole. Analytical techniques such as SEM, UV-VIS and FTIR were used to characterize the synthesized materials. The SEM images reveal that the materials have rough and granular morphology. The composites showed good interaction based on the shift to longer wavelengths in the electronic transition, indicating the interaction between PPy and functionalized CNTs as observed in their UV-VIS and FTIR spectra. The electrochemical performance was evaluated by using cyclic voltammetry (CV) in 1M Na2SO4 electrolyte and specific capacitance was obtained at 0.5 V/s for pure polypyrrole and PPy/CNT nanocomposites. Nanocomposite showed the enhanced electrochemical performance as compared to that of pure polypyrrole. The specific capacitance obtained at the scan rate 0.5V/s was found to be 0.825 F/cm-2 for pure polypyrrole and 1.0619 F/cm-2 for PPy/CNT nanocomposite material respectively, indicates that PPy/CNT nanocomposite is suitable material as electrode for supercapacitor as compoared to pure polypyrrole. Copyright. © 2014 VBRI press.