Polypyrrole-MoS2 Nanopetals as Efficient Anode Material for Lead-Based Hybrid Ultracapacitors

Abstract

Lead-carbon hybrid ultracapacitors are being a solution to the lead-acid battery to solve issues of sulfation and improve cycle life. In this work, we present polypyrrole-MoS2–based composite anode material coupled with PbO2 cathode for the lead-carbon hybrid ultracapacitors. Ultracapacitor behavior of polypyrrole-MoS2 based composite shows significant improvement in capacitance and power-density due to the synergetic effect of the high conducting polymer network and redox behavior of MoS2. The nanopetal shaped composite materials have been synthesized by a simple hydrothermal method at 160 oC by using polypyrrole. The composite Polypyrrole-MoS2 electrode delivers a specific capacitance of 782 Fg−1 at 1 A g−1 current density with low areal specificresistance (1.15 Ohm cm2) in an aqueous H2SO4 electrolyte. Besides, the PbO2/Polypyrrole-MoS2 hybrid ultracapacitors deliver capacitance of 285 F g−1 at 5 A g−1 and stable over 10,000 cycles. The improved capacitive behavior of the Polypyrrole-MoS2 composite electrode is due to the redox behavior, effective intercalation of H+ ions into the composite frameworks by transporting the electrons as well as have easy doping/de-doping of sulfate ions to the polypyrrole network.