Polypyrrole-MoS <sub>2</sub> Nanopetals as Efficient Anode Material for Lead-Based Hybrid Ultracapacitors
Sadananda Muduli, Vangapally Naresh, Subir K. Pati, Subrata Duary, Surendra K. Martha
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-MoS 2 –based composite anode material coupled with PbO 2 cathode for the lead-carbon hybrid ultracapacitors. Ultracapacitor behavior of polypyrrole-MoS 2 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 MoS 2 . The nanopetal shaped composite materials have been synthesized by a simple hydrothermal method at 160 o C by using polypyrrole. The composite Polypyrrole-MoS 2 electrode delivers a specific capacitance of 782 Fg −1 at 1 A g −1 current density with low areal specificresistance (1.15 Ohm cm 2 ) in an aqueous H 2 SO 4 electrolyte. Besides, the PbO 2 /Polypyrrole-MoS 2 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-MoS 2 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.