Nickel foam based polypyrrole–Ag composite film: a new route toward stable electrodes for supercapacitors

Polypyrrole (PPy)–Ag composites have been directly deposited on a nickel foam via the redox reaction between pyrrole and silver nitrate. As a catalyst, the nickel foam was able to accelerate the redox reaction and lead to the formation of PPy–Ag composites, which shows a strong adhesive force to the substrate. The electrochemical properties of the PPy–Ag–nickel foam electrode were systematically investigated by using cyclic voltammetry, galvanostatic charge–discharge and cycle stability measurements in 0.5 M K2SO4 electrolyte. The redox performance properties, good charge–discharge stability and high specific capacitance of 493 F g−1 at a current density of 1 A g−1 demonstrated the appropriate application of the PPy–Ag–nickel foam electrode for the high energy density supercapacitors.