Formation and electrochemical properties of multiwalled carbon nanotubes and polypyrrole composite with (n-Oc4N)Br binder

Abstract The electrochemical properties of a three-component composite containing polypyrrole, multiwalled carbon nanotubes and tetra(n-octyl)ammonium bromide as a binder have been investigated. The electrochemical behavior of this system depends on the relative amounts of the components within the composite. In the positive potential range, pseudo-capacitive behavior related to the polypyrrole oxidation is observed. The capacitance is enhanced due to the large surface area of the carbon nanotube substrate. Additionally, a contribution of double layer capacitance of multiwalled carbon nanotubes component leads to the capacitance increase. In consequence, high specific capacitance of approximately 600 F g−1 was obtained for this material. This value is about three times higher in comparison for the polymer deposited at the surface of bare gold electrode. The presence of tetra(n-octyl)ammonium bromide enhances the electrochemical and mechanical stability of the composite. The capacitance behavior of ternary composite is also more stable during cyclic charging/discharging processes in comparison to the polypyrrole film or polypyrrole/multiwalled carbon nanotube composite.