3D core-shell poly(aniline-co-pyrrole)/reduced graphene oxide composite for supercapacitor performance

Abstract

Due to favourable pseudo-capacitive performance, the polyaniline and polypyrrole are highly potential candidates for supercapacitor applications. In this study, core-shell poly(aniline-co-pyrrole) is prepared by in-situ chemical polymerization of pyrrole in the presence of polyaniline nanofibers. Poly(aniline-co-pyrrole) is mixed with the suspension of graphene oxide to prepare three-dimensional core-shell poly(aniline-co-pyrrole)/reduced graphene oxide composite using hydrothermal method. The as-synthesized samples are characterized by X-ray diffraction, Scanning electronic microscopy, Transmission electron microscope, FTIR spectroscopy, Raman spectroscopy and electrochemical measurements for the morphology, structure and supercapacitor performance of the composite. Results show that poly(aniline-co-pyrrole) is inlaid into the three-dimensional reduced graphene oxide. Poly(aniline-co-pyrrole)/reduced graphene oxide exhibits superior supercapacitor performance among the composites, benefiting from its unique composite structures, innate electrochemical properties and the synergistic effect of three-dimensional reduced graphene oxide and poly(aniline-co-pyrrole). The maximum specific capacitance of three-dimensional core-shell poly(aniline-co-pyrrole)/reduced graphene oxide composite prepared at a mass ratio of graphene oxide and poly(aniline-co-pyrrole) of 0.9:1 is 684.5 F·g−1 at a current density of 1 A·g−1. Even at a current density of 20 A·g−1, the specific capacitance still reaches 417 F·g−1. The capacitance retention of three-dimensional core-shell poly(aniline-co-pyrrole)/reduced graphene oxide electrode is 88% after 1000 charge and discharge cycles, showing excellent supercapacitor performance.