Hierarchical structure of graphene oxide/polyaniline composite flexible supercapacitor

Abstract

Supercapacitors are popular due to their higher power density than that of batteries, and are widely used in power electronics. It bridges the gap between electrolytic capacitors and rechargeable batteries. Electrochemical pseudocapacitors use metal oxides or conducting polymers. The graphene oxide/polyaniline (GO/PANI) composite, as a supercapacitor electrode material was prepared to increase the energy storage efficiency of the supercapacitor. The graphene oxide was prepared by the modified Hummers method. The GO/PANI composite was prepared by In-situ polymerization of aniline in the presence of Graphene oxide. The performance of the electrode is evaluated using aqueous electrolyte at various current densities and scan rate. The electrochemical property and impedance of the composites are characterized by CV, GCD and EIS. From the GCD analysis, GO exhibited the highest specific capacitance of 255 F g−1 at the current density 10 A g−1. Similarly, the composite showed the highest specific capacitance of 327 F g−1 at the current density 10 A g−1. Compared to GO, the GO/PANI composite exhibited an excellent capacitance of 327 Fg−1 in 6 M KOH electrolyte. Rs and Rct of GO/PANI composite electrode were calculated as 23 Ω and 28 Ω respectively. From the synergistic effects between GO and PANI, high electrochemical performance was attributed. Thus, the results show that the introduction of the GO and PANI, enhanced the electrode conductivity and stability, and then improved the supercapacitive behaviour of GO/PANI. These fascinating characteristics make GO/PANI composite as a promising candidate in supercapacitors.