Polyaniline nanofibers–graphene oxide nanoplatelets composite thin film electrodes for electrochemical capacitors

Abstract

Composite thin films of polyaniline (PANI) nanofibers and graphene oxide (GO) nanoplatelets are synthesized through a simple electrodeposition process for electrochemical capacitors. The morphology and structure of the materials are investigated by field emission scanning electron microscopy, transmission electron microscopy, current sensing atomic force microscopy, X-ray photoelectron spectroscopy, Fourier transforms infrared spectroscopy, X-ray diffraction, and ultraviolet-visible spectroscopy. In the process of electrodeposition, the electrostatic interactions between the oxygen-functionalized graphene and aniline monomers at an electrolyte interface assisted the co-deposition of PANI nanofibers and GO nanoplatelets. These thin films have an excellent effect on the electrochemical properties with an electrochemical capacitance of 662 F g⁻¹ at a low current density of 0.025 mA cm⁻² with simultaneous high energy density (64.5 W h kg⁻¹) and high power density (1159 W kg⁻¹). The excellent electrochemical performance of the films is attributed to the unique structure of the material, showing synergy between PANI nanofibers and GO nanoplatelets.