One-Pot Hydrothermal Synthesis of Reduced Graphene Oxide–Multiwalled Carbon Nanotubes Composite Material on Nickel Foam for Efficient Supercapacitor Electrode

Abstract

The reduced graphene oxide/multiwalled carbon nanotubes deposited on nickel foam (rGO/MWCNTs/NF) composite material was successfully prepared using one-pot hydrothermal method. The prepared rGO/MWCNTs/NF composite material was characterized using scanning electron microscopy, electron dispersive spectroscopy, and Raman spectroscopy. The results show that MWCNTs were successfully incorporated into the graphene sheets uniformly. The rGO/MWCNTs/NF composite material was fabricated as electrode for supercapacitor application. The capacitive properties of the rGO/MWCNTs/NF composite material were studied using electrochemical impedance spectroscopy, cyclic voltammetry, and galvanostatic charge/discharge in 1 M KOH aqueous electrolyte solution. The rGO/MWCNTs/NF electrode showed enhanced capacitance compared to rGO/NF, MWCNTs/NF, and bare NF electrodes due to high surface area and more accessibility of electrolyte after the addition of MWCNTs to the rGO/NF electrode. The rGO/MWCNTs/NF composite material shows specific capacitance of 81.14 F g−1 at current density of 1 A g−1 and excellent cycling stability with 83 % of its initial capacitance after 1000 charge/discharge cycles.