Synthesis of nitrogen-doped reduced graphene oxide-multiwalled carbon nanotube composite on nickel foam as electrode for high-performance supercapacitor

An electrode with nitrogen-doped reduced graphene oxide/multiwall carbon nanotubes deposited on nickel foam (N-rGO/MWCNTs/NF) was successfully prepared using a simple one-pot hydrothermal method. The N-rGO/MWCNTs/NF composite was fabricated as an electrode for supercapacitor application. The super capacitive performance of the N-rGO/MWCNTs/NF electrode was studied using electrochemical impedance spectroscopy, cyclic voltammetry, and galvanostatic charge/discharge in a 6 M KOH electrolyte solution. The N-rGO/MWCNTs/NF electrode showed an enhanced capacitance compared to rGO/MWCNTs/NF, N-rGO/NF, N-MWCNTs/NF, and bare NF electrodes because of nitrogen atom doping and more accessibility of the electrolyte after the incorporation of MWCNTs between the graphene sheets. The N-rGO/MWCNTs/NF electrode showed a specific capacitance of 142.08 F g(-1) at a current density of 1 A g(-1) and cycling stability with 76.2% of its initial capacitance after 1000 charge/discharge cycles.