Comparison of GO, GO/MWCNTs composite and MWCNTs as potential electrode materials for supercapacitors

Abstract

We report the synthesis of graphene oxide/multi-walled carbon nanotube (MWCNT) composites employing an alternative and novel approach for possible application as supercapacitor materials in energy storage devices. Integrating these nanostructures resulted in a strong synergistic effect between the two materials consequently leading to a robust and superior hybrid material with higher capacitance compared to either graphene oxide or MWCNTs. Specific capacitances of 251, 85 and 60 F g⁻¹ were obtained for graphene oxide-multi-walled carbon nanotubes, MWCNTs and graphene oxide, respectively, in a potential range from −0.1 to 0.5 V. Most importantly, a 120% increase in capacitance was observed with increasing cycle number at 20 mV s⁻¹. The ease of synthesis and the exceptional electrochemical properties make the use of this nanostructure an attractive, alternative way of designing future supercapacitors in both conventional fields and new emerging areas.