Spotlighting the boosted energy storage capacity of Cofe2O4/graphene nanoribbons: A promising positive electrode material for high-energy-density asymmetric supercapacitor

Abstract

CoFe2O4/Graphene Nanoribbons (GNRs) nanocomposite was successfully fabricated and utilised as an electrode active material for high-energy supercapacitor cells. Thanks to the outstanding physicochemical features of a graphene nanoribbon with excellent electrical conductivity and the synergistic effect with cobalt ferrite, as well as the pseudocapacitive effect. The CoFe2O4/GNRs nanohybrid offered an exceptional specific capacitance of 922 F g-1 (415 C g-1) at 1.0 A g-1 in 3.0 M KOH electrolyte in a standard 3-electrode set-up. Additionally, the impressive supercapacitive performance metrics showed that the suggested electrode had a distinctive morphology and could be a candidate for capacitive energy storage systems. These metrics included good cycle stability and 87% capacitance retention at the end of the 10,000th CV cycle. Moreover, the asymmetric supercapacitor cell (ASC) was designed by assembling CoFe2O4/GNRs and activated carbon (AC). The resultant ASC provided an improved specific capacitance of 487.85 F g-1 (683 C g-1) at 1.0 A g-1. At this current density value, the energy density and the power density values were computed as to be 132.8 Wh.kg-1 and 632.39 W kg-1. The highest power density was discovered to be 6730.76 W kg-1 at 10.0 A g-1, whereas the energy density was determined as 8.75 Wh.kg-1 at this current density. The results of the work proved that CoFe2O4/GNRs nanohybrids are up-and-coming electrode active materials for advanced electrochemical energy storage and conversion technologies.