▎ 摘　　要

Transition metal oxides/graphene nanosheets based materials have been emerging as potential electrodes for supercapacitors. For this purpose, two hybrid compositions consisting of Mn0.06Co2.94O4 anchored on carbon nanotubes (CNTs) and hydrothermally reduced graphene oxide (HrGO) are synthesized by a facile solvothermal technique, and their electrochemical properties are compared with pure Mn0.06Co2.94O4 and Co3O4. The highly crystalline structure, well-defined, well-ordered, and in particular, electrochemically favorable morphologies are achieved. As a supercapacitor electrode, the hybrid electrode with HrGO delivered a high specific capacitance of 933 F/g at a current density of 4 A/g. Further, an exceptional energy density of 55 Wh/kg along with a remarkable power density of 9 kW/kg at 8 A/g has been achieved for HrGO hybrid electrode. Additionally, Mn0.06Co2.94O4 hybrid with CNTs also exhibited brilliant characteristics in terms of energy and power density, where it showed the highest specific capacitance of 950 F/g and remarkable energy density of 33 Wh/kg at 4 A/g but delivered moderate power density. The graphene-based hybrid showed an excellent cyclic life and retained 82% capacitance after 33,000 charge-discharge cycles. The phenomenal performance of graphene-based hybrid is attributed to the synergistic effect between metal oxides and highly conductive graphene sheets.