A hybrid supercapacitor is a promising energy storage device in view of its excellent capacitive performance. Commercial three-dimensional foam nickel (Ni) can be used as an ideal framework due to an interconnected network structure. However, its application as an electrode material for supercapacitors is limited due to its low specific capacity. Herein, we report a successful growth of MnO2 on the surface of graphene by a one-step hydrothermal method; thus, forming a three-dimensional MnO2-graphene-Ni hybrid foam. Our results show that the mixed structure of MnO2 with nanoflowers and nanorods grown on the graphene/Ni foam as a hybrid electrode delivers the maximum specific capacitance of 193 F·g-1 at a current density 0.1 A·g-1. More importantly, the hybrid electrode retains 104% of its initial capacitance after 1,000 charge-discharge cycles at 1 A·g-1; thus, showing the potential application as a stable supercapacitor electrode.
