In-situ facile synthesis of flower shaped NiS_2@regenerative graphene oxide derived from waste dry battery nano-composites for high-performance supercapacitors

摘要

Regenerative graphene oxide (Re-GO) with two-dimensional loose structure is obtained from carbon rods of waste dry batteries by freeze-drying post-processing method. This not only reduces resource waste but also generates a new device for energy storage. Transition metal sulfides are in-situ grown on Re-GO surface as high-performance electrode material for supercapacitors. Facile synthesis of the three-dimensional nanoflower structure Re-GO@NiS2 shows many excellent electrochemical properties, combining the stability of the carbon material and high specific capacitance of transition metal sulfides. The maximum specific capacitance is 1932.5 F.g(-1) at a current density of 1 A.g(-1) in a three-electrode system. Furthermore, as-assembled Re-GO@ NiS2//Re-GO assymmetric supercapacitor (ASC) exhibits the specific energy of 28.31 Wh.kg(-1) at specific power of 800 W.kg(-1). As a result, this work provides an effective route to dispose of waste dry battery and regenerate it for supercapacitor applications.