Ultrathin graphene@NiCo2S4@Ni-Mo layered double hydroxide with a 3D hierarchical flowers structure as a high performance positive electrode for hybrid supercapacitor

Abstract

This study presents three-dimensional flower-like spheres composed of NiCo2S4@Ni-Mo layered double hydroxide (LDH) nanocomposites, which are grown in situ on reduced graphene oxide (RGO). The RGO@NiCo2S4@NiMo-LDH nanocomposites exhibit remarkable electrochemical properties and have a specific capacitance of 1346 F g−1 at the current density of 1 A g−1. In addition, using RGO@NiCo2S4 @NiMo-LDH hybrid nanosheets and activated carbon (AC) as the positive and negative electrodes, the asymmetric supercapacitor device was successfully assembled, and it showed a significant energy density of 59.38 Wh kg−1 at a power density of 808.19 W kg−1, with good cycle stability. The initial capacity retention rate is 80 % after 10,000 cycles. These results demonstrate the great potential of the synthesized RGO@NiCo2S4@NiMo-LDH composite for the development of high-performance electrode materials for supercapacitors.