Hierarchical 3D starfish-like Ni3S4–NiS on reduced graphene oxide for high-performance supercapacitors

Abstract

In this research, Ni3S4–NiS with starfish morphology was synthesized with a simple hydrothermal method and then hybridized with reduced graphene oxide (rGO) as a material for high-performance supercapacitors. The crystal structure and morphology of the as-prepared materials were studied by X-ray diffraction spectroscopy and electron microscopy. Uniform distribution of Ni3S4–NiS on rGO was observed from electron microscopy images. The results showed that Ni3S4–NiS/rGO with a specific capacitance of 1578 Fg-1 and discharge time of 603 s at the current density of 0.5 Ag-1 has more capacity and stability relative to Ni3S4–NiS. The cyclic stability after 5000 cycles showed that the Ni3S4–NiS/rGO electrode is stable, and 91% of its corresponding initial capacitance retained at the end of 5000 cycles. The good results in capacitance and stability of this electrode can be regarded as an improvement for the development of highly efficient and economic supercapacitors for portable electronic devices.