Three-dimensional NiCo₂S₄ nanosheets as high-performance electrodes materials for supercapacitors

In the report, we explore a two-step efficient synthetic to purposefully fabricate three-dimensional (3D) NiCo₂S₄ nanosheets for advanced electrochemical supercapacitors. They were characterized for their structural, morphological and electrochemical properties by using XRD, SEM, TEM, cyclic voltammetry and charge discharge methods. The unique designed nanostructure exhibits a high specific capacitance (1257.1 F g⁻¹ at current density 1 A g⁻¹), good rate performance (75.7% retention for current increases around 20 times) and excellent cycling stability (80% retention at 5 A g⁻¹ after 1000 cycles). We are the first step in the synthesis of 3D NiCo₂S₄ flowers, which have a specific capacitance of 700.7 F g⁻¹ at the current density of 1 A g⁻¹ and exhibit excellent cycling stability with 95% capacitance retention. The S-NiCo₂S₄//activated carbon asymmetric supercapacitor is can deliver a maximum energy density of 47.3 W h kg⁻¹ at a power density of 477.3 W kg⁻¹. Therefore, according to our investigation it can be concluded that the low cost and environmental friendly two-step approach from 3D NiCo₂S₄ nanoflowers to the 3D NiCo₂S₄ nanosheets could be used to deposit efficient 3D NiCo₂S₄ nanosheets for supercapacitor application.