Interconnected NiS nanosheets supported by nickel foam: Soaking fabrication and supercapacitors application

In this article, interconnected and staggered nickel sulfide nanosheets grown on nickel foam have been successfully prepared by an ultrasound-assisted soaking method using nickel hydroxide nanosheets as precursor. As electrode material for supercapacitor, the nickel sulfide nanosheets are characterized by cyclic voltammetry (CV), galvanostatic charge–discharge and electrochemical impedance spectroscopy (EIS) measurements. Owing to the unique structure, the nickel sulfide nanosheets exhibit excellent electrochemical performance, including high area capacitances (2.64   F   cm −2 ) and remarkable cycling stability (90% retaining after 2000 cycling). Therefore, such a novel and facile synthetic route to synthesis the high-performance nickel sulfide nanosheets may open a new pathway to prepare sulfide materials with distinctive nanostructures and outstanding electrochemical performance. At the same time, asymmetric supercapacitor is fabricated with NiS-NF as positive material and active carbon as negative material. The asymmetric supercapacitor shows excellent long-term electrochemical stability and high energy density. All these results illustrate that the NiS-NF electrode is promising for potential application in supercapacitors and other fields.