Hierarchical NiCo2O4@nickel-sulfide nanoplate arrays for high-performance supercapacitors

•Hierarchical NiCo2O4@ nickel-sulfide nanoplate arrays were prepared.•The array electrode shows good integrity and porosity.•The array electrode exhibits an improved areal capacitance of 1.85 F cm−2 at 8 mA cm−2.

Electrodeposition of nickel sulfide (Ni–S) on NiCo2O4 (NiCo2O4@Ni–S) nanoplate arrays produces a new hierarchical core–shell functional-material. Weak crystalline Ni–S nanosheets have been uniformly coated on the NiCo2O4 nanoplate array obtained by hydrothermal growth. When tested as an electrode for supercapacitors, the NiCo2O4@Ni–S nanoplate arrays have been found to exhibit a significantly improved areal capacitance of 1.85 F cm−2 at a current density of 8 mA cm−2, good rate capability and cycling stability. In addition, the capacitance fading of the NiCo2O4@Ni–S arrays are attributed to the surface coarsening of the Ni–S nanosheets.

Graphical abstractNickel sulfide on NiCo2O4 core–shell nanoplate arrays are fabricated and show good energy density and cycling stability for supercapacitors.Figure optionsDownload full-size imageDownload as PowerPoint slide