| Summary: | Honeycomb-like Ni(OH)<sub>2</sub>/Ni<sub>3</sub>S<sub>2</sub>/Ni foam (NF) was fabricated via a two-step hydrothermal process and subsequent alkalization. Ni<sub>3</sub>S<sub>2</sub> with a honeycombed structure was in-situ synthesized on the NF surface by a hydrothermal process. MOF-derived Ni(OH)<sub>2</sub> nanosheets were then successfully grown on the Ni<sub>3</sub>S<sub>2</sub>/NF surface by a second hydrothermal process and alkaline treatment, and a large number of nanosheets were interconnected to form a typical honeycomb-like structure with a large specific surface area and porosity. As a binder-free electrode, the prepared honeycomb-like Ni(OH)<sub>2</sub>/Ni<sub>3</sub>S<sub>2</sub>/NF exhibited a high specific capacitance (2207 F·g<sup>−1</sup> at 1 A·g<sup>−1</sup>, 1929.7 F·g<sup>−1</sup> at 5 mV·s<sup>−1</sup>) and a remarkable rate capability and cycling stability, with 62.3% of the initial value (1 A·g<sup>−1</sup>) retained at 10 A·g<sup>−1</sup> and 90.4% of the initial value (first circle at 50 mV·s<sup>−1</sup>) retained after 5000 cycles. A hybrid supercapacitor (HSC) was assembled with Ni(OH)<sub>2</sub>/Ni<sub>3</sub>S<sub>2</sub>/NF as the positive electrode and activated carbon (AC) as the negative electrode and exhibited an outstanding energy density of 24.5 Wh·kg<sup>−1</sup> at the power density of 375 W·kg<sup>−1</sup>. These encouraging results render the electrode a potential candidate for energy storage.
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