| Summary: | Transition metal sulfides (TMSs) are considered as attractive materials in the areas of energy storage because of their unique redox properties, excellent electronic conductivity, as well as environmental friendliness. However, poor cyclic stability and limited electrochemical active sites hinder their further application. To address this issue, a flower-like hierarchical CuCo<sub>2</sub>S<sub>4</sub> structure is constructed by a two-step hydrothermal method. In this nanostructure, CuCo<sub>2</sub>S<sub>4</sub> grows outward to form a tightly bound hierarchical structure on the nickel foams (NFs). This oriented structure can provide more laminar gaps for electrolyte ion diffusion, exposing more reaction sites to increase the ion transport efficiency between the layers, reducing the ion transport resistance and improving the reaction kinetics. Thus, the CuCo<sub>2</sub>S<sub>4</sub> electrode exhibits excellent energy storage performance, exhibiting a high specific capacity of 1415.6 F g<sup>−1</sup> at 1 A g<sup>−1</sup>. After 10,000 cycles of 10 A g<sup>−1</sup>, it still has 91.9% of the initial performance. In addition, an asymmetrical supercapacitor (ASC) was constructed by choosing CuCo<sub>2</sub>S<sub>4</sub> as the anode and RGO as the cathode, which has the maximum energy density (61.8 Wh Kg<sup>−1</sup>) at 812.1 W Kg<sup>−1</sup> and significant cycling endurance (92.05% retention) at 10,000 turns. Briefly, the researchers successfully constructed an array of CuCo<sub>2</sub>S<sub>4</sub> flower-like hierarchical nanostructures and confirmed their potential application in supercapacitors.
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