Hierarchical NiCo₂O₄@CuS composite electrode with enhanced surface area for high-performance hybrid supercapacitors

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Supercapacitors are crucial for energy storage.
• Developing high-performance electrode materials is essential.
• Nickel cobalt oxide (NiCo2O4) and copper sulfide (CuS) are promising candidates.

Purpose of the Study:

• To fabricate hierarchical binder-free NiCo2O4@CuS composite electrodes.
• To evaluate their performance as battery-type electrode materials for supercapacitors.
• To investigate the synergistic effects of NiCo2O4 and CuS.

Main Methods:

• Facile hydrothermal synthesis on nickel foam.
• Surface morphological and structural characterization.
• Electrochemical performance testing (specific capacitance, rate capability, cycling stability).

Main Results:

• Successfully fabricated hierarchical NiCo2O4@CuS composite electrodes.
• Enhanced surface area (91.38 m2 g-1) and pore structure.
• Achieved high specific capacitance (141.13 mA h g-1 at 1 A g-1).
• Demonstrated excellent rate capability and cycling stability (88.62% retention after 3000 cycles).
• Hybrid supercapacitor device achieved high energy density (28.85 W h kg-1) and stability (87.59% retention after 4000 cycles).

Conclusions:

• The NiCo2O4@CuS composite electrode exhibits superior electrochemical performance.
• Synergistic effects between NiCo2O4 and CuS enhance interfacial electron separation and transfer.
• This material is a promising candidate for advanced supercapacitor applications.