Rationally designed CuCo₂O₄@Ni(OH)₂ with 3D hierarchical core-shell structure for flexible energy storage

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• High electrochemical performance in energy storage devices requires rational electrode structures and integration.
• Flexible and binder-free electrodes are crucial for advanced energy storage applications.

Purpose of the Study:

• To fabricate a flexible, binder-free CuCo2O4@Ni(OH)2 nanosheet electrode on carbon cloth for high-performance energy storage.
• To investigate the electrochemical properties of the novel core-shell structured composite electrode.
• To assemble and evaluate a flexible all-solid-state asymmetric supercapacitor (FAASC) using the developed electrode.

Main Methods:

• Fabrication of a heterogeneous core-shell CuCo2O4@Ni(OH)2 nanosheet structure on carbon cloth.
• Electrochemical characterization of the composite electrode, including specific capacitance and rate capability measurements.
• Assembly of a flexible all-solid-state asymmetric supercapacitor using CuCo2O4@Ni(OH)2/carbon fiber cloth and activated carbon/carbon fiber cloth.

Main Results:

• The CuCo2O4@Ni(OH)2/carbon fiber cloth (CFC) electrode achieved a specific capacitance of 2160 F/g at 1 A/g with 82.7% retention at 20 A/g.
• The assembled FAASC demonstrated high energy density (58.9 Wh/kg) and power density (400 W/kg) with good long-term cycling stability.
• The device successfully powered a blue light-emitting diode after a short charge, showcasing practical application potential.

Conclusions:

• The hierarchical core-shell structure of CuCo2O4@Ni(OH)2 nanosheets on CFC provides a large surface area, enhancing electrochemical performance.
• The binder-free composite electrode and FAASC exhibit excellent potential for flexible high-performance energy storage devices.
• This fabrication method offers a promising route for developing advanced electrode materials for next-generation energy storage.