Hierarchical NiCo₂S₄@Ni₃S₂ core/shell nanorod arrays supported on carbon cloth for all-solid-state flexible asymmetric supercapacitors

Flexible electrodes for preparing core–shell structures are receiving increasing attention. A composite electrode material with NiCo₂S₄ as the core and Ni₃S₂ as the shell was successfully synthesized by hydrothermal synthesis and electrodeposition method. The prepared flexible NiCo₂S₄@Ni₃S₂ core/shell nanorod array has higher electrochemical performance, with specific capacitance of 5.714 F cm⁻² at 2 mA cm⁻² and excellent cycle stability. In addition, the prepared flexible hybrid supercapacitor has been assembled with NiCo₂S₄@Ni₃S₂ as the positive electrode and Fe₂O₃-rGO as the negative electrode, delivering an energy density of 5.9 mWh cm⁻³ at 171 mW cm⁻³. These results make the NiCo₂S₄@Ni₃S₂ a high-performance supercapacitor application candidate.