High-performance asymmetric supercapacitor electrode materials NiCo₂S₄@NiCo-LDH@Ni foam

Composite electrode materials often have excellent electrochemical properties; however, their preparation often requires multiple steps. Therefore, to further reduce the time and preparation cost, a NiCo₂S₄@NiCo-layered double hydroxide (NiCo-LDH) composite electrode material was prepared by a one-step method in this study. In the three-electrode system, the specific capacitance was 7462.5 mF cm⁻² at a current density of 5 mA cm⁻². Moreover, the specific capacitance was maintained at 78.4% after 6000 cycles. To further verify its practical application, we assembled an asymmetric supercapacitor using activated carbon as the anode material and NiCo₂S₄@NiCo-LDH as the positive material. The results show that the capacity of the device can still be maintained at 80% of its original capacity after 5000 cycles. This shows that the NiCo₂S₄@NiCo-LDH@NF electrode material has good application prospects.