A High-Performance Nanoflower MnCo ₂ O ₄ /ZnCo Layered Double Hydroxide Electrode Supported on Ni Foil for Advanced Asymmetric Supercapacitors

Combining metal oxides with layered double hydroxides (LDHs) makes a unique approach to produce new nanomaterials for energy storage applications viable. The MnCo2O4/ZnCo LDH nanoflowers are grown using a two-step hydrothermal and reflux condensation technique on the inexpensive, readily available substrate nickel foil (Ni foil). The advantageous structure of the electrode provides a high surface area, which is beneficial for improved electrochemical performance through a synergistic effect in the MnCo2O4/ZnCo LDH electrode. From the optimized condition in the three-electrode system, the electrode exhibits a specific capacitance of 1253.3 F g–1 at a current density of 15 mA cm–2 and greater stability. By using MnCo2O4/ZnCo LDH as a positive electrode and activated carbon (AC) as a negative electrode, an amazing solid-state asymmetric supercapacitor device is developed. The device possesses an energy density of 55.9 Wh kg–1, power density of 5.2 kW kg–1, and cyclic stability of 87.67% retention after 5000 cycles. With excellent performance, our study offers a new platform for the electrochemical application of nanoflower MnCo2O4/ZnCo LDH.