Electrochemical Performance of NiCo-MOF-Derived NiO@NiCo2O4 Nanocomposite Electrode Materials for Supercapacitors

In this study, we investigate the effect of varying tannic acid (TA) concentrations on the electrochemicalperformance of NiCo-MOF-derived nanocomposite electrode materials. The TA@NiO@NiCo 2 O 4 nanocomposites were synthesized using a straightforward metal–organic framework (MOF) templating strategy, which involved a simple hydrothermal method followed by a two-step annealing process. Electrochemical characterization reveals that the resulting nanocomposites exhibit excellent cycling stability. Among them, the sample treated with 0.02 mol L −1 TA achieves the highest specific capacitance, reaching 773 F g −1 at a current density of 1 A g −1 . Furthermore, the nanocomposites display reduced electrical impedance, with the 0.02 mol L −1 TA sample recording a series resistance (Rs) as low as 0.60 Ω. After 5000 galvanostatic charge–discharge cycles, the capacity retention of samples treated with TA concentrations of 0, 0.01, and 0.02 mol L −1 all exceed 100%, indicating remarkable electrochemical durability.