Development of Binder‐Free Ni Foam‐Supported ZnCo 2 O 4 Electrode for Superior Supercapacitive Performance

Abstract This study employs an ecologically clean, single‐step, facile hydrothermal fabrication process to produce aesthetically pleasing shapes of ZnCo 2 O 4 as binderless electrodes on the 3D skeleton of nickel foam (Ni foam) by prolonging reaction time. The impact of reaction time on the progression of structure, morphological, and electrochemical performance was studied. The structural characteristics of the synthesized samples were analyzed using X‐ray diffraction and Raman spectroscopy. The morphological characteristics of the electrode material were studied by employing field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). X‐ray photoelectron spectroscopy (XPS) was explored about the composition and elemental state of ZnCo 2 O 4 on Ni foam electrode material. Remarkably, the 9‐h synthesized electrode material, ZCO/NF‐9 h (stacked nanosheets) was liberated specific capacitance of 2308 F/g at a scan rate of 1 mV/s, retained 95% of the initial capacitance after 5000 cycles at 50 A/g current density. The analysis through Dunn's model affirms the pseudocapacitive behavior of ZnCo 2 O 4 material deposited on the Ni foam. Furthermore, the symmetric device comprises of ZnCo 2 O 4 electrodes offers, the specific capacitance of 225 F/g, with energy and power densities of 31.25 Wh/Kg and 500 W/Kg, respectively. The innovative design and exceptional electrochemical characteristics of the stacked nanosheets of ZnCo 2 O 4 on Ni foam exhibit significant promise for electrochemical activity and future applications in energy storage devices.