Binder free electrodeposition fabrication of NiCo2O4 electrode with improved electrochemical behavior for supercapacitor application

The supercapacitor is a ground-breaking energy storage device that has exploded in popularity in recent decades. The present study demonstrated a binder-free electrodeposition technique to produce NiCo2O4 for two different deposition times, namely 6 min (NC6) and 10 min (NC10). The cubic phase and purity of manufactured samples were validated by X-ray diffraction (XRD) patterns. Scanning Electron Microscopy (SEM) analysis revealed a flower-like arrangement in the NC6 sample and a sea-coral morphology in the NC10 sample. The electrochemical characteristics of NC6 and NC10 samples are tested using three- and two-electrode systems. The results showed that the NC6 sample had an extremely high specific capacitance value of 1472 F/g at 1.0 mV/s scan rate. The galvanostatic charge-discharge (GCD) study demonstrates that NC6 and NC10 have a rate-performance of 88.47 and 90.81% at a higher current density of 10.0 A/g, respectively. Outstanding cycle stability with 129% retention is observed for the two-electrode setup, which was 83% for NC6 and 81% for NC10 in the three-electrode system. The simple manufacturing method and outstanding performance of NiCo2O4 electrodes open-up new opportunities in the field of energy.