Supercapacitor performance of a nanocomposite of dilithium and β-NiS

In this report, binary nanocomposite of Li 2 -incorporated β-NiS has been successfully synthesized via the hydrothermal technique. The formation of Li 2 and rhombohedral β-NiS nanocomposite, spongy layered flakes morphology, and elemental analysis was characterised by performing XRD, SEM, and energy-dispersive X-ray analysis, respectively. The charge storage capability of the Li 2 : β-NiS nanocomposite was examined in the three-electrode configuration. The voltammetric curve from cyclic voltammetry and charge–discharge plateaus from Galvanostatic charge/discharge measurements shows the Li 2 : β-NiS exhibits pseudocapacitive behaviour. The Li 2 : β-NiS electrode delivers exceptional specific capacitance of 800 F g −1 at 10 mV s −1 and remarkable cyclic stability of 90% after 3000 continuous charge–discharge cycles at 10 mA cm −2 . In addition, a symmetric device has been assembled with Li 2 : β-NiS nanocomposite electrode. The performance of a symmetric device has been studied in a window of 1 V with a lower end at 0.5 V. (0.5 to 1.5 V). It is examined that the device exhibits good energy density and power density of 12 Wh Kg −1 and 500 W Kg −1 , respectively. The symmetric device could yield 94% capacity retention after 5000 continuous charge–discharge cycles at a current density of 15 mA cm −2 . From this report, the electrochemical performance of Li 2 : β-NiS electrode suggests it can be a promising electrode for high-performance supercapacitors.