Influence of temperature on the redox behaviour of binder-free CNTs-NiZnS electrode and the application in efficient energy storage devices

Abstract

Abstract Due to their unique structure, the metal sulfides are mechanically stable, have higher conductivities, and are frequently used in energy storage devices. Here, binder-free electrodes were designed by depositing the nickel zinc sulfide (NiZnS) incorporated with carbon nanotubes (CNTs) on the nickel foam (NF). X-ray diffraction (XRD) was used to describe the crystallinity of produced CNTs-NiZnS nanostructures, and morphological investigations were performed using field emission scanning electron microscopy (FESEM). According to the electrochemical measurements, the heating of electrolyte at 80 °C resulted in considerably enhanced specific capacitance of 1475 Cg−1 (50.85 F m−2) and 666 Cg−1 (13.77 F m−2) at 1 and 2 Ag−1 current density, correspondingly. Thus demonstrating a good capacity retention of 47% at 2 Ag−1. The supercapattery (CNTs-NiZnS//AC) was designed with CNTs-NiZnS and AC, providing a specific charge capacity of 212 Cg−1 (at 2.0 Ag−1) along with energy density of 51 Wh-kg−1 at 820 W kg−1 power density. The stability of CNTs-NiZnS//AC was tested by subjecting it to 5000 successive cycles.