Unleashing the potential of self-assembled binder-free NiCoLDH nanosheets for supercapacitor

Nowadays, interest goes on increasing in the synthesis and development of layered hydroxide-based supercapacitive materials. Focusing on this, we have prepared nickel–cobalt layered double hydroxide (NiCoLDH) electrode on stainless steel (SS) substrates via one-step hydrothermal method. In this typical synthesis, reaction time variation route was adopted and effect of hexamethylenetetramine (HMT) on the growth of NiCoLDH nanosheets were thoroughly tested. X-ray diffraction (XRD) analysis of NiCoLDH electrodes reveals rhombohedral-like crystal structure. SEM images interpreted that the addition of HMT results in unique nanosheets-like morphology. BET analysis provides 5.87 m²/g specific surface area for optimized NiCoLDH material. Furthermore, the NiCoLDH electrode delivered the maximum specific capacitance of 534 F/g at 1 mA/cm² along with 42.72 Wh/kg and 384.48 W/kg energy and power densities, respectively. The NiCoLDH electrode is capable to deliver 78.12% cyclic stability over 2,000 CV cycles at 100 mV/s. This work implies that the nanosheets-like NiCoLDH will be suitable for upcoming energy storage applications.