Chemical synthesis of hierarchical NiCo2S4 nanosheets like nanostructure on flexible foil for a high performance supercapacitor

Abstract

In this study, hierarchical interconnected nickel cobalt sulfide (NiCo2S4) nanosheets were effectively deposited on a flexible stainless steel foil by the chemical bath deposition method (CBD) for high-performance supercapacitor applications. The resulting NiCo2S4 sample was characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), and electrochemical measurements. XRD and X-ray photoelectron spectroscopy (XPS) results confirmed the formation of the ternary NiCo2S4 sample with a pure cubic phase. FE-SEM and HR-TEM revealed that the entire foil surface was fully covered with the interconnected nanosheets like surface morphology. The NiCo2S4 nanosheets demonstrated impressive electrochemical characteristics with a specific capacitance of 1155 F g−1 at 10 mV s−1 and superior cycling stability (95% capacity after 2000 cycles). These electrochemical characteristics could be attributed to the higher active area and higher conductivity of the sample. The results demonstrated that the interconnected NiCo2S4 nanosheets are promising as electrodes for supercapacitor and energy storage applications.

Bifunctionally active nanosized spinel cobalt nickel sulfides for sustainable secondary zinc–air batteries: examining the effects of compositional tuning on OER and ORR activity

“…0.33, 0.34, and 0.36 nm, respectively, similar to those reported by Kim and Liang for NiCo 2 S 4 . 63,64 The BET surface areas were similar for NC13, NC11, and NC31, at ca.15, 12, and 16 m 2 g −1 , respectively. 63 The composition and chemical valence states of the nickel cobalt sulfides were characterized by X-ray photoemission spectroscopy (XPS), confirming the presence of cobalt, nickel, and sulfur in all three samples.…”

Nanostructured Fe-Ni Sulfide: A Multifunctional Material for Energy Generation and Storage

“…It can be clearly seen from the CV curves in Figure 6b that FeNiS showed the highest area under CV curves at 2 mV/s compared to FeNiO and NF, leading to higher capacitance values. The capacitance increases with decreasing scan rates, which could be due to sufficient time provided for the faradic reaction representing the pseudocapacitive behavior ( Figure S5a) [43,44]. The results of the galvanostatic charge-discharge test are represented by the relationship between specific capacitance with respect to the current density in Figure 6c.…”

“…In our study, the FeNiS showed a performance with 77.3% retention after 5000 cycles in charge-discharge measurements and comparable capacitance results to several other reports (Table S4 and Figure S5c). behavior ( Figure S5a) [43,44]. The results of the galvanostatic charge-discharge test are represented by the relationship between specific capacitance with respect to the current density in Figure 6c.…”

Enhancing bifunctional catalytic activity of cobalt–nickel sulfide spinel nanocatalysts through transition metal doping and its application in secondary zinc–air batteries

“…Closer examination of some of the crystals of chromium-(NC11 Cr), manganese-(NC11 Mn), and iron-doped (NC11 Fe) samples, revealed d-spacings of the (440) planes of 0.30, 0.32, and 0.30 nm (AE0.1 nm), respectively; these are similar to values that Kim and Liang reported in the literature for NiCo 2 S 4 . 57,58 Energy-Dispersive (X-ray) Spectroscopy (EDS) mapping ( Fig. S3 †) suggested that the dopant cations were evenly distributed across the near-surface of the cobalt-nickel sulde samples.…”