Synergistically Driven CoCr-LDH@VNiS₂ as a Bifunctional Electrocatalyst for Overall Water Splitting and Flexible Supercapacitors

Abstract

Utilizing alternative energy sources to fossil fuels has remained a significant issue for humanity. In this context, efficient earth-abundant bifunctional catalysts for water splitting and energy storage technologies like hybrid supercapacitors have become essential for achieving a sustainable future. Herein, CoCr-LDH@VNiS 2 was synthesized by hydrothermal synthesis. The CoCr-LDH@VNiS 2 catalyst entails 1.62 V cell voltage to reach the current density of 10 mA cm −2 for overall water splitting. The CoCr-LDH@VNiS 2 electrode illustrates a high electrochemical specific capacitance (Csp) of 1380.9 F g −1 at a current density of 0.2 A g −1 and an outstanding stability with 94.76% retention. Moreover, the flexible asymmetric supercapacitor (ASC) achieved an energy density of 96.03 W h kg −1 @0.2 A g −1 at a power density of 539.98 W kg −1 with remarkable cyclic stability. The findings provide a new approach toward the rational design and synthesis of bifunctional catalysts for water splitting and energy storage.

Hydrothermal Prepared Bramble-like Double Arrays NiCo2S4 Bifunctional Electrocatalysts for High-Efficiency Water Splitting

“…The optimized energy level alignment caused by Co and introduced more active sites caused by its unique 3D bramble-like structure imported better structural stability with higher electronic transfer abilities and showed higher electrochemical activity. Importantly, the performance of NiCo 2 S 4 /NF catalyst was superior to some recently reported bifunctional electrocatalysts as shown in Figure d − and furthermore certified that the NiCo 2 S 4 /NF catalyst had an excellent electroceutical ability.…”

Tuning the Activity and Stability of CoCr-LDH by Forming a Heterostructure on Surface-Oxidized Nickel Foam for Enhanced Water-Splitting Performance

“…On the other hand, various Ni-based materials, especially NiX (X = O, S, Se, P, etc. ), have shown promising electrocatalytic performance toward the water-splitting reaction. ,− Among these, NiO is preferred in terms of ease of preparation and moderate activity. Although it has optimal active sites on the surface for the adsorption of hydroxide and various intermediates, it possesses a very low electrochemically active surface area, which results in poor mass transfer properties.…”

In Situ Fabrication of Hierarchical CuO@CoNi-LDH Composite Structures for High-Performance Supercapacitors

“…Li et al synthesized petal-like nickel–aluminum LDH and demonstrated excellent performance of supercapacitor. However, the full potential of LDH performance has not been exploited, which derives from poor conductivity, structure agglomeration, and undermining. , To tackle these challenges, researchers have proposed various approaches, including interlayer engineering, − defect engineering, − heterostructure engineering, − and ternary engineering by introducing a third transition metal element to improve the material’s structure. − In these studies, in situ growth on a current collector presents a more promising strategy. Chen et al constructed the in situ growth of cobalt–nickel LDH nanosheets on the nickel foam with a growth promoter of hexadecyltrimethylammonium bromide.…”