Hierarchical Structured Ni₃S₂@rGO@NiAl-LDHs Nanoarrays: A Competitive Electrode Material for Advanced Asymmetrical Supercapacitors

Abstract

In this account, a well-aligned hierarchical nickel sulfide@reduced graphene oxide@nickel aluminum layered double hydroxides composite (denoted as Ni3S2@rGO@NiAl-LDHs) supported on a Ni-foam substrate is successfully designed and constructed via a successive hydrothermal process. Ni3S2 nanorod arrays grown on Ni foam could provide large open space and short ions diffusion path. Graphene with high specific surface area and excellent conductivity can effectively transfer charges; NiAl-LDHs has large contact area with electrolyte, thus enabling a fast and reversible redox process, which could improve the specific capacitance. As a consequence, the Ni3S2@rGO@NiAl-LDHs fulfills superior specific capacity, pleasurable charge–discharge rate, and outstanding lifespan. Moreover, an advanced asymmetrical device is assembled by employing Ni3S2@rGO@NiAl-LDHs and rGO@Fe3O4-C, which delivers high specific capacity (201.3 F g–1) and exceptional energy density (71.7 Wh kg–1). The well-aligned Ni3S2@rGO@NiAl-LDHs could provide a promising conception constructing hierarchical structural materials in the area of supercapacitors.