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An interconnected honeycomb-like structure of the HLPBC/NiCo2O4 composite was successfully prepared by carbonization combined with a facile hydrothermal process.

Given the exceptional specific surface area, geometry, and periodic porosity, transition-metal sulfides derived from crystalline metal−organic frameworks have spurred great interest in energy storage systems. Herein, employing a different sulfurization process, well-aligned NiCo 2 S 4 and CoS 2 nanoarrays with a hollow/porous configuration derived from pentagon-like ZIF-67 are successfully designed and constructed on Ni foam. The hollow/porous structure grown on a conductive matrix can significantly improve electroactive sites, shorten charge/ion diffusion length, and enhance mass/electron transfer. Consequently, the obtained NiCo 2 S 4 possesses an excellent specific capacitance of 939 C/g, a fast charge/ discharge rate, and a favorable life span. An advanced asymmetrical supercapacitor is fabricated by engaging NiCo 2 S 4 and CoS 2 as cathode and anode materials, respectively, with a well-separated potential window. The obtained device delivers an exceptional energy density of 55.8 W h/kg at 695.2 W/kg, which is highly considerable to the recent transition metal sulfide-based devices. This facile tactic could be employed to construct other electrode materials with superior electrochemical properties.

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.