The construction of zeolitic imidazolate framework-assisted 3D-networked structure Ni-Co-S@Ni foam with ultrahigh specific capacity for advanced supercapacitors

Multivariate transition metal sulfides and porous nanosheet architectures hold promising potential for applications for the energy-related application. Nevertheless, the addition of polymer binders and conductive agents can adversely affect their electrochemical performance. In this work, we present self-assembled Ni-Co sulfide nanosheet arrays growing on foamed Ni (Ni-Co-S@NF). Ni-Co-S@NF electrode materials are synthesized through the complete sulfidation of interconnected ultrathin nanosheets derived from NiCo layered double hydroxides. The highly conductive nickel foam facilitates electron transfer while the 3D network structure promotes electrolyte diffusion and penetration. Hence, porous Ni-Co-S@NF materials presents the excellent specific capacitance as 1286.6C g−1 in 1 A g−1 and retained 70 % of its original capacity over 5000 charge–discharge cycles. Furthermore, we assemble an asymmetric supercapacitor used active carbon as negative-electrode material and Ni-Co-S@NF as positive-electrode material. This device delivers the specific energy is 74.0 Wh kg−1 and specific power of 850.0 W kg−1.