Rational design and synthesis of a 3D hierarchical NiCo-LDH/C/GF composite foam as advanced electrodes for asymmetric supercapacitors

3D honeycomb carbon coated gum-based foam (C/GF) was prepared by the mature industrial process and the subsequent one-step surface modification strategy. And it serves as conductive substrate for in-situ growth of porous NiCo-LDH derived from MOF to obtain the hierarchical NiCo-LDH/C/GF composite foam as a low-density and economical electrode material. The synergy among the various components can markedly elevate the conductivity, specific surface areas and channels for ion diffusion of the composite electrode, resulting in a high specific capacity of 1818.6 F g- 1 at 0.5 A g- 1 and outstanding rate capability. Moreover, an asymmetric NiCoLDH/C/GF//activated carbon (AC) supercapacitor could achieve a high energy density of 42.1 Wh kg- 1 at 750.5 W kg- 1, together with a stable cycling lifespan with 86.76% of capacitance retention after 8000 cycles. Our studies present a facile, green and dependable pathway for the design and synthesis of NiCo-LDH composites with satisfactory electrochemical performance.