Regulating the core/shell electric structure of Co3O4@Ni-Co layered double hydroxide on Ni foam through electrodeposition for a quasi-solid-state supercapacitor.

A flower-like structured electrode material of Co3O4@Ni-Co layered double hydroxide (LDH) grown on Ni foam (Co3O4@Ni-Co LDH/NF) was prepared via anin situgrowth, annealing and electrodeposition process. The Co3O4@Ni-Co LDH/NF electrode was prepared with the optimized conditions of annealing temperature 300 °C, deposition time 20 min and Ni/Co ratio 1:1. The results showed that the as-prepared electrode material exhibited an excellent specific capacitance and great cycling stability. Furthermore, an quasi-solid-state supercapacitor was assembled using the prepared Co3O4@Ni-Co LDH/NF as the positive electrode and activated carbon on Ni foam (AC/NF) as the negative electrode. The as-assembled device presented a high energy density and power density.