NiCo2S4/Ni-Co layered double hydroxide nanocomposite prepared by a vapor-phase hydrothermal method for electrochemical capacitor application

In this work, NiCo2S4/Ni-Co layered double hydroxide (LDH) nanocomposites were prepared by using Ni-Co LDH nanosheets as precursor through a vapor-phase hydrothermal method. The NiCo2S4/Ni-Co LDH nanocomposites have a hierarchical structure in which interconnected NiCo2S4 nanosheets with smaller sizes are loaded on Ni-Co LDH nanosheets. Electrochemical performances of the NiCo2S4/Ni-Co LDH nanocomposites were measured by cyclic voltammetry and galvanostatic charge-discharge techniques. The NiCo2S4/Ni-Co LDH electrode achieved a capacity of 1765 F g−1 at 1 A g−1 and a capacity of 940 F g−1 at 10 A g−1. Control experiments showed that the capacities of the NiCo2S4/Ni-Co LDH are higher than Ni-Co LDH and NiCo2S4 nanosheets. The better electrochemical performances of the NiCo2S4/Ni-Co LDH electrode can be attributed to the unique hierarchical structure which was formed during the vapor-phase hydrothermal process.