One-step synthesis of NiCo₂S₄ ultrathin nanosheets on conductive substrates as advanced electrodes for high-efficient energy storage

A simple one-step and low-temperature synthesis approach has been developed to grow hierarchical NiCo₂S₄ ultrathin nanosheets (2-3 nm in thickness) on Ni foam. Owing to the unique nanoarchitecture, the NiCo₂S₄ nanosheets not only offer abundant electro-active sites for energy storage, but also have good electrical and mechanical connections to the conductive Ni foam for enhancing reaction kinetics and improving electrode integrity. When used as anodes for Li-ion batteries, the NiCo₂S₄ nanosheets demonstrate exceptional energy storage performance in terms of high specific capacity, excellent rate capability, and good cycling stability. The mild-solution synthesis of NiCo₂S₄ nanostructures and the outstanding electrochemical performance enable the novel electrodes to hold great potential for high-efficient energy storage systems.