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

•One-step and low-temperature synthesis method is developed to produce NiCo2S4.•Ultrathin NiCo2S4 nanosheets are grown directly on Ni foams as binder-free anodes.•The NiCo2S4–Ni anode delivers a high specific capacity of 1368 mAh g−1.•The anode exhibits excellent cycling stability and high-rate capability.

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.

Graphical abstractA novel one-step and low-temperature approach is developed to directly grow ultrathin NiCo2S4 nanosheets on Ni foam, showing outstanding Li-ion storage performance.Figure optionsDownload full-size imageDownload as PowerPoint slide