Uniform ReS2 porous nanospheres assembled from curly ReS2 few-layers with an expanded interlayer spacing for high-performance lithium-ion batteries

A facile hydrothermal method has been exploited to synthesize the uniform ReS2 three-dimensional hierarchical nanospheres assembled from few-layered ReS2 nanosheets with expanded interlayers (designated as porous NSs), resulting in a lot of large pores formed from the curly ReS2 nanosheets. The expanded interlayers of the ReS2 porous NSs could accommodate more lithium ions and facilitate lithium ion transports. Especially notable is that the large void spaces in the three-dimensional hierarchical nanospheres is very favorable for buffering the volume expansion, very much favoring the preservation of the electrode integrity during the lithiation/delithiation process. When evaluated as anode materials for lithium-ion batteries at a current density of 100 mA g(-1) after 100 cycles, the unique ReS2 porous NSs deliver a remarkably enhanced reversible capacity of 1011 mAh g(-1) with a capacity retention of over 100%, which is significantly superior to the ReS2 solid microparticles (solid MPs) with a capacity of 458 mAh g(-1) and a capacity retention of merely 75%. The very high reversible capacity is indicative of the robustness of the present ReS2 porous NSs as high-performance anodes for lithium-ion batteries, which may pave the way to further study the three-dimensional self-assembly of two-dimensional layered materials towards the superior electrochemical energy storage.