Two-Dimensional Cu₂MoS₄-Loaded Silicon Nanospheres as an Anode for High-Performance Lithium-Ion Batteries

Silicon-based anode materials have a theoretical capacity 10 times that of commercial graphite and have attracted attention. Herein, a creative and effective strategy is elaborated for the synthesis of composite Cu2MoS4/SiNS materials through the self-assembly of silicon nanospheres and a two-dimensional Cu2MoS4 material. The porous silicon dispersed in the two-dimensional layered structure can effectively release the volume expansion and mechanical stress generated, which can also provide further active sites and fast channels for Li+ transmission, and improve the conductivity of the material. As expected, when used as the anode of lithium-ion batteries, the Cu2MoS4/SiNS material exhibited a highly improved electrochemical performance. Benefitting from the unique structural features, the Cu2MoS4/SiNS material showed a discharge specific capacity of 1920 mAh g–1 at 100 mA g–1 and an excellent rate capability of 1330 mAh g–1 at 1.0 A g–1 after 100 cycles. When the current density was further increased to 2.0 A g–1 to test the fast charging performance of the Cu2MoS4/SiNS material, we obtained a specific capacity of 1180 mAh g–1 with 69.2% capacity retention that could still be maintained after 400 cycles. The ultrastable properties and superior capacity of the composite material provide the potential direction for the construction of high-performance lithium-ion batteries.