Macroporous C@MoS2 composite as anodes for high-performance sodium-ion batteries

Abstract

Sodium-ion batteries (SIBs) are considered promising energy storage devices and substitutes for lithium-ion batteries in the near future, and their anode materials play crucial roles in their electrochemical performance. Molybdenum disulfide (MoS₂) has attracted significant attention as an SIB anode material owing to its high theoretical capacity (670 mA h g⁻¹) and 2D structure with a large layer space (0.65 nm vs. 0.33 nm of graphite). In this work, 3D polystyrene (PS) microspheres were adopted as sacrificial templates to construct a hierarchical macroporous C@MoS₂ composite, which has rarely been reported for SIB anodes. This unique design synergistically integrated conductive macroporous carbon networks with 2D-layered MoS₂, enabling super Na⁺ storage capability and unprecedented cycling stability in SIBs. In particular, a capacity of 438 mA h g⁻¹ after 100 cycles at a current density of 500 mA g⁻¹ and a capacity of 319.4 mA h g⁻¹ after 1000 cycles at 1000 mA g⁻¹ were achieved owing to its unique macroporous structure. Furthermore, the high electronic conductivity, large surface area, and rich Na⁺ diffusion channels all benefit for its super capacity and stability.