High-capacity Sb and MoS₂ were successfully encapsulated carbon nanofibers (Sb@MoS₂@CNFs) via facile electrospinning and subsequent thermal treatment, which showed enhanced sodium storage capacity, superior cycling stability and rate capability. The integration of the Sb/MoS₂ with CNFs ensured good Na⁺ ions diffusion, enhanced ion/electron transport, and buffered the volume expansion, leading to the excellent sodium storage performance.

Abstract

Metallic antimony (Sb) and molybdenum disulfide (MoS₂) are identified as promising anode materials for sodium ion batteries (SIBs) owing to their high theoretical capacities. Herein, both Sb and MoS₂ are integrated and fully embedded into carbon nanofibers (CNFs) to form Sb/MoS₂@CNFs nanocomposite via an electrospinning technique followed by heat treatment. When employed as anode material for SIBs, the Sb/MoS₂@CNFs electrode presents a reversible capacity of 282.7 mAh g⁻¹ after 300 cycles at 1 A g⁻¹, and even 197.5 mAh g⁻¹ after 1350 cycles at a high current density of 5 A g⁻¹. The superior sodium storage performance of the Sb/MoS₂@CNFs can be ascribed to the synergistic effect of the integrated Sb/MoS₂ components and their full encapsulation into the one-dimensional (1D) conductive carbon nanofibers. The well-dispersed Sb/MoS₂ nanoparticles ensure good Na⁺ ions accessibility and high storage capacity, while 1D nanostructure facilitates ion/electron transport, tolerates the volume expansion, and prevents the Sb/MoS₂ nanoparticles from aggregating during cycling. This work provides a simple and efficient synthetic route of multicomponent anode materials in advanced SIBs.