Encapsulating tin disulfide nanoparticles in carbon nanofibers for durable sodium storage

Abstract

Due to its unique layered structure and high theoretical capacity, tin disulfide (SnS₂) is regarded as a promising anode material for sodium-ion batteries. However, its practical application has been hindered by relatively poor conductivity and severe volumetric changes during cycling. Herein, carbon nanofiber encapsulated SnS₂ nanoparticles, SnS₂@CNF, has been synthesized via a gaseous sulfidation process from a Sn-based metal-organic compound (Sn-MOC)@PAN electrospun precursor. Benefiting from precise control of the SnS₂ particle size, sodium-ion transport has been facilitated with superior sodium storage performance. The SnS₂@CNF anode exhibits long-term cycling stability (457 mAh g⁻¹ after 1500 cycles at 5 A g⁻¹) and high reversible capacity (661 mAh g⁻¹ after 100 cycles at 0.5 A g⁻¹). When paired with the Na₃V₂(PO₄)₃ cathode, the SnS₂@CNF//NVP presented an energy density of 161 Wh kg⁻¹, indicating its significant potential for practical applications.