Structural and electrochemical characteristics of FeSn3S8@C composite anodes for lithium-ion batteries

In this study, FeSn 3 S 8 @C composite material, a potential anode material for lithium-ion batteries, was synthesized by dispersing FeSn 3 S 8 particles into a phenolic resin solution via a hydrothermal method. The resulting product was then centrifuged, followed by carbonization in a muffle furnace and drying. Characterization results reveal that the resulting FeSn 3 S 8 @C composite consists of flake-like structures with diameters ranging from 50 to 200 nm and an average thickness of approximately 5 nm. The surfaces of these flakes are uniformly coated with a carbon layer derived from the dehydration and curing of phenolic resin. Electrochemical tests demonstrate that the FeSn 3 S 8 @C composite delivers an initial specific capacity of 1364.9 mAh g −1 and exhibits significantly enhanced cycling stability and coulombic efficiency compared to the pristine FeSn 3 S 8 . Its capacity retention rate has increased by more than 20%. The incorporation of the organic carbon layer effectively alleviates structural degradation during repeated charge/discharge cycles and improves lithium-ion diffusion coefficient. Although the carbon coating slightly reduces the initial discharge capacity, it ultimately leads to superior overall electrochemical performance by mitigating structural decay and enhancing ion transport.