Bimetallic sulfides SnS/FeS particles anchored on tremella-like carbon as advanced anode material for sodium ion storage

Sodium-ion batteries (SIBs) are considered as the most promising alternatives to lithium-ion batteries (LIBs). The design of electrode materials is crucial to the improvement of the electrochemical performance of SIBs. In this work, the multicomponent sulfides SnS@FeS particles anchored on tremella-like carbon (SnS@FeS/C) are rationally engineered and constructed. The bimetallic sulfides SnS@FeS particles can provide abundant redox active sites and distinguished electronic structures. Simultaneously, the three-dimensional interconnected carbon with tremella-like structure mitigates the volume expansion and enhances the conductivity. Benefiting from the compositional and structural advantages, the SnS@FeS/C composite achieves high reversible capacity (410.1 mAh g(-1) at 100 mA g(-1)) and excellent rate capability (300.7 mAh g(-1) at 3000 mA g(-1)) in SIBs. Notably, it also exhibits ultralong cycling performance (360 mAh g(-1) after 1000 cycles). Additionally, the kinetic analyses of redox reaction reveal that the pseudo-capacitance behavior dominates the charge/discharge process of SnS@FeS/C electrode. This work provides a strategy for preparation of multicomponent metal sulfides with three-dimensional carbon network for excellent electrochemical performance, paving the way for the potential applications in energy storage fields.