Hierarchical flower SnS₂/C composites for long-cycle and high-rate sodium ion batteries

Tin-based are considered ideal anode materials for sodium ion batteries (SIBs) due to their high-theoretical capacity and low cost, among which tin disulfide (SnS₂) has been the most widely studied. Here, hierarchical flower SnS₂ were prepared by a simple one-step solvothermal method, and SnS₂@C was synthesized by carbonization after stirring with dopamine. It is precisely because of this special morphology that the material itself has a larger buffer space, which effectively improves the volume expansion problem, and the composite with carbon materials also greatly improves the poor electrical conductivity of the sulfide itself, serious volume expansion, polysulfide dissolution and other problems. When applied in SIBs anode, hierarchical flower SnS₂ structure showed excellent specific capacity of 180.8 mA h g⁻¹ after 500 cycles at a high current density of 5 A g⁻¹. This work provides a new route for realizing high-capacity and long-cycle SnS₂@C composite in SIBs anode.