Polycrystalline Fe- and Sn-based sulfides for high-capacity sodium-ion battery anodes.

Nano-polycrystalline Sn 2 S 3 /Sn 3 S 4 /FeS/Fe 7 S 8 sulfides anchored on graphene were synthesized via annealing SnS 2 and Fe followed by homogeneously combining them with exfoliated graphite. When applied as an anode for a sodium-ion battery, the reversible capacity reached 863 mA h g -1 at 100 mA g -1 . This facial materials synthesis method may be applied in various fields.