Hierarchical Sb2S3/SnS2/C heterostructure with improved performance for sodium-ion batteries

Metal sulfides are promising anode materials for sodium-ion batteries (SIBs) because of their high theoretical capacities. However, they are usually limited by their poor cycling performance and rate properties due to their large volume expansion and sluggish reaction kinetics. Herein, Sb2S3/SnS2/C heterostructures were fabricated by directly growing SnS2 nanoplates on Sb2S3 nanorods and then coating their surface with a carbon layer. Sodium-ion diffusion in several electrodes and different electrolytes was further evaluated to investigate the electrochemical performance of the heterostructures. Results revealed that the heterostructures greatly enhanced material stability and promoted ion and electron transport. Consequently, the Sb2S3/SnS2/C composites displayed a high reversible capacity of 642 mA h g−1 at a current density of 1 A g−1 after 600 cycles and a good rate performance of 367.3 mA h g−1 at 4 A g−1 in a NaPF6-diglyme electrolyte. Therefore, Sb2S3/SnS2/C heterostructures are promising anode materials for SIBs.