Scalable synthesis of SnS2/S-doped graphene composites for superior Li/Na-ion batteries

Abstract

Tin disulfide (SnS₂) has emerged as a promising anode material for lithium/sodium ion batteries (LIBs/SIBs) due to its unique layered structure, outstanding electrochemical properties and low cost. However, its poor cycling life and time-consuming synthesis as well as low-yield production hinder the practical utilization of nanostructured SnS₂. In this work, we demonstrate a simple and reliable dissolution–regeneration strategy to construct a flexible SnS₂/sulfur-doped reduced graphene oxide (S-rGO) composite as anodes for LIBs and SIBs, highlighting its mass-production feature. In addition, the robust affinity between SnS₂ and S-rGO without interstitial volume is very beneficial for preventing the SnS₂ particles from breaking themselves away from the rGO nanosheets into free nanoparticles. As a result, the SnS₂/S-rGO composite as anodes delivers high reversible capacities of 1078 mA h g⁻¹ and 564 mA h g⁻¹ (at 0.1 A g⁻¹) for LIBs and SIBs, respectively, and excellent rate capabilities and cycling stability (e.g. 532 mA h g⁻¹ during the 600 cycles at 5.0 A g⁻¹ for LIBs). Our proposed strategy may also possess great potential for the practical application of other electrochemically active metal sulfide composites for energy devices.