Encapsulating SnS2 nanosheets into hollow carbon sphere: A yolk-shell SnS2@C composite with enhanced sodium storage performance

In this study, a yolk-shell structured SnS2@C composite is rationally synthesized through a sulfuration treatment of hollow SnO2@C composite. The unique structure with SnS2 nanosheets (a thickness of 15 nm) encapsulated within hollow carbon spheres (∼400 nm) is confirmed through SEM, TEM, XRD and XPS characterizations. As an anode material for sodium-ion batteries, as-synthesized SnS2@C composite shows superior sodium storage performance. It delivers good cycling stability with a capacity of 690 mA h g−1 sustained after 100 cycles at 0.1 A g−1. Even at a high rate of 10 A g−1, an impressive rate capability of 310 mA h g−1 is still obtained. The excellent performance of this SnS2@C composite could be attributed to its unique architecture to provide good electrical conductivity, shorten the diffusion path, tolerate the volume fluctuation, prevent the aggregation, and enhance the structure stability during cycles.