Three-dimensional structure S-SnS2/NSG with sulfur vacancies for high-performance lithium-ion batteries

In this contribution, a new three-dimensional (3D) structure of SnS2 with sulfur vacancies (S-SnS2)anchored on the surface of reduced graphene oxide (rGO) was synthesized via a facile solvothermal method. It was found that the addition of glycolic acid promoted the bonding of SnS2 with rGO, and enabling SnS2 to generate sulfur vacancies. As a result, the obtained unique 3D structure facilitated the rapid diffusion of lithium-ion and the S/N-doped rGO (NSG) enhanced the electronic conductivity of the S-SnS2/NSG. In detail, the S-SnS2/NSG as an anode in lithium-ion battery displayed a significant capacity of 1030.2 mA h g−1 at 0.5 A g−1 after 200 cycles. Even at a large current density of 5 A g−1, the S-SnS2/NSG retained an unsurpassed capacity of 790 mA h g−1 after 1000 cycles, demonstrating an ultrastable long cycling performance.