Towards high performance lithium storage anodes: Design strategy for carbon coated SnS–SnO2/rGO nanocomposites

The new anode materials for lithium-ion batteries (LIBs), nanocomposites of carbon-coated SnS and SnO 2 riveted on rGO sheets (denoted as C@(SnS–SnO 2 /rGO)), were constructed by effective, facile, and low-cost techniques. Benefiting from the dual-carbon modification (rGO and carbon coating layer), the C@(SnS–SnO 2 /rGO) nanocomposites exhibited significantly improved rate capability and cycle stability as compared to uncoated SnS–SnO 2 /rGO materials. At a current density of 100 mA g −1 after 300 cycles, especially, the C@(60SnS–SnO 2 /rGO) nanocomposite delivered a higher reversible capacity of ∼637 mAh g −1 as compared to the uncoated 60SnS–SnO 2 /rGO composite (∼359 mAh g −1 ). Even at a high current density of 1000 mA g −1 , the C@(60SnS–SnO 2 /rGO) nanocomposite anode still provided a high reversible capacity of ∼574 mAh g −1 after 300 cycles and the capacity continuously increased to ∼674 mAh g −1 after 500 cycles. The outstanding electrochemical performances of the new nanocomposites made them good candidates for use as high-performance anode materials. Moreover, the present research provides insights for the structural design of Sn compound-based composite electrodes which will be important for the future development of high-performance LIB anode materials. • New nanocomposites of C@( x SnS-SnO 2 )/rGO ( x = 20, 40 and 60 wt%) were prepared by facile and low-cost approaches. • Carbon layer can significantly improve the electrochemical performances of C@(SnS–SnO 2 /rGO) nanocomposites. • The highest capacity of 637 mAh g −1 at 100 mA g −1 after 300 cycles was found in the C@(60SnS–SnO 2 /rGO) nanocomposite. • At 1000 mA g −1 , the C@(60SnS–SnO 2 /rGO) anode still delivered a high capacity of 674 mAh g −1 after 500 cycles.