SnOxS2-x/GNS nanocomposites for reversible and high-capacity lithium-ion batteries

SnO2 and SnS2 anode materials can improve the cycle stability of tin-based electrodes compared with Sn. However, they usually lead to huge initial irreversible capability and lower initial efficiency. To solve these problems, we reported SnOxS2-x/GNS nanocomposites with a large surface area and small particle size, which can improve the kinetics of the electrochemical reactions and realize a reversible Li+ storage process. The obtained SnOxS2-x/GNS nanocomposites (x = 0.3-1.3) have homogenously anchored on graphene nanosheets, which consists of a single phase (SnO2 or SnS2) nanocrystal (3-5 nm) and are surrounded by large amorphous areas. This unique structure makes the Li+ storage process of the obtained nanocomposites fully reversible. Specifically, the SnOS/GNS nanocomposite exhibits a good cycling performance of 1066 mA h g(-1) at 0.2 A g(-1) after 50 cycles and a rate capability of 402 mA h g(-1) at 2 A g(-1).