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

SnO 2 and SnS 2 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 SnO x S 2− 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 SnO x S 2− x /GNS nanocomposites ( x = 0.3-1.3) have homogenously anchored on graphene nanosheets, which consists of a single phase (SnO 2 or SnS 2 ) 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 . A SnOS/GNS nanocomposite consisting of a single phase nanocrystal (3-5 nm) improves the kinetics of the electrochemical reactions of lithium-ion batteries.