Liquid phase co-exfoliated MoS2–graphene composites as anode materials for lithium ion batteries

We report a facile method to prepare the MoS2–graphene composites by liquid phase co-exfoliation of commercial MoS2 with graphene nanoplatelet (GnP) and chemically converted graphene (CCG) in N-methyl pyrrolidone with the aid of ultrasonication. The combination of SEM, XRD and BET results reveal that the MoS2–graphene composites are mesoporous materials consisting of very thin MoS2 flakes and graphene sheets. The prepared MoS2–graphene composites display good performance as anode materials for lithium ion batteries. Exfoliation of the MoS2 is the key factor for high electrochemical lithiation/delithiation performance. The MoS2/CCG composite exhibits the best reversible capacity (up to 750 mA h g−1 after 50 cycles), excellent cycling stability and high rate capability. The reversible capacity at a rate of 2000 mA g−1 is over 350 mA h g−1 and recovers to as high as 720 mA h g−1 at a rate of 100 mA g−1.

► MoS2/graphene composites were prepared by liquid phase co-exfoliation. ► Thin flakes of exfoliated MoS2 facilitate the access of Li+ during lithiation. ► MoS2/CCG shows good capacity, excellent cycling stability and high rate capacity.