Sn/graphene nanocomposite with 3D architecture for enhanced reversible lithium storage in lithium ion batteries

A general strategy has been demonstrated to achieve optimum electrochemical performance by constructing 3D nanocomposite architecture with the combination of nanosize Sn particles and graphene nanosheets. In the first step, the lithium storage properties of graphene have been investigated by first principles calculations. The results show that lithium can be stably stored on both sides of graphene sheets (LiC3), inducing in a theoretical capacity of 744 mAh/g. In the second step, a synthetic approach has been designed to prepare Sn/graphene nanocomposite with 3D architecture, in which Sn nanoparticles act as a spacer to effectively separate graphene nanosheets. FESEM and TEM analysis revealed the homogeneous distribution of Sn nanoparticles (2-5 nm) in graphene nanosheet matrix. Cyclic voltammetry measurement has proved the highly reversible nature of the reaction between Li+ and Sn/graphene nanocomposite. The 3D nanoarchitecture gives the Sn/graphene nanocomposite electrode an enhanced electrochemical performance. This strategy can be extended to prepare other anode and cathode materials for advanced energy storage and conversion devices such as lithium ion batteries, supercapacitors, and fuel cells.