A facile one–pot synthesis of Sn/graphite/graphene nanocomposites as anode materials for lithium–ion batteries

Abstract

In this report, Sn/graphite/graphene nanocomposites are successfully developed as advanced anode materials for lithium–ion batteries via a facile one–pot synthetic process. The nanocomposites are investigated by X–ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscope, transmission electron microscope, X–ray photoelectron spectroscopy, Brunauer–Emmett–Teller surface area analysis and Thermogravimetric analysis. Results suggest that Sn nanoparticles are tightly embedded in reduced graphene oxide nanosheets, which are in intimate contact with graphite, benefitting to enhance the electrochemical performance of the composites. The lithium storage properties of the samples are evaluated by cyclic voltammetry and galvanostatic charge/discharge tests. The Sn/graphite/graphene nanocomposites demonstrate improved initial coulombic efficiency. As compared to Sn/graphene, Sn/graphite, graphene, graphite and Sn, the ternary composites exhibit superior electrochemical performance. After 450 cycles, the composites remain a reversible capacity as high as 708 mAh g−1. Remarkably, electrochemical impedance spectroscopy results indicate that the combination of graphite, graphene and Sn can reduce the electrochemical reaction resistance of Sn effectively, and hence improving the electrochemical activity and the lithium storage properties of the nanocomposites.