Preparation of Cu2S@rGO hybrid composites as anode materials for enhanced electrochemical properties of lithium ion battery

Abstract Cu2S has attracted great attention as anode material of lithium ion battery due to high theoretical capacity and good electron conductivity. However, the poor cyclic stability due to volume change during charging and discharging restrains its further application. Herein, to improve stability of Cu2S, 3D matrix composed of reduced graphene oxide (rGO) scaffold and Cu2S nanoflowers are synthesized by hydrothermal method and freeze-drying process. The 3D matrix structure could relieve the structural and morphological variation of nanoparticles during charge and discharge processes, and rGO as bridge increases the effective area that is simultaneously accessible to electrons and lithium ions to improve the specific capacity of Cu2S nanoflowers. Thus, excellent capacity, stable cycle life and preferable rate capability could be simultaneously realized. The 3D Cu2S@rGO composite electrodes show the specific capacity of 1630 mAh g−1 for the first cycle and a reversible capacity of 600 mAh g−1 after 200 cycles at 100 mAh g−1.