Self-assembly of Fe2O3 nanotubes on graphene as an anode material for lithium ion batteries

Fe2O3@rGO composite has been successfully prepared by a simple hydrothermal method with the assistance of polyvinylprrolidone (PVP). Under the dispersion of PVP, alpha-Fe2O3 nanotubes are well anchored on the surface of wrinkled graphene nanosheets, forming quasi-laminated-like architecture. Owing to the synergic effects between alpha-Fe2O3 hollow nanotubes and graphene, Fe2O3@rGO composite exhibits superior electrochemical properties as an anode material for lithium ion batteries with high reversible capacity and good rate capability. The initial discharge-charge capacities of Fe2O3@rGO composite can reach 1681 and 1367 mAhg(-1) at a current density of 50 mAg(-1), respectively. Even after 100 cycles, the capacity can be retained as high as 656 mAhg(-1) at a current density of 100 mAg(-1), much beyond than that of bare alpha-Fe2O3 nanotubes and Fe2O3/graphene reported previously. Meanwhile, it is found that graphene oxides can be reduced to reduced graphene oxides during the hydrothermal treatment. The critical role of graphene to the electrochemical performance of composite has also been elucidated in this paper. (C) 2018 Elsevier B.V. All rights reserved.