One-step synthesis of hollow porous Fe3O4 beads–reduced graphene oxide composites with superior battery performance

We report the synthesis of a novel hollow porous Fe3O4 bead–rGO composite structure for lithium ion battery anode application via a facile solvothermal route. The formation of hollow porous Fe3O4 beads and reduction of graphene oxide (GO) into rGO were accomplished in one step by using ethylene glycol (EG) as a reducing agent. In this composite structure, the hollow porous Fe3O4 beads were either chemically attached or tightly wrapped with rGO sheets, leading to a strong synergistic effect between them. As a result, the obtained Fe3O4–rGO composite electrodes could deliver a reversible capacity of 1039 mA h g−1 after 170 cycles between 3 V and 50 mV at a current density of 100 mA g−1, with an increment of 30% compared to their initial reversible capacity, demonstrating their superior cycling stability.