Graphene oxide sheets-induced growth of nanostructured Fe3O4 for a high-performance anode material of lithium ion batteries

Nanostructured Fe3O4 is intrinsically prone to aggregation, which hinders insertion and extraction of lithium ions. To overcome this problem, we adopt graphene oxide sheets (GOS) and induce growth of nanostructured Fe3O4 on the GOS in the presence of hexamethylenetetramine (HMT). During the synthetic process, GOS provides a template to regulate the growth of nanostructured Fe3O4 and the HMT is able to coordinate with Fe3+ and control its hydrolysis rate. After the annealing process, GOS is reduced to GS (graphene sheets), and Fe3O4/GS composite is obtained. In this hierarchical structure, GS is capable of enhancing the electronic transport of Fe3O4, and the Fe3O4/GS composite has superior electronic conductivity (106 S m(-1)). Benefitting from the uniform dispersion of the nanosized Fe3O4 on GS and the superior electronic conductivity, the obtained Fe3O4/GS exhibits prolonged cycling stability (1002 mA h g(-1) after 175 cycles at a current density of 0.50 A g(-1)) and excellent rate capability (715, 647 and 535 mA h g(-1) at 1.6, 3.2 and 5.0 A g(-1), respectively).