Self-assembly of Fe3O4 nanorods on graphene for lithium ion batteries with high rate capacity and cycle stability

Fe3O4 nanorod graphene composites (FNGC) have been successfully prepared via in situ self-assembly by mild chemical reduction of graphite oxide and (NH4)2Fe(SO4)2 in water with hydrazine as reducing agent under normal pressure. Scanning electron microscopy and transmission electron microscopy observations confirmed that the as-formed Fe3O4 nanorods, about 11 nm in diameter and more than 100 nm in length, were uniformly anchored on graphene nanosheets. Electrochemical investigation showed that the FNGC exhibited improved cycling stability and superior rate capacity in comparison with Fe3O4 nanoparticles. A charge specific capacity of 867 mA h g− 1 was maintained with only 5% capacity loss after the 100th cycle at 1 C. At a current density of 5 C, its charge capacity was 569 mA h g− 1. The results suggested that FNGC is a promising candidate for practical application as lithium ion battery anode material.

Graphical abstractFe3O4 nanorod graphene composites were firstly prepared by self-assembly at airmosphere pressure in a beaker. The as-formed Fe3O4 nanorods with about 11 nm in diameter and more than 100 nm in length were uniformly anchored on graphene sheets. An electrochemical investigation shows that the FNGC exhibit improved cycling stability and superior rate capacity in comparison with that of Fe3O4 nanoparticles graphene. A charge specific capacity of 867 mA h g− 1 can be maintained and the capacity loss is only 5% after the 100th cycle at 1 C. At the current density of 5 C, its charge capacities is 569 mA h g− 1.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Fe3O4 nanorod graphene composites were firstly prepared by self-assembly. ► The Fe3O4 nanorods were uniformly anchored on graphene sheets. ► Fe3O4 nanorod graphene composites show high cycling stability and rate capacity. ► The capacity loss was only 5% after the 100th cycle at 1 C. ► At the current density of 5 C, its charge capacity was 569 mA h g− 1.