Fe3O4 nanoparticles grown on graphene as advanced electrode materials for supercapacitors

A novel composite of magnetite (Fe 3 O 4 ) nanoparticles (NPs) grown on reduced graphene oxide (rGO) has been synthesized by a facile hydrothermal technique without any surfactants or templates. In this method, the growth of Fe 3 O 4 NPs and the reduction of graphene oxide (GO) are completed in one single step. Moreover, we have prepared Fe 3 O 4 microcubes and Fe 3 O 4 /carbon nanotubes (CNTs) composite under the same condition. The electrochemical properties of the as-prepared samples are investigated as advanced electrode materials for supercapacitors. It is found that the Fe 3 O 4 /rGO nanocomposite displays much higher specific capacitances and better cycle stability than those of pure Fe 3 O 4 and Fe 3 O 4 /CNTs composite. Specifically, it exhibits a high specific discharge capacitance of 220.1 F g −1 at 0.5 A g −1 and remains stable after 3000 charge/discharge cycles. The improvement of the electrochemical performances of Fe 3 O 4 /rGO may be attributed to the chemical interaction between rGO and Fe 3 O 4 , lower agglomeration and smaller particle size of Fe 3 O 4 .