Syntheses of Fe3O4 and Fe3O4/Graphene Composites and Electrochemical Properties Researches as Anodes for Lithium Ion Batteries

Abstract

Fe3O4microspheres and its composities with graphene are prepared by the controlled thermal decomposition of an iron alkoxide precursor, which are obtained via an ethylene glycol (EG) mediated solvothermal reaction of ferric chloride hexahydrate (FeCl3·6H2O) and sodium acetate (NaAc) with graphene dopings. The resulting Fe3O4microspheres are uniform with a diameter of 0.2-0.5μm. Electrochemical properties of both Fe3O4microspheres and Fe3O4/graphene composites are discussed. SEM analysis shows that a large number of Fe3O4particles with spherical morphologies are homogeneously anchored to the rGO sheets surface. Electrochemical results showed that charge and discharge capacities for Fe3O4/graphene composites are larger than those for Fe3O4microspheres electrodes after the 30th cycles which due to the synergistic effect of Fe3O4and graphene. Graphene improves the electronic conductivity of Fe3O4microspheres and increases the interfacial contact area between the Fe3O4microspheres and electrolyte which is benefitable for lithium ion battery. So Fe3O4/graphene composites are better anode materials than Fe3O4microspheres.