Scalable synthesis of Fe₃O₄ nanoparticles anchored on graphene as a high-performance anode for lithium ion batteries

We report a scalable strategy to synthesize Fe₃O ₄/graphene nanocomposites as a high-performance anode material for lithium ion batteries. In this study, ferric citrate is used as precursor to prepare Fe₃O₄ nanoparticles without introducing additional reducing agent; furthermore and show that such Fe₃O₄ nanoparticles can be anchored on graphene sheets which attributed to multifunctional group effect of citrate. Electrochemical characterization of the Fe₃O₄/graphene nanocomposites exhibit large reversible capacity (∼1347 mA h g^-1 at a current density of 0.2 C up to 100 cycles, and subsequent capacity of ∼619 mA h g^-1 at a current density of 2 C up to 200 cycles), as well as high coulombic efficiency (∼97%), excellent rate capability, and good cyclic stability. High resolution transmission electron microscopy confirms that Fe₃O ₄ nanoparticles, with a size of ∼4-16 nm are densely anchored on thin graphene sheets, resulting in large synergetic effects between Fe ₃O₄ nanoparticles and graphene sheets with high electrochemical performance.