In-Situ Synthesis of FeF₃/Graphene Composite for High-Rate Lithium Secondary Batteries

Highlights: • Nano-FeF₃/graphene composite was fabricated by an in-situ method. • The less than 5% graphene-containing composite exhibited excellent electrochemical property. • Ultrafine particle and the uniform graphene network lead to the superior lithium storage property. • Different processing conditions and different carbon sources both influence the electrochemical performance. - Abstract: Nano-FeF₃/graphene composite is successfully fabricated by an in-situ method. The structure and morphology of the samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The effect of different processing conditions and different carbon sources is investigated. The electrochemical performance of FeF₃/graphene is examined by discharge/charge and electrochemical impedance measurements. The results show that the less than 5% graphene-containing composite exhibits high capacity, stable cycling, and outstanding rate capability. The ultrafine particle size and the homogeneous network between FeF₃ and graphene both contribute to the excellent electrochemical property