A rapid microwave heating route to synthesize graphene modified LiFePO4/C nanocomposite for rechargeable lithium-ion batteries

A simple and rapid method for synthesizing graphene modified LiFePO4/C nanocomposite has been developed for the first time by using a microwave heating. The obtained sample is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectra, Fourier transform infrared spectroscopy (FTIR) and various electrochemical testing techniques. XRD results indicate that the nanosized olivine LiFePO4/(C+graphene) is successfully synthesized. The size of as-synthesized nanoparticles can be controlled below 200 nm with good reproducibility through this route. TEM image shows that the LiFePO4/C nanoparticles are embedded in graphene sheets. The electrochemical performance results reveal that the modification of LiFePO4/C with graphene could construct an effective conducting network, which significantly enhance the properties of LiFePO4/C based composite, including high discharge capacity, stable cycle performance, good rate capability and small charge-transfer resistance. The excellent performance shows that the graphene modified LiFePO4/C synthesized via microwave heating is a promising cathode material for rechargeable lithium-ion batteries.