Synthesis of (Co/LiF/C) nanocomposite and its application as cathode in lithium-ion batteries

Abstract [Co/LiF/C] nanocomposite has been synthesized by pyrolysis of a cobaltocene/LiF mixture at 700 °C in a closed reaction vessel under argon atmosphere. The morphology, structure and composition of the material was characterized by Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen physisorption measurement (BET) and elemental analysis. The composite is comprised of hexagonally closed packed ( hcp ) and face centred cubic ( fcc ) cobalt nanoparticles and LiF, which are embedded in a matrix of graphitic nanostructures. The composite has both micro- (0.05 cm 3  g −1 ) and mesopores (0.1 cm 3  g −1 ), and exhibits a BET surface area of 177 m 2  g −1 . Electrochemical characterizations were performed versus lithium to determine the capacity, cyclic stability and to investigate the reaction mechanism. At a given current density of 27.8 mA g −1 the composite electrode exhibits an initial specific discharge capacity of 152 mAh g −1 (based on cobalt and fluorine content) which stabilizes at about 170 mAh g −1 over 70 cycles.