FeS2/C composite as an anode for lithium ion batteries with enhanced reversible capacity

Carbon coated FeS2 (FeS2/C) composite is prepared via a simple solid state reaction using glucose as carbon source. The porous FeS2 particles are uniformly surrounded by the amorphous carbon coating. As an anode material for lithium ion batteries, the FeS2/C composite exhibits higher reversible capacity and better cycling performance than the unmodified FeS2. The specific capacity of the FeS2/C composite after 50 cycles is 495 mAh g−1, much higher than that of FeS2 (345 mAh g−1). In order to investigate the effect of carbon coating, the cycled electrodes have been analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The improvement is attributed to the introduction of carbon coating, which can enhance the conductivity, reduce the dissolution of sulfur and corrosion from HF, and stabilize the porous structure during cycling.

► FeS2/C composite is prepared by a simple solid state reaction for the first time. ► The result of XPS shows the carbon coating can reduce the corrosion from HF. ► The result of ICP shows the carbon coating can reduce the dissolution of sulfur. ► FeS2/C composite shows superior electrochemical performance.